US 12,289,097 B2
Acoustic wave filter with overtone mode resonator and fundamental mode resonator
Jiansong Liu, Fremont, CA (US); Kwang Jae Shin, Yongin (KR); Alexandre Augusto Shirakawa, Cardiff by the Sea, CA (US); and Yiliu Wang, Irvine, CA (US)
Assigned to Skyworks Global Pte. Ltd., Singapore (SG)
Filed by Skyworks Global Pte. Ltd., Singapore (SG)
Filed on Feb. 18, 2022, as Appl. No. 17/651,632.
Claims priority of provisional application 63/168,501, filed on Mar. 31, 2021.
Claims priority of provisional application 63/168,568, filed on Mar. 31, 2021.
Prior Publication US 2022/0321101 A1, Oct. 6, 2022
Int. Cl. H03H 9/205 (2006.01); H03F 3/19 (2006.01); H03H 9/13 (2006.01); H03H 9/56 (2006.01); H04B 1/40 (2015.01)
CPC H03H 9/568 (2013.01) [H03F 3/19 (2013.01); H03H 9/13 (2013.01); H03H 9/205 (2013.01); H04B 1/40 (2013.01); H03F 2200/451 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An acoustic wave filter with bulk acoustic wave resonators, the acoustic wave filter comprising:
a first bulk acoustic wave resonator configured to excite an overtone mode as a main mode of the first bulk acoustic wave resonator, the first bulk acoustic wave resonator including a first piezoelectric layer and a second piezoelectric layer, the first piezoelectric layer being stacked with the second piezoelectric layer, and the first piezoelectric layer having a c-axis oriented in a substantially opposite direction than a c-axis of the second piezoelectric layer; and
a second bulk acoustic wave resonator having a fundamental mode as a main mode of the second bulk acoustic wave resonator, the second bulk acoustic wave resonator coupled to the first bulk acoustic wave resonator, and the acoustic wave filter configured to filter a radio frequency signal.