Low temperature fabrication of vanadium oxide films for uncooled bolometric detectors

Vanadium oxide films with temperature coefficient of resistant of −2.6% K−1 have been fabricated on Si3N4-film-coated Si substrates by ion beam sputtering in a controlled Ar/O2 atmosphere, at a relatively low growth temperature of 200 °C. The as-deposited films show no semiconductor-to-metal phase transitions even heated up to 150 °C. X-ray diffractometry shows that the main compound of the VOx film is a metastable phase of vanadium dioxide (VO2(B)) and the VO2(B) film can be transformed into VO2 film by post-growth annealing at 450 °C in flowing Ar atmosphere.