US 11,876,498 B2
Transversely-excited film bulk acoustic resonator with multiple diaphragm thicknesses and fabrication method
Ventsislav Yantchev, Sofia (BG); Patrick Turner, San Bruno, CA (US); and Robert B. Hammond, Santa Barbara, CA (US)
Assigned to MURATA MANUFACTURING CO., LTD., Nagaokakyo (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Jun. 17, 2021, as Appl. No. 17/351,201.
Application 17/351,201 is a continuation of application No. 16/988,213, filed on Aug. 7, 2020, granted, now 11,201,601.
Application 16/988,213 is a continuation in part of application No. 16/438,121, filed on Jun. 11, 2019, granted, now 10,756,697, issued on Aug. 25, 2020.
Application 16/438,121 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 62/904,152, filed on Sep. 23, 2019.
Claims priority of provisional application 62/892,980, filed on Aug. 28, 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 2021/0313963 A1, Oct. 7, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. H03H 9/56 (2006.01); H03H 9/02 (2006.01); H03H 9/205 (2006.01); H03H 3/04 (2006.01); H03H 9/54 (2006.01); H03H 3/02 (2006.01); H03H 9/17 (2006.01)
CPC H03H 9/568 (2013.01) [H03H 3/02 (2013.01); H03H 3/04 (2013.01); H03H 9/02015 (2013.01); H03H 9/02157 (2013.01); H03H 9/02228 (2013.01); H03H 9/174 (2013.01); H03H 9/205 (2013.01); H03H 9/54 (2013.01); H03H 9/564 (2013.01); H03H 9/566 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A filter device, comprising:
a substrate;
at least one piezoelectric layer attached directly to the substrate or by one or more intermediate material layers, the at least one piezoelectric layer comprising a plurality of diaphragms that are over a plurality of cavities, respectively, in at least one of the substrate and the one or more intermediate material layers, wherein:
a first portion of the at least one piezoelectric layer has a first thickness, and
a surface of a second portion of the at least one piezoelectric layer is recessed relative to a surface of the first portion of the at least one piezoelectric layer such that the second portion of the at least one piezoelectric layer has a second thickness less than the first thickness; and
a conductor pattern at the first and second portions of the at least one piezoelectric layer, the conductor pattern comprising:
a first interdigital transducer (IDT) with interleaved fingers on a diaphragm having the first thickness, and
a second IDT with interleaved fingers on a diaphragm having the second thickness.