K.Azadkish

H. Asadi

M.N.Amiri

S.Amininasab

E.Bahjati

H.Hamidi

A.R.Jafari

M.J.Hosseinishahi Dastjerdi*

X-ray Photoelectron Spectroscopy Instrumental & Application

X-ray Photoelectron Spectroscopy Instrumental & Application

2014/04/06

دستگاهوری و کاربردایکس ی اشعه فوتوالکترون بینی طیف

1393/01/17

K.Azadkish

H. Asadi

M.N.Amiri

S.Amininasab

E.Bahjati

A.R.Jafari

H.Hamidi

M.J.Hosseinishahi Dastjerdi*

آزادکیش کمالاسدی حسین

امیری نبی محمدامینینسب سعید

بهجتی اسماعیلجعفری رضا احمد

حمیدی هادیحسینیشاهی جواد محمد

دستجردی*

Introduction

Instrumental

Application

XPS Comparison with other techniques

Conclusion

1

Introduction

XPS

Received the 1981 Nobel Prize in Physics for his work

K. Siegbahn

Re: Douglas A. Skoog, F James Holler, Stanley R. Crouch/ Principles of Instrumental Analysis / Sixth edition 2

What is XPS?

Introduction

Principles of XPS

Re: www.surfaceanalysis.org 3

Conduction BandConduction Band

Valence BandValence Band

L2,L3L2,L3

L1L1

KK

Fermi LevelFermi Level

Free Electron LevelFree Electron Level

Incident X-rayIncident X-ray

1s1s

2s2s

2p2p

Introduction

Re: Siegbahn, K.; Edvarson, K. I. Al (1956). "β-Ray spectroscopy in the precision range of 1 : 1e6". Nuclear Physics 4

Introduction

Binding energy of the electron

The kinetic energy of the emitted electron

Work function

Re: Siegbahn, K.; Edvarson, K. I. Al (1956). "β-Ray spectroscopy in the precision range of 1 : 1e6". Nuclear Physics 5

Instrumental

6

Instrumental

Re: Douglas A. Skoog, F James Holler, Stanley R. Crouch/ Principles of Instrumental Analysis / Sixth edition

Multichannel transducer

Hemispherical capacitor

Multichannel analyzer

Lens

Out put display

7

Application

8

9Re: Surface Sensitive Technique

XPS Comparison with other techniques

Conclusion

One of the most important applications of XPS has been the identification of oxidation states of elements in inorganic compounds

XPS provides information about not only the atomic composition of a sample but also the structure and oxidation state of the compounds being examined.

XPS is used from starting Li(A>=3) because of smaller orbital’s radius and analysis of organic compounds cannot be done with XPS because of degredation with radiation

10

Conclusion

11

Spectra are a plot of detected electron current (Intensity) vs KE (plotted as BE).

Peaks occur at characteristic BEs.

Narrow scans at high instrumental resolution are often used for – more quantitative estimate of the composition (from peak areas) – Chemical states of the different elements on the surface. – Relative intensity measurements can provide information about the thickness of an over layer.

Survey scan gives information about the elements present; it is a plot of intensity over a wide BEs at low instrumental resolution.