Structural and optical properties of vanadium oxides prepared by microwave-assisted reactive magnetron sputtering

In this work, structural and optical properties of vanadium oxides have been presented. Thin films were manufactured by microwave-assisted magnetron sputtering process. Particles were sputtered from a vanadium target in Ar/O(2) atmosphere. Oxygen partial pressure was changing from 3 x10(-4) to 7x10(-4) Torr. After the deposition, the thin films were additionally annealed at 400 degrees C in ambient air in order to oxidize the films. Structural investigation was performed with the aid of X-ray diffraction measurements and Raman spectroscopy. The results obtained from both methods have revealed that as-deposited films were amorphous, while annealed films had V(2)O(5) crystal form. Optical properties were determined by transmission measurements in the spectral range from 250 to 2500 nm. As-deposited films had low transmission (below 10%), but oxidization by additional annealing of the structure resulted in the increase of the transmission level up to about 20 and 43% at 650 nm wavelength for samples prepared under 3x10(-4) and 7x10(-4) Torr oxygen partial pressure, respectively. The analysis of the structure and optical properties of the thin films has revealed the influence of deposition parameters on the properties of vanadium oxides.