High temperature coefficients of resistance of VO 2 films grown by excimer-laser-assisted metal organic deposition process for bolometer application

Abstract

With bolometer application in mind, we prepared VO 2 films on TiO 2 (001) substrates by an excimer-laser-assisted metal organic deposition process at 300 °C or less. A metal-to-insulator transition of VO 2 is expected to induce high temperature coefficient of electrical resistance (TCR) useful for high-performance infrared sensors, but the practical use of crystalline VO 2 films has been prevented due to the accompanied wide hysteresis. In this study, by forming the epitaxial phase only near the substrate interface, the transition of the film was successfully broadened and the hysteresis disappeared. The maximum TCR of the film was more than –10%/°C near room temperature, and the temperature range in which TCR was higher than –4%/°C was very wide (280–320 K).