Vanadium Dioxide Films Deposited on Amorphous SiO2- and Al2O3-Coated Si Substrates by Reactive RF-Magnetron Sputter Deposition

Abstract

VO2 films showing abrupt metal–insulator transition (MIT) were fabricated on amorphous-film-coated Si wafers by reactive RF-magnetron sputter deposition using a V-metal target, and postdeposition annealing. The amorphous films were thermally grown SiO2 or Al2O3 films deposited by low-temperature plasma-enhanced atomic layer deposition. The effects of the underlayer and chamber pressure governing oxidation ambient on MIT characteristics were investigated. The MIT of VO2 films deposited at 5 mTorr on SiO2 and Al2O3 induced resistance changes of 1.3×104 and 2.3×103, respectively. The resistance change due to MIT was larger than 6.3×103 in an operating pressure range as wide as 5–25 mTorr on SiO2.