Peculiarities of SnO2 thin film deposition by spray pyrolysis for gas sensor application

The analysis of the influence of deposition modes on the structure, electrical and gas sensitivity characteristics of SnO2 films, deposited by spray pyrolysis, is presented in this report. X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser ellipsometry were used for this purpose. It was determined that nano-size polycrystalline SnO2 films with thickness >30 nm can have different structure in dependence on pyrolysis temperature and film thickness. Ultra-thin SnO2 films with thickness d<20 nm are discontinuous. The relation between structure of the films and gas sensitivity properties is discussed. The explanation of observed effects was made.