US 12,289,091 B2
Piezoelectric film acoustic resonator
Shuai Yang, Shenzhen (CN); Lirong Zhang, Shenzhen (CN); Ke Wu, Shenzhen (CN); Zhiqiang Zhuang, Shenzhen (CN); and Chao Wang, Shenzhen (CN)
Assigned to AAC Technologies (Nanjing) Co., Ltd., Nanjing (CN); and AAC ACOUSTIC TECHNOLOGIES (SHENZHEN) CO., LTD., Shenzhen (CN)
Filed by AAC Technologies (Nanjing) Co., Ltd., Nanjing (CN); and AAC ACOUSTIC TECHNOLOGIES (SHENZHEN) CO., LTD., Shenzhen (CN)
Filed on Dec. 31, 2021, as Appl. No. 17/566,711.
Claims priority of application No. 202122961003.X (CN), filed on Nov. 29, 2021.
Prior Publication US 2023/0170874 A1, Jun. 1, 2023
Int. Cl. H03H 9/02 (2006.01); H03H 9/17 (2006.01)
CPC H03H 9/02118 (2013.01) [H03H 9/175 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A piezoelectric film acoustic resonator, comprising:
a substrate,
a first electrode disposed over the substrate,
a piezoelectric film disposed over the substrate and covering at least a portion of the first electrode,
a second electrode disposed on a surface of the piezoelectric film away from the first electrode,
and an acoustic mirror arranged under the first electrode,
the projections of the substrate, the acoustic mirror, the first electrode, the piezoelectric film and the second electrode in the thickness direction of the piezoelectric film are at least partially overlapped, a resonance region where the projections of the substrate, the acoustic mirror, the first electrode, the piezoelectric film and the second electrode are overlapped is formed,
one end of the first electrode extends in the direction away from the piezoelectric film to form a first extended pad, one end of the second electrode extends in the direction away from the first extended pad to form a second extended pad,
wherein, a first protruding reflection grating is disposed on the surface of the first extended pad away from the substrate, a second protruding reflection grating is disposed on the surface of the second extended pad away from the substrate.