Preparation and characterization of SiO2-MxOy (M = V, Sn, Sb) thin films from silicic acid and metal chlorides

Abstract

The preparation of SiO2-MxOy (M = V, Sn, Sb) binary oxide thin films by sol-gel method was investigated. The reaction of silicic acid with metal chloride (M = Sn and Sb) or oxychloride (M = V) formed homogeneous solutions. The dip-coating of slide glass and silicon wafer followed by heat treatment gave oxide films having Si-O-M bond. The changes of FT-IR spectra as a function of heat treatment temperature and molar composition confirmed the Si-O-M bonds. The sheet resistance of films increased with an increase on heat treatment temperature and decrease in the content of metal oxide MxOy. X-ray diffraction peaks were observed for the SiO2-V2O5 films with high V2O5 contents and heat-treated above 250 degrees C, while the others were amorphous. Oxide films heat treated at 500 degrees C had a thickness between 340-470 nm.