US 12,255,617 B2
Solidly-mounted transversely-excited film bulk acoustic resonators with low thermal impedance
Greg Dyer, Santa Barbara, CA (US); Chris O'Brien, San Diego, CA (US); Neal O. Fenzi, Santa Barbara, CA (US); and James R. Costa, Lompoc, CA (US)
Assigned to MURATA MANUFACTURING CO., LTD., Nagaokakyo (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Feb. 2, 2022, as Appl. No. 17/591,577.
Application 17/591,577 is a continuation in part of application No. 17/217,923, filed on Mar. 30, 2021, granted, now 11,936,358.
Claims priority of provisional application 63/112,395, filed on Nov. 11, 2020.
Prior Publication US 2022/0158615 A1, May 19, 2022
Int. Cl. H03H 9/17 (2006.01); H03H 9/13 (2006.01); H03H 9/54 (2006.01)
CPC H03H 9/17 (2013.01) [H03H 9/13 (2013.01); H03H 9/54 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An acoustic resonator comprising:
a substrate;
a piezoelectric plate;
an acoustic Bragg reflector between a surface of the substrate and a back surface of the piezoelectric plate; and
an interdigital transducer (IDT) on a front surface of the piezoelectric plate, the IDT comprising first and second busbars and a plurality of interleaved fingers extending alternately from the first and second busbars,
wherein at least a portion of the first busbar contacts the substrate through an opening in the piezoelectric plate and the acoustic Bragg reflector.