Abstract：Surface acoustic wave (SAW) devices are widely used in radar, communication and daily consumption due to their excellent performance. However, as operating frequency of the SAW devices grows higher and higher, the influence of temperature variation on frequency stability becomes more serious. Thus it is crucial to study the frequency-temperature behavior of SAW devices and improve frequency stability of SAW devices under variable temperature condition. In this paper, the incremental Lagrange equations are used to analyze the frequency shift of SAW affected by temperature. The temperature coefficient of frequency (TCF) is usually regarded as an evaluation on temperature-frequency behavior. To reduce temperature coefficient of frequency, a two-layer SAW resonator model is proposed with a temperature compensation layer. After optimization, the TCF of the SAW resonator with LiNbO3-AlN structure approaches to 0 ppm/℃ at 25℃ (reference temperature). The resonance frequency of the SAW resonator is 1214.9MHz and the wavelength is 4μm.
2020, Vol. 41 
