Temperature stability is a critical issue for SAW devices in communication and sensor applications. The negative temperature coefficient of delay (TCD) of SiO2 makes it suitable as a compensation layer in multilayer structures where the piezoelectric layer possesses a positive TCD. In this work, the SAW propagation properties, including velocity dispersion, electro-mechanical coupling coefficients, and propagation attenuation in ZnO/SiO2/Si structures are investigated using the transfer matrix method. For different thickness ratios of ZnO to SiO2, temperature compensation of the second GSAW modes at frequencies in the range of 1GHz to 3 GHz is calculated. The simulation results show good temperature stability at 2.4 GHz when the ZnO:SiO2 thickness ratio is 2:3 and total film thickness is 3 μ m.
All Science Journal Classification (ASJC) codes
- Acoustics and Ultrasonics