Pressure and temperature determination with micromachined GAN/SI SAW based resonators operating in the GHZ frequency range

This paper describes the experimental development of membrane supported single SAW resonator sensor structures, operating in the 4-12 GHz frequency range. The sensors are manufactured on GaN/Si, using advanced nano-lithographic and micromachining techniques. Rayleigh and Lamb resonance frequency peak shifts vs. pressure and temperature were successfully used for simultaneous determinations of these parameters. Determinations have been performed in the 1-7 Bar pressure range and 20-150°C temperature range. Very high values for the pressure and temperature sensitivities have been obtained, due to the high frequency operation, possible for GaN based SAW type sensors.