Title:
PREPARATION METHOD FOR FILM BULK ACOUSTIC RESONATOR, AND FILM BULK ACOUSTIC RESONATOR
Document Type and Number:
WIPO Patent Application WO/2024/001087
Kind Code:
A1
Abstract:
Disclosed in the present invention are a preparation method for a film bulk acoustic resonator, and a film bulk acoustic resonator. The resonator comprises a silicon substrate, a bottom electrode layer, a piezoelectric layer and a top electrode layer, which are arranged in sequence from bottom to top, wherein the top surface of the silicon substrate is provided with a cavity that is dented downward, and the bottom electrode layer is a diphenylene bottom electrode layer. The preparation method comprises step S1: treating a silicon substrate by means of an RCA cleaning process, then drying same, then etching a surface of the silicon substrate to form a groove by means of a dry etching method, and depositing a sacrificial layer on the groove; step S2: depositing a diphenylene bottom electrode layer material on the silicon substrate; step S3: bonding a piezoelectric layer material; step S4: depositing a top electrode layer material, and etching same to obtain a pattern; and step S5: forming a release window around the cavity by means of a dry etching method, injecting an etchant solution from the release window, and removing the loose sacrificial layer, so as to form an air cavity. The present invention can improve both a Q value and an electromechanical coupling coefficient of the resonator.
Inventors:
LI GUOQIANG (CN)
Application Number:
PCT/CN2022/140678
Publication Date:
January 04, 2024
Filing Date:
December 21, 2022
Export Citation:
Assignee:
GUANGZHOU AIFO LIGHT COMMUNICATION TECH CO LTD (CN)
International Classes:
H03H3/02; H03H9/02
Domestic Patent References:
| WO2022116396A1 | 2022-06-09 |
Foreign References:
| CN115333497A | 2022-11-11 | |||
| CN103873010A | 2014-06-18 | |||
| CN109951171A | 2019-06-28 | |||
| CN108291103A | 2018-07-17 |
Attorney, Agent or Firm:
JIAQUAN IP LAW (CN)
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