Composition of Amorphous Tin Oxide Films and Their Thermal Behavior

Abstract

Five kinds of amorphous tin oxide films were prepared by reactive evaporation under various conditions. The composition and thermal behavior of the films were studied, by TG, DSC, X-ray diffraction and ¹¹⁹Sn Mssbauer measurements. Depending on the deposition condition, the films had some composition in the range of SnO_1.3-SnO_1.5. The microstructure of the films was porous, this porosity decreased at higher deposition temperatures. When films were heated in air, they were perfectly oxidized at about 200°C, and then crystallized to ruffle-type SnO₂ at about 370°C. In the N₂ gas, films were crystallized to two phases of α-SnO and rutile-type SnO₂ at about 400°C.