	US 12,113,503 B2
	Manufacturing process for bulk acoustic resonator, and bulk acoustic resonator
Linping Li, Zhejiang (CN); Jinghao Sheng, Zhejiang (CN); and Zhou Jiang, Zhejiang (CN)
Assigned to HANGZHOU XINGHE TECHNOLOGY CO., LTD., (CN)
Appl. No. 18/028,122
Filed by HANGZHOU XINGHE TECHNOLOGY CO., LTD., Zhejiang (CN)
PCT Filed Sep. 27, 2020, PCT No. PCT/CN2020/118175 § 371(c)(1), (2) Date Mar. 23, 2023, PCT Pub. No. WO2022/061835, PCT Pub. Date Mar. 31, 2022.
Claims priority of application No. 202011024256.8 (CN), filed on Sep. 25, 2020.
Prior Publication US 2023/0327627 A1, Oct. 12, 2023
Int. Cl. H03H 3/02 (2006.01); H03H 9/02 (2006.01); H03H 9/17 (2006.01)

CPC H03H 3/02 (2013.01) [H03H 9/02125 (2013.01); H03H 9/175 (2013.01); H03H 2003/025 (2013.01)]

13 Claims

1. A manufacturing process method for a bulk acoustic resonator, comprising:

step S1: making an acoustic mirror on a substrate;

step S2: making, on the substrate, a bottom electrode layer for covering the acoustic mirror;

step S3: performing chemical treatment on a peripheral part of the bottom electrode layer to form a modified layer, wherein the modified layer surrounds the bottom electrode layer;

step S4: making a piezoelectric layer on the bottom electrode layer; and

step S5: making a top electrode layer on the piezoelectric layer,

wherein the modified layer is formed by performing at least local chemical treatment on the peripheral part of the bottom electrode layer.