US 12,451,865 B2
Acoustic wave device
Sho Nagatomo, Nagaokakyo (JP); Bryant Garcia, Mississauga (CA); Ventsislav Yantchev, Sofia (BG); Patrick Turner, Portola Valley, CA (US); Robert B. Hammond, Rockville, MD (US); and Douglas Jachowski, Santa Cruz, CA (US)
Assigned to MURATA MANUFACTURING CO., LTD., Nagaokakyo (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Nov. 16, 2023, as Appl. No. 18/510,873.
Application 18/510,873 is a continuation of application No. PCT/US2022/029491, filed on May 16, 2022.
Claims priority of provisional application 63/189,436, filed on May 17, 2021.
Prior Publication US 2024/0097649 A1, Mar. 21, 2024
Int. Cl. H03H 9/205 (2006.01); H03H 9/02 (2006.01)
CPC H03H 9/205 (2013.01) [H03H 9/02015 (2013.01); H03H 9/02157 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An acoustic wave device comprising:
a first resonator including:
a piezoelectric substrate including a piezoelectric layer;
a first functional electrode on the piezoelectric layer; and
a first dielectric film on the piezoelectric layer and covering the first functional electrode; and
a second resonator that includes the piezoelectric layer, the second resonator including:
a second functional electrode on the piezoelectric layer; and
a second dielectric film on the piezoelectric layer and covering the second functional electrode,
wherein the piezoelectric layer includes a first resonator portion and a second resonator portion, a portion of the first resonator being in the first resonator portion, a portion of the second resonator being in the second resonator portion;
wherein a resonant frequency of the first resonator is lower than a resonant frequency of the second resonator and, in the piezoelectric layer, a thickness of the first resonator portion is greater than a thickness of the second resonator portion, and
wherein ts1/tp1≤ts2/tp2, where tp1 is the thickness of the first resonator portion, tp2 is the thickness of the second resonator portion, ts1 is a thickness of the first dielectric film, and tp2 is a thickness of the second dielectric film.