Dynamic response of VO2 mesa based GaN microcantilevers for sensing applications

For the first time, dynamic response of GaN microcantilevers with integrated piezoresistive VO ₂ mesa, as high sensitive deflection transducers have been investigated. The studies are carried out by a direct excitation method using a piezo-chip attached to the bottom of the microcantilever structure, highlighting the utility of these cantilevers as deflection transducers. The VO ₂ phase was able to detect acoustic waves generated in the Si substrate at resonant frequency with very high sensitivity. A high quality factor of 9400 is recorded at 88 μtorr by these microcantilevers, with an atmospheric quality factor value of 90. The deflection sensitivity is found maximum at the VO ₂ insulator to metal transition temperature (MIT) temperature.