國立交通大學電子物理研究所碩士論文N germanium photodiodes. To investigate the main physical mechanism behind the dark current of germanium photodiode, analysis of

指導教授趙天生博士

研究生吳立盈

中華民國一百零一年九月

國立交通大學

電子物理研究所

碩士論文

鍺基紅外光偵測器應用於光連接系統之

設計與建模

Design and modeling of Germanium based Photodetectors for

on-chip optical interconnects

ii

iii


設計與建模

Design and modeling of Germanium based Photodetectors for on-chip optical interconnects

國立交通大學

電子物理所碩士班

碩士論文

Institute of Electrophysics

National Chiao Tung University

A Thesis Submitted to Department of Electronphysics College of

Science National Chiao Tung University in Partial Fulfillment of the

Requirements for the Degree of Master of Science in Electrophysics

September 2012

Hsinchu Taiwan Republic of China


指導教授趙天生博士 Advisor Dr Tien-Sheng Chao

研究生吳立盈 Student Li-Ying Wu

iv

v

AbstractAs one of the crucial components in optical interconnect system germanium photodiodes(GePD)arepromisingduetoitscorrespondingbandgap(066eV)toabsorbinfra‐redlightandthecompatibilitytosilicon‐basedphotonicsandelectronicsHowevermanyresearchershaveshownthatthekeyissueofGePDishighdarkcurrentandeffortsweredonetosuppressthedarkcurrentandtoincreasegain‐bandwidthproductbyimprovingGePDefficiencyandspeedThisthesisaimstosystematicallyfindthephoto‐electricalbehaviorbasedonthesimplestP‐i‐N germanium photodiodes To investigate the main physical mechanism behind the darkcurrent of germanium photodiode analysis of temperature dependence ofexperimentallymeasureddarkcurrentisperformedAfterthatseveralguidelinestowardtheGePDstructureareprovided in this thesiswith theaidofTCADsimulationwhich canbeauseful referencewhenfabricatinghigh‐efficiencyandlow‐powerconsumptiongermaniumphotodetectorwithlateralP‐i‐Nstructure

vi

vii

摘要

在取代積體電路銅導線的光連接傳輸系統中紅外光偵測器是光學訊號接收端的重要

元件其中鍺的能隙(066 eV) 使得鍺基元件能夠有效吸收紅外光訊號鍺基紅外

光偵測器近年來成為許多研究的題目文獻指出鍺基紅外光偵測器的主要缺點是暗

電流過高造成訊號干擾以及額外功率消耗本篇論文以水平 P-i-N 結構的鍺基紅外

光偵測器為研究對象首先透過變溫量測與分析得知在室溫以及小偏壓操作下暗

電流來自於 Shockley-Read-Hall 載子產生過程 (SRH generation)接著利用 TCAD 模

擬軟體取用上述 SRH 模型模擬不同幾何參數對於偵測器之暗電流光電流以及傳

輸速度的影響探討各參數的權衡與最佳化為未來提供製造低雜訊高效率以及高

頻寬的鍺基紅外光偵測器的方針

viii

ix

Foreword IrsquodliketoacknowledgethecontributionoftwopersonstothisthesisOneisProfMarcHeynsthe thesis supervisor whose advisement enables this thesis more physically logical One is Dr Geert Hellings my daily supervisor I deeply appreciate him for his generous teaching continued guidance and endless patience I am also grateful to members in KULeuven University and National Chiao‐Tung Universitywhoare in chargeof thedual‐degreeMasterprogramwhichprovidedme suchawonderfulopportunitytostudyhereFor the two‐yearresearchdays inTaiwan Irsquod like toacknowledgeProfTien‐ShengChaowhoisnotonlyanencouragingteacherbutalsoasupportingmentorInthefreeandrespectfulresearchenvironmentheprovidesIamluckytomeetallthemembersin theAdvancedSemiconductorDeviceFabrication andMeasurementLab and the timeswespenttogetherstudyinganddoingexperimentsinthecleanroomaredefinitelymemorableFinallyabig thankyougoes tomydear familywherever inTaiwanorBelgium Inever stopfeelingtheirimmediateloveandsupport

Li‐YingWu

x

xi

TableofContentsAbstract v

摘要 vii

Foreword ix

TableofContents xi

Listoffiguresandtables xiii

Listoffigures xiii

ListofTables xv

Chapter1 Introduction 1

11OpticalInterconnectASystemOverview 1

111History 1

112Photodiodesinopticalinterconnectsystem 2

12WorkingprincipleofP‐i‐NGePD 3

Chapter2 ExperimentalInvestigationofDarkCurrentinGermaniumphotodiodes 5

21DarkCurrentMechanismsinGePhotodiode 5

211DiffusionCurrents 5

212SRHcurrent 7

213TunnelingandImpactIonization 9

22MeasurementsofGermaniumphotodiodes 10

221StructureofGePD 10

222Temperaturedependencemeasurement 11

23TemperatureDependenceofdarkcurrent 13

24Conclusion 19

Chapter3 DarkCurrentinGermaniumphotodiodesTCADsimulation 21

31TCADModels 21

311DefaultModelsinTCAD(includingDiffusion) 21

312SRHTheShockley‐Read‐HallModel 21

32BasestructureformedinTCAD 22

xii

33TCADOptimizationofDarkCurrent 26

331Alterationsinthickness 26

332Alterationsinwidth 29

333Alterationsinimplantenergy 32

34Conclusion 33

Chapter4 QuantumEfficiencyOptimization 35

41OpticalGenerationanddefinitionofQuantumEfficiency 35

411OpticalGenerationMethod 35

412DefinitionofQuantumEfficiency(QE) 37

42QEinrespectofStructuralparameters 38

421QEdependenceonthicknessandwidthofGePD 38

422QEdependenceondopingseparation 40

43QEimprovementbyJunctionengineering 42

44Conclusion 44

Chapter5 TransientResponseOptimization 45

51TheRoleofTransientResponse 45

52Speedinrespectofstructuralparameters 47

53Lengtheffect 50

531Capacitanceinlengthdirection 50

532Absorptioninlengthdirection 51

54Frequencyresponse 53

541Bitstreaminput 53

542Eyediagram 53

55Conclusion 55

Chapter6 Conclusion 57

Appendices 61

AppendixACommandcodesinTCADsimulator 63

Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70

Sdevicefortransient 72

Bibliography 75

xiii

Listoffiguresandtables

Listoffigures

Fig1‐1Systemoverviewofopticalinterconnection[4]2

Fig1‐2IllustrationandbanddiagramofalateralPiNGePDinreversebias3

Fig2‐1Energybanddiagramofp‐njunctioninreversebias6

Fig2‐2Shockley‐Read‐Hallgenerationprocess[9]7

Fig2‐3Banddiagramandtunnelingprocessofheavilydopeddiodes[9][15]9

Fig2‐4Structureofgermaniumphotodiode10

Fig2‐5LargedistributionofdarkcurrentvsLengthofGePD12

Fig2‐6TemperaturedependenceofI‐Vcharacteristics(withparasiticleakage)12

Fig2‐7TemperaturedependenceofI‐Vcharacteristics13

Fig2‐8Activationenergyversusreversebiasfromexperimentaldata14

Fig2‐9ReverseCurrents(Amicrom)versus1000T(K‐1)16

Fig2‐10Totalreversecurrentsubtractedbydiffusioncurrent17

Fig2‐11Variationofrecombinationlifetimeversuseffectivedopantconcentration[18]18

Fig3‐1SimulatedstructureofgermaniumphotodiodeinTCADshowingdopantprofilesmeshing22

Fig3‐2Simulatedstructurewithexponential(top)andconstant(bottom)defectdistributionprofile23

Fig3‐3DarkcurrentexperimentdataandresultsofExponentialdefectprofile(Top)simulationandconstantdefectprofile(bottom)simulation24

Fig3‐4Defectdeterminedforwardswingbehaviorindicatedaccuracyofthedefectdensitylevelacquiredfromsimulationofdarkcurrent25

xiv

Fig3‐5SimulateddarkcurrentasafunctionofTotalGethickness27

Fig3‐6Trapnumbercomparisonbetweenconstantandexponentialdefects28

Fig3‐7Effectsofthewidthofgermaniumondarkcurrent29

Fig3‐8Darkcurrentofdifferentdiodesversusdopingseparationratio30

Fig3‐9Electricfielddistributionindiodeswithdifferentdopingseparation31

Fig3‐10Darkcurrentversusimplantenergyratio32

Fig3‐11Electricfielddistributionofdiodeswithdifferentjunctiondepth32

Fig4‐1The2Dsingle‐modeinfraredlightintensitydistributioninsidea2DGermaniumstructureof2‐μm‐wideand02‐μm‐thick35

Fig4‐2Two‐dimGaussianopticalsignalintheTCADsimulator36

Fig4‐3 Lightdistributioninphotodiodeswithdifferentwidthandthickness38

Fig4‐4EffectsofGethicknessandwidthonQE39

Fig4‐5QEdependenceondopingseparation41

Fig4‐6DarkcurrentandQEasafunctionofimplantenergy42

Fig4‐7Deepjunctionsandshallowjunctions43

Fig4‐8Effectsofdeep‐and‐shallowjunctionsondarkcurrentandQE43

Fig4‐9TheoptimumstructureforlowdarkcurrentandhighQE44

Fig5‐1Illustrationofrisetimedefinition45

Fig5‐2EffectivecircuitofaPINphotodiode[20][21]46

Fig5‐3C‐Vcharacteristicsofsimulatedphotodiodewithvariousstructures48

Fig5‐4SpeedofGePDisinverselyproportionaltowGe48

Fig5‐5SpeedevaluationofGePDswithdifferentWiandwGe49

Fig5‐6ParasiticCapacitanceCPDobtainedwithlengthofGePD50

Fig5‐7OpticalabsorptioncoefficientofSiGeandSiGealloys[22]51

Fig5‐8Absorptionratioversuslengthofgermaniumphotodiode52

Fig5‐9Thebitstreaminputcontainscombinationsthreebits53

Fig5‐10EyediagramoftheGePDwithspeed30GHz54

xv

ListofTables

Table2‐1StructuralparametersofGePD11

Table6‐1SeveralGuidelinesfordesigningGePD59

Table6‐2GePDequivalentcircuit[19][20]andacquiredvalueofcomponents60

xvi

1

Chapter1 IntroductionThe objective of this thesis is to find an optimum structure of the germaniumphotodiode inside the optical interconnect system To start a system overview ofopticalinterconnectisintroducedandtheworkingprincipalofaphotodiodeisgiven

11OpticalInterconnectASystemOverview

111History

Informationprocessingreliesonlinearandnon‐lineardevicesandcircuitsforlogicand storage functions and also requires interconnections to carry the signal fromoneplace toanotherAs thecountingreduction in featuresizesonelectronicchipsleads to a larger numbers of faster devices at lower cost per device the scaling ofelectricalinterconnectionsdoesnrsquotkeepupwiththegrowthofelectricaldevicesThetraffic in long‐distance is limited by various problems of electrical wiring forexamplehighresistanceandhighparasiticcapacitanceoflongwiresThisdegradesthespeedimprovementviadevicesresearchesandglobalinterconnectswillbecomeverydifficultifpeoplekeepusingconventionalmethod[1]Theresearchforopticalinterconnectsstartingasearlyassemiconductordiodelaserhad been invented and the first idea that optical interconnects can be utilized invery‐largescale‐integration(VLSI)wasproposedandanalyzedbyGoodmanetalin1984 Same year the quantum confined Stark effect was discovered in III‐Vsemiconductor quantum wells which enables efficient high‐speed opticalmodulatorsIntegratedwaveguideversionsofsuchmodulatorsareextensivelytodayforhigh‐performanceapplications[2]Theadvantagesofusingopticalinterconnectsmakesdevelopmentattractivesuchasless distancedependency onperformance ability to have 2‐D interconnects ratherthan connect from edge and feasibility of wavelength division multiplexedinterconnectswithoutusinganyelectricalmultiplexingcircuitryMoredetailswereenumeratedinliteratures[1][3]

2

112Photodiodesinopticalinterconnectsystem

OpticalinterconnectsrequiretheintegrationofvarioustechnologiesFig1‐1showsthe overview of a simple set of photonic transceiver and receiver [4] whereelectrical‐optical signal transition happens Left‐hand side of Fig 1‐1 is a siliconmodulatorconsistsofopticalringresonatorsThemodulatortakeselectricalsignalsand monochromic laser lights as inputs and generates optical signals of infraredfrequencyasopticaldatawhich thenpassages througha siliconwaveguide routedon the chip and arrives at the destination chip At right‐hand side a germaniumphotodetectoristheretocapturetransmittedopticaldataandthentransferopticalsignalsintopulsesofelectricalcurrents

Fig 1‐1 System overview of optical interconnection[4]

As one of the crucial components in optical interconnect system germaniumphotodetectorsorGermaniumphotodiodes(GePDs)havebeenbroadlyinvestigatedduetoitscorrespondingbandgaptoabsorbinfraredlightat155‐μmwavelengthandthe compatibility to silicon‐based photonics and electronics GePDs monolithicallyintegrated with silicon transistor technology is viewed as the essential part ofinfraredopticalinterconnectssystemHowevermany researchershave shown that the issue technology issueofGePD ishigh dark current due to the 42mismatch betweenGe and Si and effortsweredonetosuppressthedarkcurrentbymeansofimprovingfabricationprocess[5][6]ToimproveGePDefficiencyandspeedadvancedGePDaredevelopedtoincreasethephotocurrent in regular P‐i‐N GePD by utilizing multiplication of carriers forexample Avalanche photodetector (APD) and separate‐absorption‐charge‐multiplication(SACM)photodiode[7]Literature[8]proposedthatcreationofnon‐uniformelectric field ingermaniumAPDviananoelectricengineering increasesthegain‐bandwidthproductThe purpose of this thesis is to systematically find the photo‐electrical behaviorbased on the simplest P‐i‐N germanium photodiodes but with various structuralparameterswiththeaidofTCADsimulatorsothatabasicguidelinecanbeprovidedfor the future advanced researches In next section working principles of P‐i‐Ngermaniumphotodiodeisintroduced

3

12WorkingprincipleofP‐i‐NGePD

Fig 1‐2 shows the illustration and the band diagram of a lateral P‐i‐N GePD inreverse bias Green lines represent the conduction and valence band edge atequilibrium and distance between ‐Xp0 and Xn0 represent the depletion width atequilibriumWhenareversebiasisapplieddepletionretrievesawayfromthecenterofdiode (tondashXrsquop0 andXrsquon0) and theexposed ionizeddopantsprovideextra electricfieldswhichcanbeseenfromtheincreasingslopeofbandedgesWhenphotodiode isunderphoton illuminationphotonswithsufficientenergyandcorrect momentum can excite valence electrons hence extra free electrons andcorrespondingfreeholesaregeneratedAt intrinsicregionthesephoton‐generatedexcesscarriersaredriftedbytheelectricfieldarousedbyreversebiasElectronsaredriven tonsideandholesdriven topsideCurrentgenerated fromthisprocess iscalledphotocurrentThepromptphotocurrentgeneratedinthespacechargeregionisofthemaininterestthereforedepletionregionwidthcanbemadelargetohaveaphotodiodewithhighsensitivityThatrsquosthereasonP‐i‐Nphotodiodeisused[9]The current appeared without illumination is called dark current which isundesirablesinceitwouldraisetheconsumptionofpowerMechanismsbehinddarkcurrentaregiveninnextchapter

Fig 1‐2Illustration and band diagram of a lateral PiN GePD in reverse bias

Inthefollowingchaptersoperationconditionsareallconsideredunderareversebiasofabsolutevalue05voltandforshortsometimesitisputas‐05V

4

5

Chapter2 Experimental

InvestigationofDarkCurrentin

GermaniumphotodiodesIn this chapter dark currents mechanisms are enumerated Next the results oftemperaturedependencemeasurementofGePDdark currents and theanalysis arepresented

21DarkCurrentMechanismsinGePhotodiode

To start with several components of photodiode dark current which result fromdifferentmechanismsareconsideredbeforeanalysisTheyarerespectivelydiffusioncurrent thermal generation current tunneling current and impact ionizationcurrent[10]Awell‐performed photodiode needs to keep its dark current low enough to avoidhighpowerconsumptionatstand‐bystageandevennoisewhenlightsignalsturnedonComparedtosilicondevicesgermaniumdiodeismorelikelytobesufferedfromhigherjunctionleakageduetoitssmallbandgap(066eV)Whatrsquosmorehighdarkcurrent leakage is the critical issue in Ge PDs technology as compared with III‐Vbasedphotodiodes Therefore clarifying of themain recombinationmechanisms isindispensableforofGephotodiodeelectricalbehaviorsimulationandfurtherforGephotodiode optimization In this chapter the physical mechanisms behind darkcurrentareviewedandtheexperimentalinvestigationofdarkcurrentisperformed

211DiffusionCurrents

Diffusion current is proportional to the gradient of the carrier concentrationevaluatedattheinterfacebetweenthedepletionandtheneutralregion[11]Energybanddiagramofap‐njunctioninreversebiasisshownasFig2‐1Forexampleinp‐typequasi‐neutral regionareas theequilibriumminorityorelectronconcentrationnp0is

Eq 2‐1

whereNA isacceptorconcentration inp‐typeregionThoseelectronswoulddiffuseton‐typeregioniftheyareclosetospace‐chargeregionhence

6

1 Eq 2‐2

Eq 2‐3

SinceniispositivelycorrelatedtotemperaturewecantellfromEq2‐3thatdiffusioncurrentwouldincreaseswhenrisingtemperaturewithanactivationenergyequalstothebandgapofgermanium[12]

Fig 2‐1 Energy band diagram of p‐n junction in reverse bias

7

212SRHcurrent

Besides diffusion current recombination‐generation current should also beconcerned Since basically photodiode operates in ‐05 volts under this reverseconditiontheelectricfieldindepletionregionsweepsholestothep‐typeregionandelectrons to n‐type region Because of the reduction in carrier concentration (np laquoni2)systemispronetogeneratemorecarrierstomeetequilibriumMany researchers have found dark current is greatly depends on the quality ofjunction layers This indicates that the generation process involves impurities orimperfections Those imperfections disrupt the lattice of semiconductor andintroduce energy levels into the band‐gap In our case most of the imperfectionscome fromdislocations at the interface of siliconwaveguide and germanium layerdue to lattice mismatch Fig 2‐2illustrates this generation process or so‐calledShockley‐Read‐Hallrecombination

Fig 2‐2 Shockley‐Read‐Hall generation process[9]

The net generation‐recombination rate U of carriers through these intermediatecentershasbeensuccessfullydescribedbyHallShockleyandbyRead[13][14]Itcanbeshownthat

Uσ σ v pn n N

σ n n exp σ p n exp Eq2‐4

whereσpandσnarethecapturecross‐sections forholesandelectronsrespectivelyvthisthethermalvelocitynistheelectronconcentrationpistheholeconcentrationNtistheconcentrationofbulkgeneration‐recombinationcentersattheenergylevelEtEiistheintrinsicFermilevelandnitheintrinsiccarrierconcentration

8

To summarize components of diffusion and thermal generation currents in a p‐njunctioncouldbedescribedasfollowingequation[Szesensor]

∙ Eq2‐5

whereqiselementarychargeDnistheelectrondiffusivityτnistheelectronlifetimeNA is the doping level of the p‐type region ni is the intrinsic concentration ofsemiconductor inthiscasegermaniumτgen isthegenerationlifetimeandWisthedepletionwidthAsimilarexpressionholdsforholesThe second term of Eq 2‐5 states SRH recombinationgeneration current isdependentoncarrierlifetimeτgennamelythissourceofdarkcurrentisinfluencedbythenumberofdefectsthatservedasrecombinationgenerationsites[12]More details will be discussed in section 23 while analysis of germanium darkcurrent under different temperature and reverse bias based on experimentalmeasurementispresented

9

213TunnelingandImpactIonization

In a diode with degenerately doped p‐n junctions tunneling can be determiningwhenreversebiasisaboveacertainvaluesincedepletionregionisrelativelynarrowinhighlydopeddiodesandhencesmallertunnelingbarrierTheprocessisshowninFig 2‐3 Tunneling current could be band‐to‐band tunneling (BTBT) and trap‐assistedtunneling(TAT)

Fig 2‐3 Band diagram and tunneling process of heavily doped diodes[9][15]

At higher applied voltages impact ionization plays a role followed by avalanchebreakdownTheavalanchebreakdownprocessoccurswhencarriersmovingacrossthe space charge region acquire sufficient energy from the electric field to createelectron‐holepairsbycollidingwithatomicelectronswithinthedepletionregion[9]Analytical model describing reverse characteristics of a p‐n diode includingtunnelingcurrentandavalanchebreakdownwaspresentedin[16]HoweverinthisthesisthestructurewediscussedisaP‐i‐Njunctionwhoseintrinsicwidth is at least 05 microm With this sufficient large tunneling barrier and theoperation condition that only under low electric field itrsquos reasonable to concludethattunnelingcurrentandimpactionizationcurrentsarenegligible

10

22MeasurementsofGermaniumphotodiodes

221StructureofGePD

ThestructureGePDdeviceusedinthisthesislookslikeFig2‐4inFig2‐4(bottom)silicon layer serves as an optical signal waveguide it is recessed into trapezoidalshape by etch‐back process and from Fig 2‐4(right) we can see this trapezoidalshape is formed the (111) (113) and (100) facets of silicon The taper angle (see(bottom))isapproximately30degwhichisusedtoincreasethecouplingefficiencyforlighttotransmitthroughSiGeinterface[17]LyingontopofthesiliconisthemainbodyofphotodetectorformedbygermaniumselectiveepitaxialgrowthAfterannealingandCMPprocessboronandphosphorusimplantationisappliedtoformP+andN+siderespectivelyandaftertheprocessofoxide layerdepositionandcontact‐hole formation tungstenelectrodesare filled inThe cross‐section of GePD resembles a mushroom and the ldquocaprdquo of mushroom iscalledoverlapregionOverlapregionisdesignedtoseparatetungstenelectrodesfaraway from light intensity so that light intensity loss frommetal absorption canbedecreasedAllthemeaningsofstructuralparametersarelistedinTable2‐1

Fig 2‐4 Structure of germanium photodiode (left)Top view of GePD (right)TEM structure of GePD (bottom) GePD Structure illustration with parameters

11

Terms MeaningshGe TotalthicknessofGermaniumdiode(=hov+hBody+hRec)hBody ThicknessofGermaniumbodyhov Thicknessofoverlap

hRec Recessiondepth(=Sietched‐backthickness)wGe WidthofGermaniumdiodeWi DopingseparationWidthofintrinsicregionθ Taperedangleformedwhensiliconetch‐backprocesstSi Thicknessofsilicon

Table 2‐1 StructuralparametersofGePD

222Temperaturedependencemeasurement

To analyze dark current behavior a series measurement of the current‐voltagecharacteristic with varying temperature has been done The temperaturedependence measurement is performed by HP4156 Semiconductor ParameterAnalyzer Fig 2‐6shows the I‐V characteristics of photodiode measured underdifferent temperature from‐10degC to125degCsweepinganode(connect toP+terminalofGePD)voltagefrom‐2Vto1VHoweverinFig2‐6setsofcurvesismergingtogetherasarrowedwhichmeansthatdark currents are interfered by exterior leakage path for example leakages thatcomealongtheedgeofgermaniumFurthermorethisparasiticcurrentisdifficulttobenormalizedwith lengthbecauseaswemeasured the leakage currentsofdiodeswith1020and50μmlongandthereisnocorrelationbetweencurrentandlengthAlargedistributionisshowninFig2‐5ThisphenomenonisalsodiversefromsampletosamplethroughoutthewholewaferIt is more meaningful to analyze the intrinsic behavior of leakage currents ingermaniumphotodiode after a seriesof ldquosearching for thebestdierdquomeasurementdatathatworthydiscussingisputinthe23section

12

Fig 2‐5 Large distribution of dark current vs Length of GePD Large distribution prevents accurate extract of dark current

Fig 2‐6 Temperature dependence of I‐V characteristics (with parasitic leakage)

13

23TemperatureDependenceofdarkcurrent

TheresultofmeasuringldquothebestdierdquoisshowninFig2‐7inwhichcurvesaremoresmooth compared to those interfered by parasitic leakages And then activationenergy is estimated based on Arrhenius equation (Eq 2‐6) by fitting data withexponentialfunctionintheplottingofmeasureddarkcurrentatagivenreversebiasversus1T(not shown)andextracting theexponent tocalculateactivationenergyEaateachreversebiaspoint

Fig 2‐7 Temperature dependence of I‐V characteristics

Activation energy is the energy needed for electrons to overcome process barrierTheactivationenergy fordiffusionprocess is germaniumbandgap066eV and forSRHprocesswithdeeptrapsEashouldbeclosetohalfbandgap033eVActivationenergyversusreversebiasisshowninFig2‐8

k Ae Eq2‐6

14

Fig 2‐8 Activation energy versus reverse bias from experimental data

Dark current is initially dominated by diffusion mechanism near zero volts and continually Shockley‐Read‐Hall generation takes place in higher reverse bias

Ea of five samples as a function of reverse bias are shown in Fig 2‐8Only the topcurve (red solid triangles) maintains above Ge half bandgap (033 eV) until ‐2Vwhich is regarded behaving as intrinsic semiconductor leakage Other four curves(smalldots)reveal that thesesamplesaremoreaffectedby leakages fromparasiticconductingpathActivation energy is dropping as reverse bias increases (goes to negativeleftdirectionasarrowed)ForthetopcurveitstartswithEaasymp06eVwhichmeansthattheaveragedarkcurrentover‐10degCto125degCisdominatedbydiffusionofminoritycarriersinsmallbiasAsreversebiasgetshigherEagraduallydropscloseto03eVwhichmeans that at higher reversebias averagedark current is subjected to SRHrecombinationprocessAnother analysis shows this trend similarly In Fig 2‐9 the logarithm of themeasured leakage current (curves with blue solid symbols) at different appliedvoltagesareplottedversus1000Ttogetherwithniandnisup2dependencies(straightlineswithopensymbols)TheinsetofFig2‐9isagainEq2‐5withfirsttermrelatedtodiffusioncurrentandsecondtermrelatedtoSRHgenerationcurrentasindicatednidependencyontemperatureisshownmoreclearlyinEq2‐7Bandgapcorrectionwith respect to temperature is taken into account when plotting of ni and nisup2dependencies

222 lowast

22 lowast

2 Eq2‐7

15

In Fig 2‐9 it shows that SRH generation leakage has a stronger dependence onreversebiascomparedtodiffusioncurrentItisbecausewithhigherreversebiasthediode ismoredepleted (depletion regiongetswider)whichmeansmore trapsareexposedoutasgenerationsitesresultinginhighergenerationcurrentSetsofcurvesshowa trend that dark current ofmeasuredGePD is in a combinationbehavior ofdiffusion and SRH generation Judged from the slope and tangent line SRHgenerationisthemaincomponentindarkcurrentatroomtemperature25degCwhiletheGePDisatitsoperationpoint‐05VAbove87degCdiffusioncurrentplaysaroleFig 2‐10demonstrates this more clearly which is the zoom in version of Fig 2‐9whileY‐axisisreplacedastheamountofmeasuredcurrentsubtractedbycalculateddiffusioncurrent(firsttermofEq2‐5)whichshouldgiveSRHgenerationbehaviorA neat fittingwith SRH equation lines (five parallel yellow lines) could be seen intemperature below 25degC Deviations in higher temperature and higher reversevoltageregimearesupposedtoattributetoextracurrentfromdiodeedgewhichisrandomlydistributedasshownbefore

16

Fig 2‐9 Reverse Currents (Amicrom) versus 1000T(K‐1)

Measured current (solid symbols) at different temperature as a function of 1000T Two straight lines with open symbols are plotted from Eq 2‐5 as in the inset with first term related to diffusion current and second term related to SRH generation current as indicated

17

Fig 2‐10 Total reverse current subtracted by diffusion current

Solid symbols are measured total current subtracted by pure calibrated diffusion current from Eq2‐5 and empty symbols are pure calibrated Shockley‐Read‐Hall current from equation

Lifetimes of electrons are also roughly calculated to be 006 micros Based onliterature[18]thedefectdensityofthebestdieisestimatedaround1e19cm3fromFig2‐11InChapter3defectdensitywouldbeestimatedbyTCADsimulator

18

Fig 2‐11 Variation of recombination lifetime versus effective dopant concentration[18]

19

24Conclusion

At the beginning of this chapterwe overviewedphysicalmechanisms behind darkcurrent in a germanium photodiode Section 22 describes the structure ofgermanium photodiode used in this thesis and the temperature dependencemeasurementmethodSevereparasitic leakagewasobservedonmanydevicesDueto this yield issue a meaningful analysis could only be performed onwell‐chosendevicesSubsequentlyinsection23weshowtheinvestigationofdarkcurrentingermaniumphotodiodeviaexperimentaldataFirstly from the analysis of activation energy when the bias is small the averagedarkcurrentover‐10degCto125degCisdiffusioncurrentasbiasgetsmorereversed itwouldsubjecttoSRHprocessSecondlyitcanbeverifiedthatdarkcurrentisinthecombination behavior of diffusion current and SRH generation current At roomtemperature and at thebias ‐05V SRHgeneration is themain component in darkcurrentThereisagoodqualitativeagreementbetweenformulatrendandmeasureddataThirdly froma roughestimateof carrier lifetime equivalent trapdensitiesofourbestsamplesareestimatedtobearound1E19cm3ThiswillbemorepreciselyestimatedinChap3

20

21

Chapter3 DarkCurrentin

GermaniumphotodiodesTCAD

simulationInthepreviouschapterweconcludedthatdiffusionandSRHgenerationcurrentaremainly the leakage sources of germanium photodiode In this chapter TCADsimulationisinvolvedThischapterstartswithanoverviewofmodelsthatareusedin our simulation and the base structure we build in TCAD finally we makealteration in thebasestructureandshowanoptimumstructure thathasminimumdarkcurrent

31TCADModels

311DefaultModelsinTCAD(includingDiffusion)

Physical models used to simulate germanium photodiode are presented Diffusioncurrent can be treated as the intrinsic behavior of semiconductor It is standardlyactivatedintheTCADsimulator

312SRHTheShockley‐Read‐HallModel

AsmentionedinChapter2SRHmodeldescribesrecombinationgenerationthroughdeep‐level defects in the semiconductor bandgap The position of the dominatingtrap level in the bandgap is assumed atmidgap energy level (033 eV) for Ge[19]BasicallyanexpressionofSRHisusedintermsofminoritycarrierlifetimes(τnandτp)dependentonthelocaldefectconcentration

22

32BasestructureformedinTCAD

Theultimatepurposeof this thesis is to findanoptimizedstructureofgermaniumphotodiode through simulation so it is important to get a base structurewhich isclosetothemeasureddiodeincludingsimilargeometryandeffectivedefectdensityand thenwecanutilize thisbasestructure tosimulate thecurrentsofphotodiodeswith alteration The inclusion of TCAD enables us to get the approximate form ofdefectdensityinthemeasuredsamplesTo form a base structure the fabrication flow which is identical to experimentalsamples is simulated via TCAD sprocess tool and the final simulated structure isshowninFig3‐1ContactsaresimulatedasidealohmiccontactandinFig3‐1theyare shown in boundary only Note that simulations are done in a two‐dimensionalGePDsothecurrentfromelectricalcharacteristicsimulationisgivenbyAmperepermicrom (Amicrom) That is in simulation the length of germanium (LGe) is alwaysconsideredas1micromonlyinSection52wewouldalterLGetoseetheeffectshappeninlengthdirection

Fig 3‐1 Simulated structure of germanium photodiode in TCAD showing dopant profiles meshing

In order to estimate the defect density inside germanium photodiodes a constantdefect distribution is introduced into simulator That is we build up a simulatedgermaniumphotodiode inwhichdefects areuniformlydistributed Subsequently adefect concentration is chosen to achievea goodagreementwithmeasurementsofthedarkreversecurrentOn the other hand since dislocations aremostly generated at SiGe interface andtendtoannihilateastheepitaxialfilmthickens[5]wealsointroduceanexponentialdefect profile into another branch of simulation by assuming that defectconcentrationisspatiallypeakedatthehetero‐interfaceandexponentiallydecayedasretreatawayfromtheinterface

23

Fig 3‐2 shows the simulation structure of GePD with defects distributed inexponentialprofileandconstantprofileExperimentaldataisalsonormalizedtothelengthofGePDtomakeitcomparablewithelectricalstimulationFig 3‐3shows that simulation (black line) result fits nicelywith experimental data(redopen symbols) for themostpart of reversebias rangeThedensitywhich fitsbestwithmeasurement data is equal to 5e18cm3 for constant defect profile and1e20cm3forexponentialdefectpeakvalue

Fig 3‐2 Simulated structure with exponential (top) and constant (bottom) defect

distribution profile

Exponential Defect profile

24

Fig 3‐3 Dark current experiment data and results of Exponential defect profile (Top) simulation and constant defect profile (bottom) simulation

25

Furthermore consistencynotonlyshowsup in thereverseregion it alsoshows intheforwardbiasregionbyexaminingforwardswingAsplitofdiodeswithdifferentdefectdensityhasbeensimulatedandtheirforwardswingbehaviorisshowninFig3‐4 Swingof experimental data is also calculated frommeasured I‐V curves (solidsymbols)anditcouldbeseenthatexperimentaldataandsimulationresultsareonthe same level at the defect density corresponding to the one we obtained fromreverse dark current simulation 5e18 cm‐3 Consistency shows up in two sets ofsamplesThismeansdefectdensityacquiredfromsimulationisquitereliable

Fig 3‐4 Defect determined forward swing behavior indicated accuracy of the defect density level acquired from simulation of dark current

TosummarizedwehaveestimatedthedefectdensityofgermaniumphotodiodeviaTCADsimulationtoolForconstantdefectprofileassumptiondefectsareuniformlydistributedwith5e18cm3concentrationForexponentialdefectprofileassumptiondefectshaveapeakvalue1e20cm3attheinterfaceofSiGeandexponentiallydecaytowardstopsurfaceTheresult is foundreliablebecausethefittingofsimulatedvalueandexperimentaldataarewell indarkcurrentandforwardswingThefollowingsectionwewillseethesimulationsbasedonthesetwostructures

26

33TCADOptimizationofDarkCurrent

331Alterationsinthickness

This section describe showwe alter the base structure of germanium photodiodeobtained in last section and the results of how is thedark current affectedby themodificationNote that in followingsections including thisone simulationswillbeonly performed on the base structure with exponential defect profile which ismorephysicallysensibleThe terms that are frequently used are in table 2‐1 and Fig 2‐4 (Show again forconvenience)Terms MeaningshGe TotalthicknessofGermaniumdiode(=hov+hBody+hRec)hBody ThicknessofGermaniumbodyhov Thicknessofoverlap


Table 2‐1 Structural parameter of GePD

Fig 2‐4 Structure of germanium photodiode

27

Fig 3‐5 Simulated dark current as a function of Total Ge thickness

InthesimulationofdefectsuniformlydistributedinGelayerwithconstantdensityalineardependencebetweendarkcurrentat‐052voltandtotalGethicknessisseenThis is becausewith thicker Ge layer the number of uniformly distributed defectsalsoincreaseswhichresultsinmorecarriersgeneratedthroughdefects First hBody hov and hRec are altered while holding doping energy dopingconcentrationanddopingseparation(Wi)fixedResultsshowinFig3‐5InFig3‐5wecanseethatforbothconstantandexponentialcasedarkcurrentmerelychangedbyalittleamountashBodyhovandhRecarealteredtherearenohugedifferenceaslong as the total thickness of germanium is the same ie hGe=hRec+hBody+hov is thesame In other words what really affects dark current is the total thickness ofgermaniumnotthethreeindividualparametersBesides the slope of exponential defect profile data‐set is apparently smaller thantheslopeconstantdefectprofilehowevertwoofthemincreaseasgermaniumgetsthickerThis is canbeexplainedby thatwith larger thickness thenumberof trapsincreases since the volume of germanium increases so there are more SRHgenerationhappeninthatdiodeAs for the reason that current grows slower in the diode with exponential defectprofileitcanbeseeninFig3‐6whichshowsthattrapnumberislessinexponentialdensityprofileashGeisover06microm

28

Fig 3‐6 Trap number comparison between constant and exponential defects

29

332Alterationsinwidth

Astoalterationsinwidthparameterstheeffectsofwidthofgermaniumbody(wGe)anddopingseparation(Wi)ondarkcurrentarediscussedinthissectionInFig3‐7itshowseffectsofwidthofgermaniumondarkcurrentsindeviceswiththreedifferentthicknesseswhileholdingWiandotherparametersfixedAtrendcanbe seen that dark current is lower as wGe is at around 3 microm to 4 microm for eachthickness

Fig 3‐7 Effects of the width of germanium on dark current

Fig 3‐8 shows the behavior of dark current corresponding to differing dopingseparations (Wi) Dark current increases as doping separation getswider and thechange is much larger than the effect of thickness or width of germanium(wGe)SimilartrendsshowinsampleswithdifferentthicknessNotethatx‐axisofFig3‐8istheratioofWioverwGesothateffectsofwGeisexcluded

30

Fig 3‐8Dark current of different diodes versus doping separation ratio

Foraphotodiodewith fixedwGewhenWigetswider traps in intrinsic regionareuncoveredbydoping regionswhere carrier concentrationsareveryhighAlthoughthepeakvalueofelectric fielddecreasesas intrinsicregiongetswiderundersamebias (seeFig3‐9)dark current still rampsupas longasmoreandmore trapsareexposedoutandlocatedataratherhighfieldregionToconcludethelocationoftrapsiscriticalWhenthenumberoftrapsthatlocatedatlargeelectricfieldregionisincreasednotonlythegenerationsitesareincreasedthegenerationprocessbecomesmoreseverelyaswell

31

Fig 3‐9 Electric field distribution in diodes with different doping separation

32

333Alterationsinimplantenergy

Implant energy determines junction depth Fig 3‐10shows dark current ofgermanium photodiode as a function of implant energy (presented in EE0 ratiowhere E0 is the original implant energy) Dark current becomes higher whenjunctions become shallower In Fig 3‐11 it can be seen that as junction depthdecreases electric field spreads out more such that it promotes SRH generationprocess

Fig 3‐10 Dark current versus implant energy ratio

Fig 3‐11 Electric field distribution of diodes with different junction depth

33

34Conclusion

In this chapter TCAD simulation is involved In the beginningmodels used in oursimulation are introduced including SRH model Then base structures withestimated defect density are built via TCAD sprocess tool the estimated defectdensitiesare5e18cm3and1e20cm3forsimulationsofconstantdefectprofileandexponential defect profile respectively Finally we make alteration in the basestructureandshowanoptimumstructurethathasminimumdarkcurrentGenerally speaking to make a germanium photodiode with low leakage a thingermaniumlayerisrequiredtoreducetheSRHvolume(numberoftraps)asmuchaspossible anarrowdoping separation is crucial tokeepa small SRHvolumewithinthis largeelectric field region and finallydeep junctionsareneeded to circumventthespreadingelectricfield

34

35

Chapter4 QuantumEfficiency

OptimizationIn this chapter an optical signal in implanted into the base structure obtained inchapter 2 as an input to simulate the illuminated photodiode Optical generationmethod and definition of quantum efficiency (QE) are given And again we makealteration inthebasestructureandshowanoptimumstructurethathasmaximumquantumefficiency

41OpticalGenerationanddefinitionofQuantumEfficiency

411OpticalGenerationMethod

As shown in Fig 4‐1 a two‐dimensional single‐mode light intensity distribution ofinfraredopticalsignalat1550microminsideatwo‐dimensionGermaniumstructureof2‐μm‐wide and 02‐μm‐thick was obtained beforehand by using the commercialpropagation tool FIMMWAVE by Photon Design (Photon Design Inc Oxford UK)FIMMWAVEisafullyvectorialmodefinderwhichprovidesrigoroussolutionstothefullMaxwellequationsItcanquantitativelysimulatethemodalbehaviorandopticalpropertiesinsidewaveguidesofarbitrarymaterialandofalmostanyshape

Fig 4‐1 The 2Dsingle‐modeinfrared light intensity distribution inside a 2D Germanium structure of 2‐μm‐wide and 02‐μm‐thick

36

FromtheresultobtainedbyFIMMWAVE the intensitydistribution is found tobeatwo‐dimensional Gaussian form with specific variance (σx2σy2) Then opticalcommand codes expressed by two‐dimensional Gaussian are added in TCADsimulator(codesinappendix)tomimiconephotoninGePDandthenumberweusein the following optimization simulations is 1e15 (cm‐3s‐1)Fig 4‐2 shows theillustrationof light intensity in2DGaussian formand theGePD cross‐section afteropticalsignalispluggedin

Fig 4‐2 Two‐dim Gaussian optical signal in the TCAD simulator (Top) Illustration of light intensity in 2D Gaussian form (bottom) GePD cross‐section after optical signal is plugged in

37

412DefinitionofQuantumEfficiency(QE)

Quantum Efficiency(QE) or external quantum efficiency (EQE) is defined by theratio to the number of incident photons of a given energy over the number ofelectrons that collected by photodiode which is shown at Eq 4‐1The value ofquantumefficiencyindicatestheabilityofaphotodiodetotransferopticalsignalintoelectricalsignalandcollectthem

EQEnumber of electronssecnumber of photonssec

Eq 4‐1

Anothertypeofquantumefficiencyisinternalquantumefficiency(IQE)whichisnotused in the evaluation of our simulated photodiodes The value IQE indicates thephotontransmissionabilityofphotodiodeswhichisnottheissueconcernedinthisthesis

38

42QEinrespectofStructuralparameters

Alterationsaredonemainlyintotalthicknessofgermaniumwidthofgermaniumandthedopingseparation

421QEdependenceonthicknessandwidthofGePD

InFig4‐3 lightdistributioninphotodiodeswithvariousgeometries isshownOnecansee insmallGePD light intensityconcentrates inthemiddleof thephotodiodewhere electric field is the largest This is beneficial because the generated carrierscanbequicklyswepttoelectrodesbythestrongelectricfieldbeforetheyrecombineHowever thereare also lostof lights since someof lightsdistribute intooxideandsiliconAndinthecaseofwidedeviceslightdistributionbroadensoutsoaveragelythenumberofcarriersgeneratedbyphotonsthatexperiencelargeforceisreduced

Fig 4‐3 Light distribution in photodiodes with different width and thickness

AsaresultwecanexpectanoptimumhappenataspecificgermaniumthicknessandwidthAsshowninFig4‐4maximumvaluehappensatthicknessof05micromandtotalGewidthof34to45microm

39

Fig 4‐4 Effects of Ge thickness and width on QE

40

422QEdependenceondopingseparation

Inthissectionphotodiodesincludingdifferentdopingseparation(Wi)aresimulatedwiththeGePDobtainedinprevioussectionthathavelightsmostlyconcentrateinthemiddleandalsobeenclosedinsidegermaniumlayerThewidthofdopingseparationdetermines firstly the window that enables electric field to act on generatedelectronsandholesandsecondlythestrengthoftheelectricfieldAlargeWiindicatesalargewindowtocapturelightneverthelesswehaveshowninFig3‐9(showagainbelow)thatelectric fielddecreasesasWi increasesThat isweshouldmakeWilargeenoughtocapturesufficientlightbutnotsolargethatelectricfield becomes too weak to drive electrons and holes to electrodes before theyrecombine


Fig4‐5showshowQEdependsondopingseparation Itcanbeseenthatquantumefficiency reaches a maximum when Wi is 50 to 60 of the total width ofgermanium

41

Fig 4‐5 QE dependence on doping separation

42

43QEimprovementbyJunctionengineering

Fromtheresultsofchapter3andprevioussectionsinthischapteroneseesthereisinevitabletrade‐offbetweenlowdarkcurrentandhighQEInthischapterjunctionsengineeringisperformedandattemptedtomaintainorincreasequantumefficiencyatthesametimekeepingdarkcurrentatalowlevelTominimizingdarkcurrentwithagivendensityoftrapsitisimportanttoseparatetrap locations fromwhereelectric field ishighSince trapsmostlydistributeat thebottomof germanium layermaking junctions shallower seemsable to achieve thisgoal However previously in Fig 3‐10(would be shown again later) we found thatdarkcurrentrisesasjunctiondepthdecreasesduetoelectricfieldspreadsoutmorein a shallow junction Fig 4‐6 shows the simulation results of decreasing junctiondepthusingoriginalimplantationmethodandtrade‐offisseenbetweenlowleakageandhighQE

Fig 4‐6Dark current and QE as a function of implant energy

(E0 is the original implant energy E is the variable)

Consequently a two‐step implantation without extra masks is introduced intosimulator as the first implantation to form a deep junction with small dopingconcentration and the second one to form a shallow junction with high dopingconcentrationThe functionofdeep junction is to screenout thespreadingelectricfield from the shallow junction while it itself provides very small electric field sothat SRH process through traps at the bottom of GePD wouldnrsquot be very strongIllustrationofdeep‐and‐shallowdopingandthesimulatedstructurewithEE0=02areinFig4‐7

43

Fig 4‐7 Deep junctions and shallow junctions

Results of simulation of deep‐and‐shallow junctions are in the following Fig 4‐8shows dark current and QE as a function of shallow doping dosages and a set ofcurvesdifferingbydeepdopingdosage ispresentedShallowdopingconcentrationcanbeasheavyasactivationmaximum(forgermaniumisapproximately1e19cm3)since high QE is achieved without promoting dark current Dark current issuppressedcomparedtothatofstructurewithoutthesecondstepdeepdopingandimplantationdoseof3e13cm2ischosentobetheoptimumdopingconcentrationfordeepjunctionDosesaslowas5e12cm2fordeepdopingcannotsufficientlyscreenout theelectric fields formshallow junctionsanddeep junctionswithdoses largerthan3e13cm2mightprovideitsownelectricfieldandresultedindarkcurrentrisingsuchasthebehaviorofdeviceswith5e13cm2(redlinewithsquare)

Fig 4‐8 Effects of deep‐and‐shallow junctions on dark current and QE

44

44Conclusion

Hereinchapter4westarttosimulatethephotocurrentofGePDwithopticalsignalsOptical signal is generated by putting the Gaussian form calculated by waveguidemodalsolverTohavehighquantumefficiencywehaveanoptimumwiththewidthofgermaniumequals to 34 microm the thickness of germanium equals to 05 microm and the dopingseparationequalstohalfofthewidththatis17micromTomaintainhighquantumefficiencywhilekeepinglowlevelofdarkcurrentdeep‐and‐shallow junction is proposed Deep junction is doped slightly 3e13cm2 tosuppressdarkcurrentandshallowjunctionisdegeneratelydopedtopromptphotocurrentsTheoptimumstructure is shown inFig 4‐9where the color legend is fordopantsanddefectconcentrationandroundcontoursisillustratingtheopticalsignalinsideGePD

Fig 4‐9 The optimum structure for low dark current and high QE

45

Chapter5 TransientResponse

OptimizationIn this chapter the transient respond of photodiode to an optical pulse signal ispresentedandtheparasiticcapacitanceofoursimulatedphotodiodewithoutopticalsignal isobtainedbyC‐Vsimulation InthefollowingsectionsanequivalentcircuitofGePD isgiven the issueof the lengthof thephotodiode isdiscussed and finallyfrequencyresponseofsimulatedphotodiodeisshownrespectively

51TheRoleofTransientResponse

The significant growth in computer processing power due to microelectronicsscalingrequiresacorrespondingincreaseincommunicationbandwidthForon‐chipapplications detectors with very small capacitance and high speed are crucial forlowpowerlargebandwidthsystems[17]To estimate the transient behavior intrinsically fromGePDdevice an optical pulsesignalisintroducedintotheTCADsimulatorwhilethesimulatedphotodiodesareintheoperationpoint ‐05VNextwe characterize the speedof simulated germaniumphotodetector in a unit of GHz by calculating the inverse of RiseTime which isdefinedbyThetimerequiredfortheresponsetorisefrom10to90of its finalvalueAsshowninFig5‐1

Fig 5‐1 Illustration of rise time definition

To estimate the input‐output transient respond from the systempoint of view Fig5‐2showstheequivalentcircuitofaP‐i‐Nphotodiode

46

Aphotodiode is regardedasacurrent sourcewithparasitic leakageresistanceandjunction capacitance and parasitic capacitance resistance and inductance ofinterconnectwouldalsocontributetoRCtimedelayAsIph ischangingwiththeAC

optical signal the voltagendashdrop across is Rs also changing and this leads to thechargingdischarging behavior of CPD and CPThe ultimate goal is to acquire anequivalentcircuitmodelofGePDandafterseeingtheintrinsicspeedofGePDswithdifferent geometry in section52 thevalueof componentCPD is obtained fromC‐Vsimulationinsection53

Fig 5‐2 Effective circuit of a PIN photodiode[20][21]

47

52Speedinrespectofstructuralparameters

Inthissectiontheeffectsofdopingseparation(Wi)andwidthofgermanium(wGe)onthephotodiodecapacitanceandspeedarediscussedC‐VcharacteristicsimulationisfirstperformedonphotodiodeswithdifferentWiandwGewithoutinjectingopticalsignalSubsequentlyanopticalinputwithpulsewidthequals to1nanosecond is introduced into theelectrical characterization section insimulator and then speed (GHz) is calculated via rise time of the respondscorrespondingtoeverydeviceFig 5‐3 shows the C‐V characteristics of simulated photodiode with variousstructuresandoneseesfromFig5‐3(a)thatcapacitanceincreasesdramaticallyasWi decreases and from Fig 5‐3 (b) capacitance increases as hGe increases whilewGeplayslittleroleincapacitanceItisquitereasonablewhenseeingawell‐knowncapacitanceformulaeEq5‐1(NotethatcapacitanceisintheunitofFaradspermicrombecauseofthetwo‐dimensionalsimulation)

C Fμ εCapacitor Area

Capacitorthicknessε

hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)

Fig 5‐3 C‐V characteristics of simulated photodiode with various structures

However in Fig 5‐4speed dependencies on wGe appear to have an inverse linearrelation despite the fact that wGe has little contribution to parasitic capacitance(NotethatWiisfixed)Itcanbeexplainedbythetransitiontimeforcarrierstotravelto electrodes since there is a longer distance for electrons that generated in themiddleofGePDtobedriven tocathode inaratherwidephotodiodeviceversa forholes

Fig 5‐4 Speed of GePD is inversely proportional to wGe

InFig5‐5 speedabove30GHz is achieved in thedevicewGeequals to2micromwithdoping separation equals to 12 microm The photodiode with the structure whichprovidesbestquantumefficiencyisindicatedaswellSpeeddistributionoverdoping

49

separationisprettysharpandtwomachismoscompetingwitheachotherAtregionI speed isaffectedby the large junctioncapacitancewhenWi issmall Inregion IIspeedislimitedbythetransitionvelocityofcarrierssinceelectricfielddecreasesWiincreases

Fig 5‐5Speed evaluation of GePDs with different Wi and wGe

50

53Lengtheffect

In previous chapters simulations are all done in a two‐dimensional germaniumphotodiodethereforeinthissectionweconsidertheeffectsofthelength(LGe)onphotodiode (L is shown inFig 2‐4) including the capacitance and the absorptionefficiencyoflightsinlongandshortdevices

531Capacitanceinlengthdirection

First estimation of transient respond of germaniumphotodiode is required from asystem level point of view To reduce RC delay the capacitance of germaniumphotodetector for interconnect systemshouldalwaysbeminimized Fig 5‐6 showsthe parasitic capacitance CPDat ‐05V In the structure of GePD in this thesis thelength of electrodes is approximately same with the length of implant junctionsSincecapacitanceisincreasingwiththeGePDlengthashortgermaniumphotodiodeisdesirableforbothloweringCPDandpadcapacitanceCP

Fig 5‐6Parasitic Capacitance CPDobtained with length of GePD

51

532Absorptioninlengthdirection

From the transmission point of view absorption coefficientmeasures how quicklythe lightsignalwould lose intensitydue to theabsorptionofamaterialButas forphotodiode themore lights absorbedmeans themore photons can be utilize andcontributetocarriersInFig5‐7theopticalabsorptionofcrystallineSi1‐xGexandthecorrespondingindexofrefractionofeachmaterialareshownfromtheliterature[22]

Fig 5‐7 Optical absorption coefficient of Si Ge and SiGe alloys[22]

Based on Beer‐Lambert law (Eq 5‐2) where I I0 and α are intensity at L inputintensityandabsorptioncoefficientrespectivelytheabsorptionrationasafunctionofthelengthofgermaniumphotodiodecanbecalculatedasshowninFig5‐8Highabsorption ration means that there are more number of photons that can betransferred into carriers so photo‐current would increase (Note that QE doesnrsquotchange)

I I ∙ e Eq 5‐2

52

Fig 5‐8 Absorption ratio versus length of germanium photodiode

As a result this section reminds that in realist case although we prefer a shortphotodiode to avoid large capacitance the length of germanium photodiode stillneedstobecompromisedwiththeabsorptionefficiencyoflightsignals

53

54Frequencyresponse

541Bitstreaminput

As an input the bit stream below in Fig 5‐9is pseudo random and has the mostimportanttransitionsbecauseitincludesallthecombinationsofthreebits

Fig 5‐9 The bit stream input contains combinations three bits

542Eyediagram

Toevaluate systemspeed eyediagramsareoftenusedAnopeneye interprets thenicetransientrespondofanelectronicdeviceInFig5‐10simulationsoftransientsrespondstothebitstreaminputswithfrequencies1GHz10GHz20GHz40GHzand100GHzareperformedA regular trendcanbe seen thatas the signal frequency ishigher than thespeed thatGePDcanhandlewith signalsdistortioncanbereadasthe ldquoeyerdquogetting closed In realistic cases eyediagramsneeds tobeextendedwithparasitic components noises and loads of amplifiers depending on variousinterconnectsystems

54

Fig 5‐10 Eye diagram of the GePD with speed 30GHz

55

55Conclusion

InthischapteritisseenthatthespeedofGePDincreaseswiththetotalwidth(wGe)while foreachwGethere isanoptimumdopingseparation(Wi)valueAmaximum32GHzisfoundatwGeequalsto2micromandWiequalsto02micromForoptimizationinlengthdirectionweshouldnotethatlengthofGePDneedstobecompromisedwiththeabsorptionefficiencyoflightsignalsandthejunctioncapacitanceValue of junction capacitance of GePD with different length is obtained by C‐Vsimulation The simulation of C‐V might seem redundant since capacitance is ofcourseincreasinglinearlywitheffectivecapacitorarea(hGetimesLGe)butithelpsustodemonstrate the model of equivalent circuit of GePD which would be shown inchapter6Finally frequency respond is shown in eye diagramswhile a bit stream of opticalsignalwithvariousfrequencies

56

57

Chapter6 ConclusionAs one of the crucial components in optical interconnect system germaniumphotodiodes are promising due to its corresponding bandgap to absorb infra‐redlight and the compatibility to silicon‐based photonics and electronics Howevermany researchers have shown that GePD is suffering from high dark current andefforts were done to suppress the dark current and to increase gain‐bandwidthproductbyimprovingGePDefficiencyandspeedSeveralguidelinestowardtheGePDstructureareprovidedinthisthesiswiththeaidof investigationofmeasureddarkcurrentandTCADsimulation tohelp fabricatinghigh‐efficiency and low‐power consumption germanium photodetector with thestructure resembles following figureA table of guidelines is put at the endof thischapterafterstatementsofconclusionschapterbychapter

In chapter 2 we show the investigation of physical mechanisms behind the darkcurrentingermaniumphotodiodeviaexperimentaldataItcanbeverifiedthatdarkcurrent is in thecombinationbehaviorofdiffusioncurrentandShockley‐Read‐HallgenerationcurrentAtroomtemperatureandatthebias‐05VSRHgenerationisthemain component in dark current There is a good qualitative agreement betweenformulatrendandmeasureddataIn chapter 3 TCAD simulation is involved with inclusion of SRH model WeconstructedbasestructuressimilartomeasuredphotodiodesinTCADsprocesstoolwith defect densities are estimated as 5e18cm3 and 1e20cm3 for simulations ofconstantdefectprofileandexponentialdefectprofileAlterationsweremade inthebase structures to find the structure that has minimum dark current Generallyspeaking to make a germanium photodiode with low leakage a thin germaniumlayerisrequiredtoreducetheSRHvolumeienumberoftrapsasmuchaspossibleAnarrowdopingseparation iscrucial tokeepasmallSRHvolumewithin the largeelectric field region Finally deep junctions (junction depth asymp hGe) are needed tocircumvent the dark current arouse by the spreading electric field of shallowjunctions

58

Inchapter4westart tosimulatethephotocurrentofGePDwithopticalsignalsTohavehighquantumefficiencywehave an optimumwhen thewidth of germaniumequals to 34 microm the thickness of germanium equals to 05 microm and the dopingseparation equals tohalf of thewidthwhich is17micromTomaintainhighquantumefficiency while keeping low level of dark current deep‐and‐shallow junction isproposedDeepjunctioniswithslightlydoping3e13cm3tosuppressdarkcurrentand shallow junction is degenerately doped to prompt photo currents The finalGePDstructurewithoptimizedgeometriesandjunctionengineeringisshownbelowwherethecolorlegendisfordopantsanddefectconcentrationandroundcontoursisillustratingtheopticalsignalinsideGePD

Inchapter5transientrespondofGePDtoACopticalsignalispresentedThespeedincreases as totalwidth (wGe)decreaseswhile for eachwGe there is an optimumdoping separation (Wi) valueAmaximum32GHz is found atwGe equals to 2 micromandWiequals to02micromForoptimization in lengthdirectionweshouldnote thatlength of GePD needs to be compromised with the absorption efficiency of lightsignalsandthejunctioncapacitanceThevalueofjunctioncapacitanceofGePDwithdifferent length is obtained by C‐V simulation to demonstrate the model ofequivalentcircuitofGePDTosummarizethewholethesiscontributionsfromabovechaptersaregeneralizedintwoaspectsasdescribedinthefollowingtwoparagraphsIn device aspect we provide guidelines toward the GePD structure which aresummarized above and arranged in Table 6‐1on next page Each parameter isdiscussedwhileothersarefixedInsystemaspectweprovideasimulationframeworksuchthatvaluesofelectroniccomponents in the equivalent circuit of GePD become available or computable Inthis way evaluation of speed at the system level could be achieved by applyingequivalent circuit of germanium photodiode connects to arbitrary knowninterconnection systems For a germanium photodiode with length L componentscanbeobtainedasshowninTable6‐2

59

Parameters Guidelines ReasonsTolowerDarkcurrent

hGe SmallerbetterIdark increases linearly with hGe due tonumberoftrapsincreasesasgermaniumhasalargervolume

wGege3microm

(Wi=18microm)

For same Wi many traps at the taperedfacets are more close to the middle in anarrowGePDwhereelectricfieldisstronger

Wi SmallerbetterNumber of traps increases at the intrinsicregionwhereelectricfieldislarge

Junction DeeperbetterElectric field spreading out from shallowjunctionwouldincreaseIdark

ToincreaseQuantumefficiencyhGe 05microm Theoptimumreachedinthestructurewhich

lights mostly contribute in the center ofGePD while not being squeezed out ofgermanium

wGe 34microm

Wi frac12ofwGe

Junction ShallowerbetterStrong electric fields from shallow junctionimproveQE

LowDarkCurrentandHighQEatsametime

Optimizedgeometryand

Deep‐and‐shallowtwo‐stepsimplant

Strong electric field of shallow junctions isawayfromdefectsatbottomofGePDanditprovides a strong driven force to carriersDeep junctionwith slightdopingcan screenthe electric fields spreading from top todefectsatthebottom

Toboostspeed

LGe DependsonapplicationLinfluencesabsorptionoflightandparasiticcapacitance

wGe SmallerbetterNarrow GePD means shorter distance forcarrierstotraveltoelectrodes

WiTheoptimumexistsdependingonwGe

MaximumhappenedatdifferentWivaluesinGePDwith differentwGe because there aretwo mechanisms competing each otherJunctioncapacitanceanddriftvelocity

Table 6‐1 Several Guidelines for designing GePD

60

Components Resource Expression

Iph(A) Ch4ofthisthesis Photonsabsorbed(L)timesQE(ratio)

RP(ohm) Ch2Ch3ofthisthesis Vbias(V)Idark(Amicrom)timesL(microm)

CPD(Farads) Ch5ofthisthesis AssimulatedinSec531

CPLPRS Estimatedfromcircuitlayout

RL Dependsonnextcircuitstage(amplifieretc)

Table 6‐2GePD equivalent circuit [20][21]and acquired value of components

61

Appendices

62

63

AppendixACommandcodesinTCADsimulatorIn thisappendix commandcodesused inTCADSprocessTCADSdevicesimulatorsare given Note that here ldquohGerdquo stands for hbody only not the total germaniumthickness

Sprocess

definegarden01definehOX[expr(hov+hGe)]defineWtot[expr(2(wov+$garden)+wGe)]definetheta[expr(314159265angle180)]definewPN[expr(wGewPN_ratio)]defineimp_long[expr(($wPN+$Wtot)2)]linexloc=0tag=SiTopspacing=50ltnmgt linexloc=300ltnmgttag=SiBottomspacing=50ltnmgt lineyloc=0tag=SiLeftspacing=50ltnmgt lineyloc=$Wtottag=SiRightspacing=50ltnmgt regionsiliconxlo=SiTopxhi=SiBottomylo=SiLeftyhi=SiRight initconcentration=1e15field=BoronDelayFullD mgoalsonminnormalsize=2ltnmgtmaxlateralsize=2ltumgtnormalgrowthratio=13 PHYSICALMODELSFORGERMANIUM pdbSetDoubleImplantDataGermaniumAtomicMass7261 pdbSetDoubleImplantDataGermaniumAtomicNumber32 pdbSetDoubleGermaniumLatticeConstant564613 pdbSetDoubleGermaniumLatticeDensity441e22 pdbSetDoubleGermaniumAmorpGamma10 pdbSetDoubleGermaniumAmorpDensity11e22 pdbSetDoubleGermaniumAmorpThreshold11e22 pdbSetDoubleGermaniumLatticeSpacing[exprpow(1441e221030)] pdbSetStringGermaniumLatticeTypeZincblende pdbSetDoubleGermaniumMassDensity535 pdbSetBooleanGermaniumAmorphous0 pdbSetStringGermaniumLatticeAtomCOMPOSITION pdbSetStringGermaniumCompositionComponent0NameGermanium pdbSetDoubleGermaniumCompositionComponent0StWeight1 pdbSetDoubleGermaniumCompoundNumber1 pdbSetDoubleGermaniumDebyeTemperature519

64

pdbSetBooleanGermaniumElectronicStoppingLocal1 pdbSetDoubleGermaniumSurfaceDisorder5e‐4 NUMERICALPARAMETERSFORTaurusMC(pleaseconsultmanual) pdbSetMCImplantTrajectoryReplication1 pdbSetMCImplantTrajectorySplitting1 pdbSetDoubleGermaniumPhosphorusMaxSplits80 pdbSetDoubleGermaniumPhosphorusMaxSplitsPerElement10 pdbSetDoubleGermaniumBoronMaxSplits80 pdbSetDoubleGermaniumBoronMaxSplitsPerElement10 pdbSetDoubleGermaniumArsenicMaxSplits80 pdbSetDoubleGermaniumArsenicMaxSplitsPerElement10 MonteCarloImplantparamertersimplantedspecies(TaurusMC) pdbSetDoubleGermaniumPhosphorusamorpar10 pdbSetDoubleGermaniumPhosphoruscascamo10 pdbSetDoubleGermaniumPhosphorusdispthr15 pdbSetDoubleGermaniumPhosphoruscascdis15 pdbSetDoubleGermaniumPhosphorussurvrat075 pdbSetDoubleGermaniumPhosphoruscascsur075 pdbSetDoubleGermaniumPhosphorusMCVFactor10 pdbSetDoubleGermaniumPhosphorusMCDFactor10 pdbSetDoubleGermaniumPhosphorusMCIFactor10 pdbSetDoubleGermaniumBoronamorpar10 pdbSetDoubleGermaniumBoroncascamo10 pdbSetDoubleGermaniumBorondispthr15 pdbSetDoubleGermaniumBoroncascdis15 pdbSetDoubleGermaniumBoronsurvrat0225 pdbSetDoubleGermaniumBoroncascsur0225 pdbSetDoubleGermaniumBoronMCVFactor10 pdbSetDoubleGermaniumBoronMCDFactor10 pdbSetDoubleGermaniumBoronMCIFactor10 pdbSetDoubleGermaniumBoronLSSpre125 pdbSetDoubleGermaniumBoronnlocexp0075 pdbSetDoubleGermaniumBoronnlocpre044 pdbSetDoubleGermaniumBoroncascsat002 pdbSetDoubleGermaniumBoronsatpar002 THESE PARAMETERSmakesB only partially amorphizing inGermanium damagesaturateswhen2oflatticeatomshavebeen displacedThisnumberisbasedonLIMITEDSIMSdata andshouldbeconsideredanestimate pdbSetDoubleGermaniumArsenicamorpar10 pdbSetDoubleGermaniumArseniccascamo10 pdbSetDoubleGermaniumArsenicdispthr15 pdbSetDoubleGermaniumArseniccascdis15 pdbSetDoubleGermaniumArsenicsurvrat2 pdbSetDoubleGermaniumArseniccascsur2 pdbSetDoubleGermaniumArsenicMCVFactor10 pdbSetDoubleGermaniumArsenicMCDFactor10 pdbSetDoubleGermaniumArsenicMCIFactor10 pdbSetDoubleGermaniumArsenicLSSpre1 pdbSetDoubleGermaniumArsenicnlocexp0075 pdbSetDoubleGermaniumArsenicnlocpre05

65

1_oxide_pattertn mask maskname=hovleft=‐0001right=01maskname=hovleft=$Wtot‐$gardenright=$Wtot+0001maskname=hGeleft=‐0001right=01+wovmaskname=hGeleft=$Wtot‐$garden‐wovright=$Wtot+0001 depositmaterial=Oxidetype=isotropicthickness=$hOX etchmaterial=Oxidetype=anisotropicthickness=hovmask=hov etchmaterial=Oxidetype=anisotropicthickness=[expr(hGe+0001)]mask=hGe 2_silicon_etch_back X10defineY1[exprwov+$garden]defineY2[expr$Y1+hRectan($theta)]defineY3[expr$Wtot‐$Y2]defineY4[expr$Wtot‐$Y1]etchmaterial=Silicontype=polygonpolygon=0$Y1hRec$Y2hRec$Y30$Y40$Y13_GermaniumGrowth depositmaterial=Germaniumtype=fillcoord=‐$hOX4_N++implant(masked) maskclear maskname=N_impleft=‐1ltnmgtright=$imp_longnegativemaskname=N_impleft=[expr($Wtot‐$garden)]right=[expr($Wtot+0001)]negative depositmaterial=Nitridetype=anisotropicthickness=1000ltnmgtmask=N_imp implantPhosphorusdose=5e14ltcm‐2gtenergy=80ltkeVgtsentaurusmcinfo=1 stripNitride 5_P++implant(masked) maskclear maskname=P_impleft=‐1ltnmgtright=$gardennegative maskname=P_impleft=[expr($Wtot‐$imp_long)]right=[expr($Wtot+0001)]negative depositmaterial=Nitridetype=anisotropicthickness=1000ltnmgtmask=P_impimplantBorondose=5e14ltcm‐2gtenergy=30ltkeVgtsentaurusmcinfo=1 stripNitride selectz=(min(Phosphorus2e19)‐min(Boron1e19))name=DopingConcentrationstoreselectz=(DopingConcentration)name=Netactivestore(ifDtype==con puts selectGermaniumz=(Phosphorus+Boron+Dpeak)name=TotalConcentrationstore selectSiliconz=(Phosphorus+Boron)name=TotalConcentrationstore else

66

puts select Germanium z=(Phosphorus+Boron+Dpeakexp(‐(hRec‐x)002))name=TotalConcentrationstore selectSiliconz=(Phosphorus+Boron)name=TotalConcentrationstore )6_Contactformationcontactmaskmaskclearmaskname=contactleft=‐1ltnmgtright=[expr($garden+005)]maskname=contactleft=[expr($garden+005+035)]right=[expr($Wtot‐($garden+005)‐035)]maskname=contactleft=[expr($Wtot‐($garden+005))]right=[expr($Wtot+0001)] depositmaterial=Oxidetype=anisotropicthickness=250ltnmgtetchmaterial=Oxidetype=anisotropicthickness=251ltnmgtmask=contact depositmaterial=Aluminumtype=fillcoord=[expr(‐1($hOX+025))] contactname=anodeAluminumx=[expr(‐1($hOX+01))]y=[expr($garden+005+01)]replacepoint contact name=cathode Aluminum x=[expr (‐1($hOX+01))] y=[expr ($Wtot‐($garden+005+01))]replacepoint7_opticalGaussianprofilesetC1[expr(008653022)]setC2[expr(0400182)]setsigmaX[expr((hov+hGe+hRec)$C1)]setsigmaY[expr((2($garden+wov)+wGe)$C2)]setrX[expr((hov+hGe+hRec)2)‐hRec]setrY[expr($garden+(wGe+wov+wov)2)]select z=(1e12($sigmaXsqrt(2314159))exp(‐(x+$rX)(x+$rX)(2$sigmaX$sigmaX))1($sigmaYsqrt(2314159))exp(‐(y‐$rY)(y‐$rY)(2$sigmaY$sigmaY)))name=OpticalGenerationstorestructtdr=nnodeGasexit

67

SdeviceforIV

FileinputfilesGrid=tdrParameter=imecusershellingspublicDoctoraatTCADotherprojectstablesJan2010Germanium_hellings_v2parOpticalGenerationInput=tdroutputfilesPlot=tdrdatCurrent=plotOutput=logElectrodeName=anodeVoltage=00Name=cathodeVoltage=00PhysicsMobility(DopingDependence)Recombination(SRH(DopingDependenceElectricField(Lifetime=HurkxDensityCorrection=None)))Optics(OpticalGeneration(ReadFromFile(DatasetName=OpticalGenerationScaling=1)))Plot‐‐DensityandCurrentsetceDensityhDensityTotalCurrentVectoreCurrentVectorhCurrentVectoreMobilityhMobilityeVelocityhVelocityeQuasiFermihQuasiFermi

68

‐‐TemperatureeTemperaturehTemperatureTemperature‐‐FieldsandchargesElectricFieldVectorPotentialSpaceCharge‐‐DopingProfilesDopingTotalConcentrationDonorConcentrationAcceptorConcentration‐‐GenerationRecombinationSRHRecombinationAugerBand2BandGenerationAvalancheGenerationeAvalancheGenerationhAvalancheGeneration‐‐DrivingforceseGradQuasiFermiVectorhGradQuasiFermiVectoreEparallelhEparalllel‐‐BandstructureCompositionBandGapBandGapNarrowingAffinityConductionBandValenceBandxMoleFraction‐‐TrapseTrappedChargehTrappedChargeeGapStatesRecombinationhGapStatesRecombination‐‐HeatgenerationTotalHeateJouleHeathJouleHeatRecombinationHeatOpticalGenerationOpticalIntensityMathError(Electron)=1e‐5Error(Hole)=1e‐5RelErrControlErrRef(Electron)=1e12ErrRef(Hole)=1e12ExtrapolateTrapDLN=100eDrForceRefDens=1e12hDrForceRefDens=1e12NoSRHperPotentialhMobilityAveraging=ElementEdgeeMobilityAveraging=ElementEdgeSolve

69

‐CreatinginitialsolutionCoupled(Iterations=100)PoissonCoupled(Iterations=100LineSearchDamping=001)PoissonElectronHole‐RamptonegativebiasQuasistationary(InitialStep=025Increment=12Decrement=4MinStep=1e‐4MaxStep=1GoalName=anodeVoltage=‐1) Coupled(Iterations=15 ) Poisson Electron Hole Plot (FilePrefix =nnode_Dark_05Time=(05))NewCurrentFile=sweepdark_Plot(FilePrefix=nnode_dark)‐RamptopositivebiasQuasistationary(InitialStep=004Increment=12Decrement=4MinStep=1e‐4MaxStep=004GoalName=anodeVoltage=1)Coupled(Iterations=15)PoissonElectronHoleNewCurrentFile=sweeplight_Plot(FilePrefix=nnode_light)‐switchonthelightQuasistationary(InitialStep=1Increment=12Decrement=4MinStep=1e‐4MaxStep=1Goal ModelParameter=OpticsOpticalGenerationReadFromFileScalingvalue=Iphg)Coupled(Iterations=15)PoissonElectronHole‐RamptonegativebiasQuasistationary(InitialStep=004Increment=12Decrement=4MinStep=1e‐4MaxStep=004GoalName=anodeVoltage=‐1) Coupled(Iterations=15 ) Poisson Electron Hole Plot (FilePrefix =nnode_Light_05Time=(075))

70

SdeviceforC‐V

DeviceDIODEElectrodeName=anodeVoltage=StartVoltageName=cathodeVoltage=00FileGrid=tdrCurrent=plotPlot=tdrdat Parameter=imecusershellingspublicDoctoraatTCADotherprojectstablesJan2010Germanium_hellings_v2parPhysicsMobility(DopingDep) Recombination(SRH(DopingDependenceElectricField(Lifetime=HurkxDensityCorrection=None)) )PloteDensityhDensityeCurrenthCurrentElectricFieldeEparallelhEparalleleQuasiFermihQuasiFermiPotentialDopingSpaceChargeDonorConcentrationAcceptorConcentrationConductionBandEnergyValenceBandEnergyMathError(Electron)=1e‐5Error(Hole)=1e‐5RelErrControlErrRef(Electron)=1e12ErrRef(Hole)=1e12ExtrapolateTrapDLN=100eDrForceRefDens=1e12hDrForceRefDens=1e12NoSRHperPotentialhMobilityAveraging=ElementEdgeeMobilityAveraging=ElementEdgeFileOutput=logACExtract=acplot

71

SystemDIODEGePD(anode=elect_pcathode=elect_n)Vsource_psetvp(elect_p0)dc=StartVoltageVsource_psetvn(elect_n0)dc=0Solve‐a)zerosolutionCoupledPoissonCoupledPoissonElectronHoleCoupledPoissonElectronHoleCircuitContact‐d)rampbottomcontactQuasistationary(InitialStep=MaxStepMaxStep=MaxStepMinStep=1e‐7GoalParameter=vpdcVoltage=TargetVoltage)ACCoupled(StartFrequency=1e6EndFrequency=1e6NumberOfPoints=1DecadeNode(elect_pelect_n)Exclude(vpvn) )PoissonElectronHoleCircuitContact

72

Sdevicefortransient

FileinputfilesGrid=tdrParameter=imecusershellingspublicDoctoraatTCADotherprojectstablesJan2010Germanium_hellings_v2parOpticalGenerationInput=tdroutputfilesPlot=tdrdatCurrent=plotOutput=logElectrodeName=anodeVoltage=00Name=cathodeVoltage=00PhysicsMobility(DopingDependence)Recombination(SRH(DopingDependenceElectricField(Lifetime=HurkxDensityCorrection=None)))Optics(OpticalGeneration(ReadFromFile(DatasetName=OpticalGenerationScaling=1)))Plot‐‐DensityandCurrentsetceDensityhDensityTotalCurrentVectoreCurrentVectorhCurrentVectoreMobilityhMobilityeVelocityhVelocityeQuasiFermihQuasiFermi‐‐TemperatureeTemperaturehTemperatureTemperature‐‐FieldsandchargesElectricFieldVectorPotentialSpaceCharge

73

‐‐DopingProfilesDopingTotalConcentrationDonorConcentrationAcceptorConcentration‐‐GenerationRecombinationSRHRecombinationAugerBand2BandGenerationAvalancheGenerationeAvalancheGenerationhAvalancheGeneration‐‐DrivingforceseGradQuasiFermiVectorhGradQuasiFermiVectoreEparallelhEparalllel‐‐BandstructureCompositionBandGapBandGapNarrowingAffinityConductionBandValenceBandxMoleFraction‐‐TrapseTrappedChargehTrappedChargeeGapStatesRecombinationhGapStatesRecombination‐‐HeatgenerationTotalHeateJouleHeathJouleHeatRecombinationHeatOpticalGenerationOpticalIntensityMathError(Electron)=1e‐5Error(Hole)=1e‐5RelErrControlErrRef(Electron)=1e12ErrRef(Hole)=1e12ExtrapolateTrapDLN=100eDrForceRefDens=1e12hDrForceRefDens=1e12NoSRHperPotentialhMobilityAveraging=ElementEdgeeMobilityAveraging=ElementEdgeSolve‐CreatinginitialsolutionCoupled(Iterations=100)PoissonCoupled(Iterations=100LineSearchDamping=00001)PoissonHoleElectron‐RamptonegativebiasQuasistationary(InitialStep=025Increment=12Decrement=4MinStep=1e‐4MaxStep=1

74

GoalName=anodeVoltage=‐05) Coupled(Iterations=15 ) Poisson Electron Hole Plot (FilePrefix =nnode_Dark_05Time=(05))NewCurrentFile=transient_Transient(InitialTime=0FinalTime=3e‐9InitialStep=1MaxStep=1e‐11BiasModelParameter=OpticsOpticalGenerationReadFromFileScalingvalue=(1at01at099e‐91e15at1e‐91e15at199e‐91at2e‐91at299e‐9))CoupledPoissonElectronHole

75

Bibliography

[1] DABMillerldquoRationaleandChallengesforOpticalInterconnectstoElectronicChipsrdquoproceedingsoftheIEEEvol88no6p7282000

[2] DABMillerldquoOpticalInterconnectstoSiliconrdquoIEEEJournalofSelectedTopicsinQuantumElectronicsvol6no6pp1312‐13172000

[3] D A B Miller ldquoPhysical reasons for optical interconnectionrdquo Int JOptoelectronicsvol1681997

[4] LChenKPrestonSManipatruniandMLipsonldquoIntegratedGHzsiliconphotonicinterconnectwithmicrometer‐scalemodulatorsanddetectorsrdquoOpticsExpressvol17no17pp15248‐152562009

[5] SBSamavedamMTCurrieTALangdoandEAFitzgeraldldquoHigh‐qualitygermaniumphotodiodesintegratedonsiliconsubstratesusingoptimizedrelaxedgradedbuffersrdquoAppliedPhysicsLettersvol73no15pp2125‐21271998

[6] MTakenakaKMoriiMSugiyamaYNakanoandSTakagildquoUltralow‐dark‐currentGephotodetectorwithGeO2passivationandgas‐phasedopedjunctionrdquoIEEEInternationalConferenceonpp36‐382011

[7] JEBowersDDaiYKangandMMorseldquoHigh‐gainhigh‐sensitivityresonantGeSiAPDphotodetectorsrdquoProcSPIEvol7660pp1‐82010

[8] SAssefaFXiaandYAVlasovldquoReinventinggermaniumavalanchephotodetectorfornanophotonicon‐chipopticalinterconnectsrdquoNaturevol464no7285pp80‐842010

[9] DANeamenSemiconductorPhysicsandDevicespdf3rdedMcGraw‐Hill2003

[10] NVLoukianovaetalldquoLeakageCurrentModelingofTestStructuresforCharacterizationofDarkCurrentinCMOSImageSensorsrdquoIEEETransactionsonElectronDevicesvol50no1pp77‐832003

76

[11] RWidenhornMMBloukeAWeberARestandEBodegomldquoTemperaturedependenceofdarkcurrentinaCCDrdquoProcSPIEvol4669pp193‐2012002

[12] GEnemanetalldquoImpactofDonorConcentrationElectricFieldandTemperatureEffectsontheLeakageCurrentinGermaniump+nJunctionsrdquoIEEETransactionsonElectronDevicesvol55no9pp2287‐22962008

[13] RNHALLldquoElectron‐HoleRecombinationinGermaniumrdquoPhysicalReviewvol87no2pp387‐3871952

[14] C‐TSahandWShockleyldquoCarrierGenerationandrecombinationinP‐NJunctionsandP‐NJunctionCharacteristicsrdquoproceedingsoftheIREvol1p12281956

[15] LEsakildquoNewPhenomenoninNarrowGermaniump‐nJunctionsrdquoPhysicalReviewvol109no2pp603‐6041958

[16] GAMHurkxandHCDGraaffldquoANewAnalyticalDiodeModelIncludingTunnelingandAvalancheBreakdownrdquoIEEETransactionsonElectronDevicesvol39no9pp2090‐20981992

[17] LChenandMLipsonldquoUltra‐lowcapacitanceandhighspeedgermaniumphotodetectorsonsiliconrdquoOpticsExpressvol17no10pp7901‐79062009

[18] EGaubasMBauzAUleckasandJVanhellemontldquoCarrierlifetimestudiesinGeusingmicrowaveandinfraredlighttechniquesrdquoMaterialsScienceinSemiconductorProcessingvol9pp781‐7872006

[19] ldquoSynopsysIncMountainViewCAC‐200906edSentaurusDeviceReferenceManualrdquo2009

[20] DDaiMJWRodwellJEBowersYKangandMMorseldquoDerivationoftheSmallSignalResponseandEquivalentCircuitModelforaSeparateAbsorptionandMultiplicationLayerAvalanchePhotodetectorrdquoIEEEJournalofSelectedTopicsinQuantumElectronics2009

[21] SAssefaetalldquoCMOS‐IntegratedOpticalReceiversforOn‐ChipInterconnectsrdquoIEEEJournalofSelectedTopicsinQuantumElectronicsvol16no5pp1376‐13852010

[22] RASorefandSMemberldquoSilicon‐BasedOptoelectronicsrdquoproceedingsoftheIEEEvol81no12p16871993

77

78

ii

iii


設計與建模


國立交通大學


碩士論文






September 2012





iv

v


vi

vii

摘要










viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

iii


設計與建模


國立交通大學


碩士論文






September 2012





iv

v


vi

vii

摘要










viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

iv

v


vi

vii

摘要










viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

v


vi

vii

摘要










viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

vi

vii

摘要










viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

vii

摘要










viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

viii

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

ix


Li‐YingWu

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

x

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

xi


摘要 vii

Foreword ix

TableofContents xi


Listoffigures xiii

ListofTables xv



111History 1






212SRHcurrent 7






24Conclusion 19


31TCADModels 21




xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

xii





34Conclusion 33









44Conclusion 44




53Lengtheffect 50





542Eyediagram 53

55Conclusion 55


Appendices 61


Sprocess 63

SdeviceforIV 67

SdeviceforC‐V 70


Bibliography 75

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

xiii


Listoffigures


















xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

xiv



























xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

xv

ListofTables




xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

xvi

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

1



111History


2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

2





3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

3





4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

4

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

5








Eq 2‐1


6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

6

1 Eq 2‐2

Eq 2‐3



7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

7

212SRHcurrent




Uσ σ v pn n N



8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

8


∙ Eq2‐5


9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

9





10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

10


221StructureofGePD



11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

11






12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

12



13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

13





k Ae Eq2‐6

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

14




222 lowast

22 lowast

2 Eq2‐7

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

15


16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

16



17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

17




18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

18


19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

19

24Conclusion


20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

20

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

21




31TCADModels





22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

22





23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

23





24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

24


25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

25




26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

26







27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

27



28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

28


29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

29





30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

30



31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

31


32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

32





33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

33

34Conclusion


34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

34

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

35







36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

36



37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

37




Eq 4‐1


38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

38







39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

39


40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

40





41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

41


42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

42






43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

43




44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

44

44Conclusion



45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

45







46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

46




47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

47





hGe LGe 1μmWi

Eq 5‐1

Fig5‐3(a)

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

48

Fig5‐3(b)





49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

49



50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

50

53Lengtheffect





51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

51





I I ∙ e Eq 5‐2

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

52



53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

53

54Frequencyresponse

541Bitstreaminput



542Eyediagram


54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

54


55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

55

55Conclusion


56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

56

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

57



58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

58



59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

59



wGege3microm

(Wi=18microm)






wGe 34microm

Wi frac12ofwGe






Toboostspeed






60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

60








61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

61

Appendices

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

62

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

63


Sprocess


64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

64


65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

65


66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

66


67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

67

SdeviceforIV


68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

68


69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

69


70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

70

SdeviceforC‐V


71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

71


72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

72

Sdevicefortransient


73


74


75

Bibliography











76













77

78

73


74


75

Bibliography











76













77

78

74


75

Bibliography











76













77

78

75

Bibliography











76













77

78

76













77

78

77

78

78

Documents

國立交通大學 電子物理研究所 碩士論文N germanium photodiodes. To investigate the main physical mechanism behind the dark current of germanium photodiode, analysis of

國立交通大學電子物理研究所碩士論文N germanium photodiodes. To investigate the main physical mechanism behind the dark current of germanium photodiode, analysis of