Simple and efficient synthesis of high-quality VO2 thin films and their application in vacuum sensor with wide pressure range

Abstract

High-quality VO2 films have been successfully synthesized on SiO2/Si substrates by a simple and efficient method in a tube furnace. The as-synthesized VO2 films were structurally uniform and single-crystalline. These films show a large resistance change of more than four orders of magnitude with a 5K width of the hysteresis loop as the temperature is cycled through the phase transition. VO2 thin-film devices have been fabricated by reactive ion etching (RIE) and deposition processes. The current response of devices under light illumination and bias exhibited a higher sensitivity and a much wider pressure range than that without light illumination. Experimental data also revealed that the current response of a VO2 film device shows an approximately linear dependence on the logarithm of air pressure. These high-quality VO2 thin films with excellent properties have potentially promising application in vacuum sensor.