Sharp semiconductor-to-metal transition of VO₂ thin films on glass substrates

Outstanding phase transition properties of vanadium dioxide (VO ₂) thin films on amorphous glass were achieved and compared with the ones grown on c-cut sapphire and Si (111) substrates, all by pulsed laser deposition. The films on glass substrate exhibit a sharp semiconductor-to-metal transition (∼4.3 °C) at a near bulk transition temperature of ∼68.4 °C with an electrical resistance change as high as 3.2 × 10 ³ times. The excellent phase transition properties of the films on glass substrate are correlated with the large grain size and low defects density achieved. The phase transition properties of VO₂ films on c-cut sapphire and Si (111) substrates were found to be limited by the high defect density.