The embodiment of the invention discloses a
surface acoustic wave resonator and a filter. The
resonator comprises a supporting layer, an energy trap layer, a temperature compensation layer, a piezoelectric layer and an
interdigital transducer layer which are sequentially stacked, the
interdigital transducer layer comprises a plurality of interdigital transducers, the material of the piezoelectric layer comprises X-40Y
lithium niobate, the acoustic bulk
wave propagation velocity of the support layer is greater than the acoustic
surface wave propagation velocity of the piezoelectric layer, and the energy trap layer is used for capturing parasitic charges on the surface of the support layer to improve the Q value of the acoustic
surface wave resonator. According to the embodiment of the invention, the piezoelectric layer and the supporting layer of the resonator are improved, and the speed of transmitting sound
waves by X-40Y
lithium niobate is relatively high, so that the working frequency of the resonator is greatly improved and reaches 5G and more than 5G; the acoustic bulk
wave propagation speed of the supporting layer is greater than that of the
surface acoustic wave propagation speed of the piezoelectric layer, energy is limited on the surface, and bulk wave leakage is avoided, so that the device loss is reduced; the energy trap layer can improve the Q value to enhance the stability of the
surface acoustic wave resonator.