DFT for Effective Mobile DRAM Test

20th of Oct , 2015강 의 정

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1. ICT trends for mobile device

2. Test Challenges -. Restrictions of mobile DRAM test-. DFT for mobile DRAM test

3. Summary

Contents

ICT Trends for Mobile Device

03

4 / 43

ICT Trends for Mobile Device

Mobile Platform : ExtensionSmartphone : Convergence

Automotive

Wearable

Digital Appliance

More Smart DevicesInternet

Camera

Wi-fi

Game

Music

Computer

5 / 43

Global Tablet ShipmentsGlobal Smartphone Shipments

Source : Carnegie Research, IDC 2015 Source : Carnegie Research, IDC 2015

Mobile Era

Global Smartphone, Tablet devices growth rate get decreasedSpecially, Smartphone Market reached a saturation in China

6 / 43

Post Mobile Era - IoT & IoE

Source : Cisco 2014

Connected Device Market Explosion by IoT BoomingWearable/Smart Car leads the Growth

(unit : billion)

Y2003 Y2008 Y2010 Y2015 Y2020

50

40

30

20

10

07.6B

Cross-over

Devices > world population

Smart Things

50B

World Population

<Connected Devices per Person>

vs.0.08 in 2003 6.58 in 2020

Connected Devices Internet of Everythings

7 / 43

Mobile DRAM Usage goes beyond Mobile

LPDDR4

Network

Automotive

Set top box

Micro Server

Tablet PC

UltrabookIoT

LPDDR3

Smartphone

Ultrabook

Tablet PC

Tablet Smartphone

LPDDR2

LPDDR1

Feature phone(Media phone)

Higher Power Efficiencyin a small form factor

Smartphone

Wearable

8 / 43

Wearable Devices Market Forecast

Computing performance

Mem

ory

Den

sity

Smart Glassw/ High Density mDRAM/Flash

Feature-rich Smart Watchw/ Mid/Low Density mDRAM/Flash

Basic Smart Watchw/ Less or Small Density of mDRAM/Flash

Wrist band

Hardware Landscape of Wearable DevicesWearable Devices Shipments

Wrist wear applications will lead Wearable Devices Market (CAGR 42.6%)From Smart Glass to High Density Devices

Source : IDC 2015

(M unit)

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Wearable Device Evolution

Wearable devices will evolve portable → attachable → eatable devices

Portable Attachable Eatable / Implementable

Now ~ 2020 2020 ~

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Wearable Device Status

New Wearable Company market advanceNew Platform leadership competition will be deepen

‘15 4월i-watch

G watch Urbane LTE

‘14 9월

Gear S Gear VR

Smart watch 3

ZENwatch

‘14 6월

G watch

Moto360

Android Wear IoT NotificationGoogle Fit

Nest 기반 Smart Home Platform

Galaxy Gear1

CES ‘14 1월 MWC ‘14 2월

Pebble Steel & App store 공개

Life Band Touch

Smart Band, Core

TomTom社, Nike+ 브랜드 없는 GPS 손목시계

자동차와 wearable 연동

Gear 2 & Fit

Talk band

Smart Gloves

Lumus Glasses

‘14 10월

새로운Platform 전쟁

MWC ‘15 2월

Huawei watch

다양한 OS 소개

OS

11 / 43

Smart Watch Role

Smart watch는 단순 시계가 아닌 IoT의 중심(Control Device) 역할 예상

<iWatch>

iCloud

iPodiCar

Mac

iPad

iPhone

iTV

iHome

Medical

Message

Phone

Sports & Fitness

Smartwatch

Music

Driving DivergenceSmart Watch Role

12 / 43

Augmented / Virtual reality Market will expand from 2016Augmented reality will be majority and merge rapidly with whole industry

Augmented / Virtual Reality Market

Source: Digi Capital 2015

Unit:M$

Virtual reality applicationsAugmented / Virtual reality revenue

적용 분야 예시

엔터테인먼트 • 3D 게임, 여행 같은 체험 형 콘텐츠

교육용• 박물관 체험, 천체위치 연구, 건축 설계나 화학분자 설계연구, 군사용 비행, 전투모의 훈련

의료용• 가상 수술, 원격진료, 해부학 등 입체영상 응용, 각종 공황장애와 트라우마 치료

산업용• 제품 가상 체험 형 마케팅, 로봇 원격조종을 통한 제조 공정 활용

You Visit of New York ROOM VR

Oculus Rift 수술상황체험Oculus Rift 전차운행훈련

(B$ unit)

13 / 43

Google Magic Leap

Magic Leap will lead Post Smart Phone era.Selected MIT breakthrough technologies 2015

ProjectorProjector of Google Glass

Magic Leap’s 3D image

Magic Leap의 OST-HMD의 구조는 Projector로 착용자의눈동자에 이미지를 주사하고 적외선 광원을 비춘 후 적외선

카메라로 사용자의 동공을 tracking. Machine vision camera, 머리 동작 센서, 센서 어셈블리를 통해 자이로 센서와가속도 센서 Data를 수집해 사용자의 동작과 속도에 맞게 실제세계 이미지에 2D나 3D 증강현실 객체를 구현하는 형태로 실제

환경을 그대로 구현한 가상 현실에서 게임을 즐기거나 실제환경에 가상 아바타를 구현한 혼합 현실을 경험

Magic Leap OST-HMD system

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Consumer application will need High performance / Low power memory

LPDDR4의 응용 분야 확대 Device별 응용분야 확대

PC

Notebook

DTV/ STB

Automotive

ARM-server

Tablet

S/P

DDR3/4

LPDDR4

WIO2?

Mobile

Consumer

PC

SV

Client

Automotive/ Network

ARM-Server

LPDDR4(SP/Tablet)

ARM-Server DTV Auto. STB Network

I/O Config X64(/x72) x64 x64 x64 x16

MemorySolution

DDR3/4LPDDR4

DDR3/4LPDDR4

DDR3/4LPDDR4

DDR3/4GDDR5LPDDR4

DDR3/4LPDDR4

Expansion of mobile DRAM

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Mobile Platform Extension to Automotive

Automotive is more than just “Thing” and is becoming smarter !- More Data, More Devices, and More Services

STEP 2 : Infotainment

STEP 3 : Smart car, Automotive IoT

STEP 1 : Navigation

(driver-less)

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Smart Home Market

Smart home market will be twice after 5YOver 12% of WW house hold will possess in 2019

WW Smart home market

Source : Strategy Analytics 2014/2015, 한국 스마트홈 산업 협회

‘14 ‘15 ‘16 ‘17 ‘18 ‘19

단위: 억달러

480575

690821

1,0001,115

13%

25%38%

8%

18%27%

4%

8%12%

‘13 ‘16 ‘19

미국

영국

글로벌

시장

규모

보급률

주요 업체별 사업동향

기업 활동내용

Google- 온도 조절장치와 화재 경보장치 관련 ‘Nest Labs’ 인수- CCTV 제조사 ‘드롭캠(Dropcam)’, 스마트홈 네트워킹기술 개발사인 ‘Revolv’ 인수

Apple- iOS 기반 스마트홈 개발도구인 ‘Home Kit’ 공개- 애플 협력업체들은 홈킷을 통해 스마트제품 및 서비스를 개발/출시 가능

Microsoft- 클라우드 기반 Smart Home 사업 확대- PC 운영체제 + Smart TV 운영체제 ‘Media Room’ 공개- Xbox와 콘솔 게임기의 강점을 이용한 영향력 강화시도

삼성- 자체 개발한 ‘타이젠 OS’ 를 탑제한 Smart TV중심으로냉장고,세탁기 등을 연동한 스마트홈 구축에 주력

- 미국 사물인터넷 업체인 ‘Smart Things’ 인수

LG

- Platform 호환성 강화를 통해 스마트홈 Ecosystem 구축

- Smart Home 서비스인 ‘Home chat’을 통한 스마트폰연계 가전기기 제어서비스 강화 계획

Amazon- 음성기반 개인비서 서비스 ‘Alexa’ 공개, 추후 플랫폼으로 진화 시킬 계획

Mobile DRAM Trend

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Mobile Market Outlook

Mobile DRAM design is steadily evolving for better power efficiency and wider data bandwidth

Mid/low-end will lead smartphone market growth

Source: SK hynix Marketing

(Units in Millions)

Source: iSuppli 2014

703

990

1,200 1,338

1,472 1,590

1,685

58%

66%69% 71% 72% 74% 75%

0%

10%

20%

30%

40%

50%

60%

70%

80%

0

200

400

600

800

1,000

1,200

1,400

1,600

1,800

2,000

2012 2013 2014 2015 2016 2017 2018

High-end (>$300) Mid-end ($100-300) Low-end (<$100)

Low/Mid portion (%)

0%

0%

0%

0%

0%

0%0%

0%0%

0%

0%0% 16%

27%

18%

11%

3%0% 0%

0%

0%

0%

0%

0%

0%0%

0%0%

0%

0%0%

0%

3%

17%26%

16%

9%5%

0%

0%

0%

0%

0%

0%0%

0%0%

0%

0%0%

0%

0%0%

3%

24%

34%37%

0% 0%

0%0% 0% 2%

22%

57%

72%67%

58% 54% 41%

23%

10%

7%

0% 0%

0%0% 0% 0% 0% 0% 0% 0% 0%

2%10%

26%

40%46%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

2000200120022003200420052006200720082009201020112012201320142015201620172018

LPDDR2

DDR3

DDR4

DDR2DDR

Graphics

SDR

LPSDR/DDR

LPDDR3

LPDDR4

WIO

Mobile DRAM Demand Portion Smartphone Market Outlook

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Mobile OS Evolution

4GB Memory required for Flagship smartphone from Android MMinimum density increasing

Kitkat Lollipop Android M Android NJellyBeanICSAndroidVersion

1GB

2GB

3GB

4GB

340MB

512MB

832MB

1GB

lagship

inimum Density

F

M

2GB

4GB?

1GB?

340MB

LPDDR2 LPDDR2

LPDDR3

LPDDR3

LPDDR4 LPDDR4

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Mobile DRAM Roadmap

2013 20202014 2015 2016 2017 2018 2019

BW [GB/s]

15.0 LPDDR3 (1866)

25.6 LPDDR4 (3200)

30.0 LPDDR4 (3733)

34.1 LPDDR4 (4266)

51.2 LPDDR5 (6400)

12.8 LPDDR3 (1600)

Uncertain

WIO2?

LPDDR5에 대한 요구는 2018년 이전에는 일부 고객들로 제한적하지만 Specification 논의는 빠른 속도로 진행 예상

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LPDDR Memory Evolution

In recent years, memory BW becomes doubled at every 2 yearsPower efficiency improved at similar rates

LPDDR3 LPDDR4 ?

mW/ GBps GB/ s

2002 2006 2010 2012 2015 ?

LPSDR LPDDR

LPDDR2

Year

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10:083

Density & Performance

Wearable - Key Requirements

Hi g h

L ow er Power Consumption

C urvedForm Factor

22

For Hub function(High resolution N-screen)

High density/

High performance

Battery Constraint

Package SizeHeight (thinness)Flexible package

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LPDDR4X (Jedec standard)

VDD2 1.1V + VDDQ 0.6VLPDDR4X

LPDDR4VDD2 = VDDQ (1.1V)

That every customer concerned with SoC needs power

LPDDR4X will be solution of power efficient device

LPDDR4 LPDDR4X

Interface

Type LVSTL LVSTL extension

고려 사항 Reference VDD2 / VDDQ 분리

Tx Rx

Rx

1.1V

1.1V Tx Rx

Rx

1.1V

0.6V

Power

Bandwidth

Bus Utilization

PKG

SI/PI

[ What’s in industry players’ mind? ]

Restrictions of Mobile DRAM Test

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Cost

Mobile [LPDDR3, LPDDR4] Computing [DDR3, DDR4]

Wafer Test PKG Test Wafer Test PKG Test

I/O X32, X64 X4, X8, X16

Ball Type134B,168B,216B,220B,256B,253B,261B,361B,396B,426B,456B,504B,366B,450B,272B,200B,

480B78F, 96F

Pitch 0.35Pitch 0.8Pitch

Speed Max 4.2Gbps Max 3.2Gbps

33%

67%

15%

85%

Mobile vs. Computing DRAM

Mobile DRAM is required various ball types, fine pitch, high speed

and many I/O more than computing DRAM.

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0.2 Pitch는 PKT Infra 개발이 필요하며 투자비 크게 증가 Issue

Package Test 비중을 줄이고 Wafer Test 위주로 진행 필요

Test Infra 개발 필요 현재의 PKT Infra 기술수준으로 대응

Ball Pitch에 따른 Issue

Cost

0.2 Pitch Cost Increment

Sorter 및 Handler 정밀도 향상을 위한 장비 개발 필요

Socket, DSA, BIB 개발 필요

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PoP Warpage Issue

Top과 Bottom Package의 Warpage 거동을 맞추는 게 무엇보다 중요Package Burn in 이후에 변형으로 Warpage guide line 맞추기 어려움

Merits Demerit

- Save space on mother board

- Shorten the length of the trace

→ Signal Character is better

Warpage

TOPBOTTOM

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Known Good Die Test

Over 1.6Ghz to 2.2Ghz speed test is possible at Wafer Tester ? But Parallelism is Too small !!!

Many I/O’s : New challenge uBump probe

APL0778+4Gb LPD3 KGD

PCB

APDRAM

KGD

More Small Form-factor

Solution

ePoP

KGD

Small Form-factor for KGD Solution

• KGD Biz Growing : Aggressive Wafer level test at-Speed

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Test Cost Issue

Test Cost Reduction 위한 Design for Test 기술 개발이 필요

- Data Compress 방법 등 Test Time Reduction 대응

- Pin Reduction을 통한 Wafer test 1 Touch Down 대응

Net die growth according to tech shrink Test COM portion

High density product demand increase with ICT trend1 Die TEST Cost up : Density / Net Die growth

DFT for Mobile DRAM Test

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Package Speed Test - Parallelism

I/O [X]

Device

DQ Non-Shared DQ Shared

DQ [X]

I/O [X/2]

Device

DQ[X/2]

DQ[X/2]

I/O [X/4]

DeviceDQ

[X/4]

DQ[X/4]

DQ[X/4]

DQ[X/4]

DQ Shared + DFT

I/O [X/4]

DeviceDQ

[X/4]

DQ[X/4]

DQ[X/4]

DQ[X/4]

[DFT]Mode

Control

DQ-Shared를 통한 Parallel 확장으로 생산성 향상 DFT (IO Reduction Mode) 적용을 통하여Control 해야 되는 DQ수를 반으로 줄임

> 2DQ-Shared 특성을 유지하며4DQ-Shared의 생산성을 확보

Non-Shared Concept

> 4DQ-Shared로 인한 특성저하로 불가한 Concept

> Non-Shared 대비 특성은저하되지 않으나 생산성이떨어짐

▶ Non-Shared 대비 생산성 2배

▶ Non-Shared 대비 생산성 4배

Package Speed Test 비용 감소를 위해 Parallelism 확장 필요

Mobile DRAM은 IO수가 많아서 Parallelism 확장에 어려움

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Advanced Wafer Burn In Stress

Package Burn In Wafer Burn In Dynamic Wafer B/I

W/L enable 1 100000 100

Stress Dynamic Static Dynamic

S/A 동작 O X O

VPP 전원 내부 외부 ←

Time Long Short ←

Parallelism 10000 1000 ←

Warpage Issue Free ←

Fine ball pitch, Various ball types에 의한 Package Burn In 비용 증가, Warpage issue 및 KGD Biz. 대응

-. 일부 C/A Pin으로 Dynamic Wafer Burn In 구현 가능하도록 DFT 반영 필요

-. Multi W/L Enable을 통한 stress time 감소 필요

-. Stress time 감소로 Sub Wordline Driver, Sense Amplifier Tr.도 Stress 감소

→ Gate to Source/Drain 간 잠재 불량 모델링에 의한 Stress 가속 방법 고려 필요

AdvancedWafer

B/I

WaferB/I

(Static)

PKGB/I

(Dynamic)

① SWD ②S/A

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Wafer Test Cost Reduction

LPDDR4X LPDDR4 LPDDR3

External Power(PPS)

VDD1 1.80 1.80 1.80

VDD2 1.10 1.10 1.20

VDDCA - - 1.20

VDDQ 0.6 1.10 1.20

Level 종류 3 2 2

IO(X32기준)

DQ 32 32

DQS 8 8

DMI 4 -

Total 44 44 40

Pin Reduction을 위한 DFT 발굴

Chuck 무게 한계 극복

Pin 배치 난이도 증가에 따른 P/Card 제약

New Feature 지원 Pin 과 Power 세분화로

Test 용 Pin 증가로 Test Infra Para 한계

4, 8,16개 IO Compress를 통한 IO Pin Reduction

LPDDR4X VDDQ Power를 Internal로 대체

Case A Case B

Pin 수 60Pin 35Pin

Chuck하중

60Pin * 4g * 2000Die 35Pin * 4g * 2000Die

480kg 280kg

Pin 배치

Mobile DRAM은 Wafer test 위주로 진행 필요 → 장비 소요 증가

Multi W/L Activation을 통한 Data Compress

One T/D을 위한 Pin Reduction을 위한 DFT 발굴 필요

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CLK 1Ghz [2Gbps] Operation

High Speed 4Gbps Operation

CMD GeneratorADD Generator→ 내부 Clock

Rising에 동기화

BIST Operation in Wafer Test

External Clock 1Ghz 필요

Command Generator

→ AC Parameter 간격 Setting 가능

Address Generator

→ XMARCH, YMARCH, RMW 등 Address Generator 주행 가능

BIST’s advantage in wafer test

Probe card interface’s max speed is 2Gbps

→ BIST is available to test high speed at low speed tester

Wafer High Speed Test - BIST

BIST Operation in Wafer Test

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Summary

ICT Trends for Mobile Device-. Smartphone, Tablet devices growth rate get decreased-. Wearables, Automotives, Smart home will lead post mobile Era

Restrictions of Mobile DRAM Test-. Package ball type, size, fine pitch & warpage etc-. Wafer level test at-Speed & uBump probe-. Test cost increasing

DFT for Mobile DRAM test-. Advanced wafer burn-in stress-. Wafer test 1-T/D solution -. High speed test Technology-. Many IO’s test about IO DFx

Thank You