US 12,456,962 B2
Transversely-excited film bulk acoustic resonators wafer-level packaging using a dielectric cover
Dylan Kelly, San Diego, CA (US); Andrew Guyette, San Mateo, CA (US); 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 Sep. 23, 2022, as Appl. No. 17/952,164.
Claims priority of provisional application 63/247,910, filed on Sep. 24, 2021.
Prior Publication US 2023/0096387 A1, Mar. 30, 2023
Int. Cl. H03H 9/17 (2006.01); H03H 3/02 (2006.01); H03H 9/02 (2006.01); H03H 9/13 (2006.01); H03H 9/56 (2006.01)
CPC H03H 9/173 (2013.01) [H03H 3/02 (2013.01); H03H 9/133 (2013.01); H03H 9/568 (2013.01); H03H 2003/021 (2013.01); H03H 9/02157 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An acoustic resonator device comprising:
a substrate having a surface;
a piezoelectric layer attached to the surface of the substrate via an intermediate layer, the piezoelectric layer including a portion that forms a diaphragm that is over a cavity;
a conductor pattern including an interdigital transducer (IDT) on a surface of the piezoelectric layer and having interleaved fingers on the diaphragm; and
a dielectric cover over the IDT and the piezoelectric layer, the dielectric cover including a bottom surface attached to a portion of the conductor pattern, wherein the conductor pattern includes at least one metal layer, and wherein the dielectric cover is attached to the at least one metal layer,
wherein the dielectric cover forms an air gap above the IDT and the piezoelectric layer.