US 11,901,878 B2
Transversely-excited film bulk acoustic resonators with two-layer electrodes with a wider top layer
Viktor Plesski, Gorgier (CH); Bryant Garcia, Burlingame, CA (US); Julius Koskela, Helsinki (FI); and Patrick Turner, San Bruno, CA (US)
Assigned to MURATA MANUFACTURING CO., LTD., Nagaokakyo (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Dec. 23, 2020, as Appl. No. 17/133,389.
Application 17/133,389 is a continuation in part of application No. 16/944,831, filed on Jul. 31, 2020, granted, now 11,114,996.
Application 16/944,831 is a continuation of application No. 16/779,255, filed on Jan. 31, 2020, granted, now 10,826,462, issued on Nov. 3, 2020.
Application 16/779,255 is a continuation in part 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 62/926,181, filed on Oct. 25, 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 2021/0126621 A1, Apr. 29, 2021
Int. Cl. H03H 9/54 (2006.01); H03H 9/13 (2006.01); H03H 9/02 (2006.01); H03H 3/04 (2006.01)
CPC H03H 9/547 (2013.01) [H03H 3/04 (2013.01); H03H 9/02228 (2013.01); H03H 9/02559 (2013.01); H03H 9/132 (2013.01)] 27 Claims
OG exemplary drawing
 
1. An acoustic resonator device comprising:
a substrate having a surface;
a single-crystal piezoelectric plate having front and back surfaces, the back surface attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate; and
an interdigital transducer formed on the front surface of the piezoelectric plate, interleaved fingers of the IDT disposed on the diaphragm configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm,
wherein the interleaved fingers comprise a first layer adjacent the diaphragm and a second layer over the first layer, the second layer having a greater width than the first layer.