US 12,040,778 B2
High frequency, high power film bulk acoustic resonators
Bryant Garcia, Burlingame, CA (US); Robert Hammond, Santa Barbara, CA (US); Patrick Turner, San Bruno, CA (US); Neal Fenzi, Santa Barbara, CA (US); Viktor Plesski, Gorgier (CH); and Ventsislav Yantchev, Sofia (BG)
Assigned to MURATA MANUFACTURING CO., LTD., Nagaokakyo (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Feb. 4, 2021, as Appl. No. 17/167,909.
Application 17/167,909 is a continuation of application No. 16/996,381, filed on Aug. 18, 2020, granted, now 10,985,730.
Application 16/996,381 is a continuation of application No. 16/829,617, filed on Mar. 25, 2020, granted, now 10,868,512, issued on Dec. 15, 2020.
Application 16/829,617 is a continuation of application No. 16/578,811, filed on Sep. 23, 2019, granted, now 10,637,438, issued on Apr. 28, 2020.
Application 16/578,811 is a continuation in part of application No. 16/230,443, filed on Dec. 21, 2018, granted, now 10,491,192, issued on Nov. 26, 2019.
Claims priority of provisional application 62/753,815, filed on Oct. 31, 2018.
Claims priority of provisional application 62/748,883, filed on Oct. 22, 2018.
Claims priority of provisional application 62/741,702, filed on Oct. 5, 2018.
Claims priority of provisional application 62/701,363, filed on Jul. 20, 2018.
Claims priority of provisional application 62/685,825, filed on Jun. 15, 2018.
Prior Publication US 2021/0194458 A1, Jun. 24, 2021
Int. Cl. H03H 9/17 (2006.01); H03H 9/02 (2006.01); H03H 9/54 (2006.01); H03H 9/13 (2006.01)
CPC H03H 9/171 (2013.01) [H03H 9/02 (2013.01); H03H 9/54 (2013.01); H03H 9/02015 (2013.01); H03H 9/13 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An acoustic resonator device comprising:
a substrate that includes a base and an intermediate layer having a surface;
a piezoelectric plate supported by the substrate and having a portion that forms a diaphragm over a cavity; and
an interdigital transducer (IDT) at a surface of the piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm,
wherein a thickness of the interleaved fingers of the IDT is less than 0.375 times the thickness of the diaphragm,
wherein a ratio of a pitch of the interleaved fingers is between 2 and 20 times a width of the interleaved fingers, and
wherein the piezoelectric plate and the IDT are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm, the primary shear acoustic mode being a bulk shear mode where acoustic energy propagates along a direction substantially orthogonal to the surface of the piezoelectric plate and transverse to a direction of an electric field created by the IDT.