Overall lattice reflection weighted surface acoustic wave resonator

Abstract

The invention provides an overall lattice reflection weighted surface acoustic wave resonator comprising a piezoelectric substrate, wherein a metal interdigital transducer and a reflecting grating are sputtered on the piezoelectric substrate, the reflecting grating comprises a first short circuit grating and a second short circuit grating arranged on left and right sides of the metal interdigital transducer, the first short circuit grating and the second short circuit grating are symmetrically distributed on the left and right sides of the metal interdigital transducer, and metal lattices are respectively arranged between a false point of the metal interdigital transducer and an adjacent electrode, between adjacent grid bars of the first short circuit grating and between adjacent grid bars of the second short circuit grating. The overall lattice reflection weighted surface acoustic wave resonator provided by the invention has the beneficial effects that the metal weighing lattices are arranged on the false point of the metal interdigital transducer, the first short circuit grating and the second short circuit grating to reduce the side peak interference caused by the metal interdigital transducer and the reflection of the reflecting grating and improve the frequency response performance of the SAW resonator.

Description

technical field [0001] The invention belongs to the technical field of signal and information processing, and in particular relates to a surface acoustic wave resonator with integral lattice reflection weighting. Background technique [0002] A general SAW resonator is a metal interdigital transducer (Interdigital Transducer, IDT) and a reflection grid processed on the surface of a piezoelectric substrate. Usually a resonator is only concerned with the performance of the main formant. However, due to the periodic and unweighted structure of the IDT false finger and the reflective grid, the side peaks are relatively high. [0003] Literature "Analysis of general planar waveguides with N segments," (IEEE Ultrason.Symp., pp.137–141, 2000.) and "Surface Acoustic Wave Device Simulation and Simulation" edited by Ken-ya Hashimoto (pp.213-218) It is pointed out that there are more side peak fluctuations outside the main resonance peak. The basic principle is as follows figure 1 s...

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Problems solved by technology

This invention eliminates the high-order shear wave mode through the aperiodicity in the Y direction, but it does not suppress the first type of side peaks

[0007] The document "Apodization Weighted SAW Temperature Sensor Design Based on Hamming Function" (Electronic Components and Materials, Vol. 30, No. 11, pp.38-41, 2011) proposes that the IDT is weighted by the Hamming function, and the weight of the IDT part can be partially reduced Transduction affects the suppression of the first type of side peaks, but the first type of side peaks caused by IDT and reflective grid reflections are not considered

[0008] The lattice weighting applied in the patent "Surface Acoustic Wave Resonator with Lattice Structure" (Application No. 201310210349.3)" only appears in the reflective grating part, which suppresses the first type of side peak mode suppression caused by the periodic reflective grating, but has no effect on IDT internal reflection The side peaks caused by the first type are not considered

[0009] The above structures all try to reduce side peak interference, but none of them mentioned that in the first type of side peak, the suppression of acoustic wave side peak mode caused by IDT and reflective grid reflection is comprehensively considered, so this technology needs to be further improved and developed

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