Radio frequency piezoelectric resonator with adjustable reflection cavity and preparation method

Abstract

The invention provides a radio frequency piezoelectric resonator with an adjustable reflection cavity and a preparation method thereof. The radio frequency piezoelectric resonator comprises a resonator substrate 1, a sacrificial layer 2, a smoothing anti-etching material 5, a resonator flat plate bottom electrode 6, a resonator piezoelectric material 7, a resonator cross upper electrode 8, a piezoelectric layer etching window 9 and an air reflection cavity 10. The resonator substrate 1 can support a radio frequency piezoelectric resonator with an adjustable reflection cavity; the sacrificial layer 2 is formed on the resonator substrate 1; the smoothing anti-etching material 5 is formed in the sacrificial layer 2; the resonator bottom electrode 6 is of a flat plate structure; the resonatorupper electrode 8 adopts a cross structure; the resonator bottom electrode 6 can be crossed with the resonator upper electrode 8 to form an electric field; the resonator piezoelectric material 7 is apiezoelectric film material; and the piezoelectric layer etching window 9 comprises a sacrificial layer inlet unit. The radio frequency piezoelectric resonator has the advantages of single-chip integration and multi-frequency, and overcomes the defects of single chip and single frequency of a traditional bulk acoustic wave thin film resonator.

Description

technical field [0001] The present invention relates to the field of wireless communication, in particular to a radio frequency piezoelectric resonator with an adjustable reflective cavity and a preparation method thereof, in particular to a radio frequency piezoelectric resonator structure with adjustable frequency and adjustable reflective cavity performance. Background technique [0002] With the rapid development of 5G communication, various communication systems (such as mobile phones, tablets, automatic driving, micro base stations, etc.) have higher and higher performance requirements for RF piezoelectric filters, especially for high frequency, high quality factor, single On-chip integrated multi-frequency filter needs. The piezoelectric resonator is the core unit of the piezoelectric filter, and its performance will directly affect the performance of the filter. In the prior art, there is an urgent need for a radio frequency piezoelectric resonator structure with ad...

AI Technical Summary

Problems solved by technology

The disadvantage of the existing technology is: the resonator in the comparative patent cannot flexibly place the piezoelectric etching window, which will lead to the instability of the final device structure

There is still room for improvement in the stability of the structure of this patent

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