X-ray Photoelectronspectrocopy (XPS)
XPS is a surface sensitive (0.5-4nm) technique for the non-destructive analysis of the elemental composition and compound determination of conductive, semiconductive or insulating solids or powders.
XPS utilizes photoionization and analysis of the kinetic energy distribution of the emitted photoelectrons. Therefore XPS can identify and quantify the elemental composition of the surface and determine the oxidation states of the detected elements.
PHI 5000 VersaProbe II equipped with a monochromatic Alkα radiation source.
Scienta HIPP II Lab equipped with a monochromatic Alkα radiation source and reaction cell.
Features of the instrument:
Spectroscopy also as imaging mode
Angle resolved measurements fort he non destructive analysis of buried interfaces or surface contaminations (Angle resolved XPS)
Depth profiling with Ar+ ions (destructive) for the analysis of layered systems (Sputter XPS)
Valenzband spectroscopy with a He source (UPS)
Heating up to 1200°C
Remove surface contaminations by gentle Ar bombardment
Ambient pressure XPS (AP-XPS): process gas e.g. O2, N2, H2O, CO2 up to 25mbar in situ for the study of e.g. oxidation processes
Powders (not for UPS, AP-XPS) as well as solids (substrates, thin layers) are possible. Sample height less than 2cm. The samples must be compatible with UHV conditions and stable with respect to X-rays.
The size of the sample, which should be treated in the reaction cell, is limited to 1cmx1cm and 0.5cm height.