SYNTHESIS OF VANADIUM DIOXIDE THIN-FILMS FROM VANADIUM ALKOXIDES

A very simple sol-gel route to vanadium dioxide thin films is describe d. Vanadium alkoxide molecular precursors are deposited onto a fused s ilica substrate by the spin coating technique. An amorphous thin film is obtained at room temperature which leads to crystalline VO2 when he ated at 450-degrees-C under a reducing atmosphere (Ar-H2). Sol-gel der ived VO2 thin films have a good optical transparency. They exhibit a r eversible semiconductor-metal transition around 70-degrees-C and their conductivity increases by three orders of magnitude when heated above that temperature.