Cathodoluminescence emission study of nanostructured SnO2 films deposited by spray pyrolysis

Abstract

In this paper the results of cathodoluminescence (CL) emission study of undoped and doped SnO2 films are discussed. SnO2 films were deposited by spray pyrolysis method. It was shown that the study of CL emission is effective method for structural characterization of metal oxides aimed to gas sensor applications. It was concluded that the changes taking place in CL spectra are connected with the change of both the grain size and the crystallinity (stoichiometry) of the surface layer and the bulk of SnO2. The shape of CL spectra depends on correlation between well-crystallized core and disordered surface layer. It was found that doping is accompanied by deterioration of film crystallinity and the growth of concentration of structural defects responsible for unradiative recombination of excited electrons and holes.