FORMATION AND THERMOCHROMISM OF VO(2) FILMS DEPOSITED BY RF MAGNETRON SPUTTERING AT LOW SUBSTRATE-TEMPERATURE

Thermochromic VO2 films were deposited on substrates of silicon and Pyrex glass by reactive rf magnetron sputtering and characterized by thin-film X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), atomic force microscopy (AFM) and spectrophotometry. Films with a VO2 single phase were formed above a fairly low temperature of 300-degrees-C by controlling precisely the oxygen flow ratio. The use of a nucleated substrate improved the crystallinity of the VO2 films deposited at low temperature. A negative substrate bias appeared to have an effect of favoring the formation of a VO2 single phase at a substrate temperature as low as 250-degrees-C.