Specialist : Dr. Burcu Selen ÇAĞLAYAN

Phone : +90 212 359 68 56, 359 48 06
Fax : +90 212 358 27 24
E-mail : selenbur@boun.edu.tr


X-ray photoelectron spectroscopy (XPS) is a quantitative analysis technique of the surface composition, which is capable of providing atomic and molecular information regarding the surface of the material. It is used to examine core-levels and subsequently to study the composition and electrostatic states of the surface region of a sample by energy-disperse analysis of the emitted core photoelectrons.


Using XPS, some important questions can be answered.

·         Which elements are present at the surface?

·         What chemical states of these elements are present?

·         How much of each chemical state of each element is present?

·         What is the spatial distribution of the materials in three dimensions?

·         If material is present as a thin film at the surface,

o   How thick is the film?

o   How uniform is the thickness?

o   How uniform is the chemical composition of the film?


XPS is used widely in all branches of pure and applied sciences- as well as for troubleshooting and quality assurance purposes- but some main headings are given here.

·         Microanalysis of the surfaces of metals and alloys

·         Study of mineral surfaces

·         Study of polymers

·         Study of materials used for medical purpose

·         Surface study of cements and concretes

·         Study of basic atomic physics


In our laboratory at Bogazici University Advanced Technologies R&D Center, Thermo Scientific K-Alpha X-ray Photoelectron Spectrometer is used.


Key Features

·         Analyzer

o   180° double focusing hemispherical analyzer

o   128-channel detector

·         X-ray source

o   Al Kα micro-focused monochromator

o   Variable spot size (30-400µm in 5µm steps)

·         Ion Gun

o   Energy range 100-4000eV

·         Charge Compensation

o   Dual beam source

o   Ultra-low energy electron beam

·         Sample Handling

o   4-axis Sample Stage

o   60 x 60mm sample area

o   20mm maximum sample thickness

·         Vacuum System

o   2x 260 l/s turbo molecular pumps for entry & analysis chambers

o   Auto-firing, 3 filament TSP

·         Data system

o   Avantage data system

o   Processing license

o   PC



K-Alpha XPS Analysis from Research to Routine

·         High Performance Spectroscopy

o   Source-defined analysis area from 30-400 μm

o   5 μm step size ensures that the analysis area closely matches the feature to be analyzed

o   Rapid survey spectrum acquisition

o   Excellent energy resolution for chemical state determination

·         Chemical State Imaging XPS

o   Spectral Imaging

o   Rapid 128 channel snapshot spectra

o   Entire sample stage area imaging

o   Overlay XPS data with automatically collected optical images

·         Insulator Analysis

o   Insulating samples are easily analyzed using state-of-the-art charge compensation

o   Simple one-click turnkey operation

·         Depth Profiling

o   Ion gun provides high current density even at low beam energy

o   Azimuthal and Comp-eucentric rotation

o   Full computer control of the ion gun and gas handling for excellent reproducibility

o   Automatic alignment of source



AvantageTM Data System

The AvantageTM data system incorporates a comprehensive suite of software for:

• Total instrument control

• Data acquisition

o   Spectra

o   Images

o   Profiles

o   Linescans

• Data interpretation

o   Auto elemental and chemical state ID

• Data processing

o   Quantification, peak fitting, real-time profile display, spectrum-image manipulation

• Advanced processing

o   PCA, Phase analysis, TFA, NLLSF, PSF removal

o   Optical/XPS image overlays

• Report generation

• Vacuum system and sample handling