X-ray Photoelectron Spectroscopy
The XPS platform performs elemental and functional chemical analysis of the extreme surface (a few nanometers) of all types of materials.
Leader
Philippe Fioux and Samar Garreau
Contacts : philippe.fioux@uha.fr or samar.garreau@uha.fr
Description
Areas of activity :
X-ray induced photoelectron spectroscopy (XPS) is a powerful tool for characterising the extreme surface of any solid material (depth analysed between 3 and 9 nm).
The application domains are almost unlimited and XPS analysis is able to :
- identify all the elements (except H and He) and to determine their atomic concentration (limit detection 0.5 %).
- determine the nature of the bonds, the local environment and/or the degree of oxidation of most elements.
- highlight superficial segregations (angular analysis and/or ionic etching).
The analyses are carried out with the SES-2002 photoelectron spectrometer (VG SCIENTA) using monochromatic X-ray radiation and equipped with an electron gun for the analysis of the insulating samples.
Main equipment (strengths of the Institute) :
The platform equipment is as follows :
- Spectrometer XPS SES-2002 (VG SCIENTA) powerful (energy resolution : 0.4eV).
- A Central Satellite interconnects several modules under Ultra High Vacuum (UHV), namely : the XPS spectrometer, a preparation chamber, a metallisation chamber, an introduction chamber and an introduction and storage chamber.
- The preparation chamber is equipped with an ion gun (ionic Ar+ scraping), a mass spectrometer (residual gas analysis), a gas introduction system (Ar, O2, N2).
- 1 Heated sample holder (up to 900°C) for “in-situ” heat treatments under UHV or in a controlled atmosphere.
- 1 Transport case (under UHV) that fits to the introduction chamber It allows the transfer of sensitive samples, prepared in the glove box, for XPS analysis without subsequent contact with the ambient atmosphere.
Technical description
Possible XPS analyses :
➀ : Rapid XPS (overflight spectrum)
➁ : Classic XPS (overflight spectrum + high definition spectra)
➂ : ARXPS (variable angle XPS analysis)
➃ : Line-scan XPS
➄ : Bias-voltage XPS
Possible “in-situ” treatments :
Ⓐ : Argon ionic erosion
Ⓑ : Heat treatment (up to 900°C)
XPS VG SCIENTA Model SES-2002 Spectrometer
Location | rue Jean Starcky |
Spectrometer specifications | Monochromatic RX source (Al Kα = 1486.6 eV) : VG Scienta SAX100 (RX source) VG Scienta XM780 (monochromator) Hemispheric analyser (radius = 200mm) Operation under Ultra High Vacuum (UHV) of the order of 10-9 at 10-10 mbar MCP detector equipped with phosphor screen + CCD camera (imaging) Resolution : 0.4 eV (Fermi level) VG Scienta FG300 electron gun (Flood Gun) for non-conductive sample analysis. |
Detection | All elements from Z = 3 (except H, He) with concentration > 0.5 % |
Depth analysed | 3 to 9 nm (surface analysis) |
Analytical possibilities | ➀,➁,➂,➃,➄ / Ⓐ,Ⓑ |
Constraints/samples | Dimensions (L x W) between 6x4mm and 30x30mm. Surface analysis sensitive to contamination (do not touch with bare hands, atmospheric pollution…) |
Self-service accessibility | No |
Data exploitation | by the manager or the applicant after training in the XPS Spectrum Processing Software : “CasaXPS”. |
Contact : Philippe Fioux, Samar Garreau, Arnaud Ponche