Electric Field Induced Metal-Insulator Transition of Vanadium Dioxide Films on Sapphire Substrate Prepared by Inductively Coupled Plasma-Assisted Sputtering

摘要

Single phase monoclinie vanadium dioxide (VOn) Films were successfully grown on sapphire (001) substrate by means of an inductively coupled plasma (ICP)-assisted sputtering with an internal coil. In x-ray diffraction patterns, we observed reflections originating from monoclinie VO: with a main peak at 2θ = 39.77° corresponding to VO2 (020) for films on sapphire (001) substrates. The VO2 films exhibited metal-insulater transition (MIT) at temperatures around 65℃ with three orders of change in resistivity. A simple device of VO2 film on sapphire (001) substrate having aluminum electrodes as ohmic contacts with gap separation of 1.0 mm showed current jump at an applied voltage of 48 V. The current jumped from 7 mA to 200 mA which was a limited value of voltage source.