Surface acoustic wave filter resonator structure with transverse mode suppression effect

Abstract

The invention discloses a SAWR structure with a transverse mode suppression effect. By virtue of a surface acoustic wave resonator utilizing the structure, a transverse mode of the SAWR can be effectively suppressed through the optimal design of structural parameters, so that very high quality factor is realized. A resonator structure for the high-performance surface acoustic wave filter comprisesa piezoelectric monocrystal substrate, an interdigital electrode IDT, a reflecting grating, a busbar and a Si-base perfect matching layer, wherein the interdigital electrode IDT mainly contains an Alor Cu metal material, and the busbar mainly contains the Al or Cu metal material; the standard thickness h of the IDT and a reflecting grating electrode is more than or equal to 0.02lambda and less than or equal to 0.2lambda; and the value range of an aperture w is more than or equal to 20lambda and less than or equal to 50lambda, the value range of a false point length l is more than or equal to2lambda and less than or equal to 10lambda, the value range of an aperture gap g is more than or equal to 0.2lambda and less than or equal to 0.5lambda, the value range of a metallization ratio r ismore than or equal to 0.4lambda and less than or equal to 0.8lambda, and lambda is a resonant wavelength. According to the SAWR structure provided by the invention, by adding a false point and adjusting the length of the false point, the transverse mode interference of the SAWR can be effectively suppressed.

Description

Technical field [0001] The present invention relates to a surface acoustic wave filter resonator structure, in particular to a resonator structure that can effectively suppress transverse modes. Background technique [0002] The resonator is the core of the SAW filter. The design of a high-performance SAW resonator is the key to improving the quality of the SAW filter and broadening its application field. It is also the secret of the technology of different products and the same manufacturer, which is rarely reported in public. [0003] At present, high-performance resonators generally adopt a weighted or asynchronous resonator structure. The design process of this structure is complicated, and the accuracy of material parameters, COM parameters, and technological level are very high. [0004] The invention provides a simple method of suppressing the SAWR transverse mode through false fingers, optimizing the structural parameters of the resonator through finite element simulation, an...

AI Technical Summary

Problems solved by technology

[0003] At present, high-performance resonators generally use weighted or asynchronous resonator structures. The design process of this structure is complicated, and the accuracy and process level of material parameters and COM parameters are very high.

Images