Effect of O2 concentration on metal–insulator transition properties of vanadium oxide thin films prepared by radio frequency magnetron sputtering

The influence of O2 concentration on metal–insulator transition (MIT) of vanadium oxide (VOx) thin films was studied in terms of structural and electrical properties. The VOx films were prepared by varying O2 concentration using reactive radio frequency magnetron sputtering with a vanadium target. As the O2 concentration in O2/Ar gas increased from 1% to 7%, the deposition rate of VOx films abruptly decreased and the crystalline phases of the films were transformed from V2O3 to V2O5. The VOx films deposited at 2% O2 mainly consisted of the VO2 phase and showed better crystallinity than those deposited at other O2 concentrations. From the current–voltage measurements of Pt/VOx/Pt capacitors, the VOx films deposited at 2% O2 showed excellent MIT properties which can be applied to memory devices.