AES study of Pt-doped thin Sn-O-Te films

Thin SnO2-based films with Sn/Te ratio (RSn/Te) ≈ 2.1, prepared by thermal vacuum co-evaporation of Sn and TeO2 and doped with Pt before or after thermal annealing, are studied by Auger electron spectroscopy (AES). Thermal annealing leads to changes in the chemical composition and structure (crystallization) of the amorphous as-deposited films. The depth profiling has revealed that the film composition is homogeneous and Pt is dispersed throughout the whole volume of the samples irrespective of their structure and the sequence of doping and thermal annealing. Information is obtained about the oxidation processes taking place during the preparation and thermal annealing of the films, about the influence of the substrate material and the correctness of the evaporation process modeling. It is shown that the significantly higher ethanol sensitivity of the films doped with Pt before annealing is not related to the Pt-distribution.