Research On Preparation Of Vanadium Oxide Thin Film By Magnetron Sputtering

VO₂ film undergoes a semiconductor to metal phase transition at approximately 68℃and the associated great changes in optical,electric and magnetic properties before and after the transition make it possible to make use of this film in smart windows,laser protection and so on. However, vanadium can form dozens of vanadium oxides with oxygen. So preparation of VO₂ thin films with one method is difficult. So preparation of VO₂ thin film with suitable method is very important.In this paper radio frequency reactive magnetron sputtering is used to make V₂O₅ and than followed by vacuum heat treatment which designed by myself to prepare VO₂ thin film. The films are analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscopy. In this paper, impact of magnetron sputtering process parameters (oxygen partial pressure, power and work pressure) and vacuum heat treatment process parameters (heat treatment temperature and time) on preparation of film are system discussed.High purity, density, surface finish V₂O₅ thin film has been made by radio frequency reactive magnetron sputtering. The crystallization state of film changes at different oxygen partial pressures. Increasing power and pressure is good to crystallize and form crystalline V₂O₅ films. Vanadium oxide film with a high level of VO₂ has been prepared by following vacuum heat treatment. Studies have shown that different vanadium oxide phases are obtained by different methods of vacuum heat treatment. VO₂ (B) is obtained under absolute vacuum which has not phase transition property, while under relative vacuum, with the heat treatment temperature increasing (390⁶80℃) vanadium oxide film translate at V₂O₅-V₆O₁₃- VO₂(R)-V₆O₁₃-V₂O₅ into sequence. Heat treatment time also affects phase transformation of magnetron sputtering V₂O₅ thin film. The role of time is similar to temperature but smaller than it. The surface morphology of film before and after heat treatment is different. The surface morphology before heat treatment is shaped as tower as a rule and the surface finish and surface dense are high. There is no defect in the surface. The surface morphology after heat treatment is shaped as rod-shaped and spherical for the film form new vanadium-oxide nucleus and than grows up during heat treatment process.