SI LVV AUGER LINESHAPE ANALYSIS TO STUDY THE OXYGEN-CHEMISORPTION ON TASI2 THIN-FILM

The Si LVV Auger lineshapes of the single-crystal Si(100) surface and the oxygen chemisorbed and clean TaSi2 surfaces are studied by observi ng the three Auger transitions that have different final states in the valence band. It is seen from the Si and Ta Auger fingerprints that b oth Si and Ta form oxides due to chemisorption of oxygen on the silici de surface at room temperature. The variations in the Si LVV fingerpri nt in silicide and the oxygen-exposed silicide are explained in terms of surface effects and the behaviour of the 3s orbital in the bondings involved. Electron energy-loss spectroscopy is used to understand the different shallow-level transitions in Ta and the silicide. The elect ron impact autoionization spectra for TaSi2 and oxygen-exposed TaSi2 a re also presented and analysed, along with the Ta NNN fingerprint to s how the oxidation in Ta.