Phase transition VO2 thin films for optical switches

This paper presents a method to make vanadium dioxide (VO2) crystallites on silicon substrates by reactive ion beam sputtering. The thickness of the thin film is about 100nm. The phase transition temperature Of VO2 is 65degreesC. The transmittance of the semiconducting phase VO2 is about 50% and it is reduced to as low as 3% in metal phase at the infrared wavelength spectrum. The extinction ratio of the optical switches is 12dB.and the insertion loss is of 1-2dB. The switching time is about 1 ms.