Sensitivity enhancement analysis of frequency tuned-SAW resonator with temperature for sensor applications

Cooling of quartz-SAW devices leads to a noticeable increase in sensitivity. However, the effect of heating on the output characteristics of quartz-SAW resonators in terms of sensitivity has not yet been studied. Here we examine the inverse parabolic temperature characteristics of a quartz-SAW resonator in order to study the effect of temperature rise on the sensitivity. Various characteristics of a quartz SAW resonator are measured such as frequency shifts, phase, and group delay by Vector Network Analyzer (VNA) over a temperature range of 5 °C to 150 °C. It is shown that the sensitivity could be increased at certain combinations when the operating frequency (fo) is tuned away from the centre frequency (fc) along with temperatures higher or lower than room temperature. Sensitivity increases up to 24-fold was achieved when T > 120 °C and fo > fc. This study of temperature tuning of SAW device will be useful for enhancing the sensitivity in various SAW sensing applications for various industrial purposes.