US 12,308,827 B2
Multilayer piezoelectric substrate device with positive temperature coefficient of frequency dielectric film for temperature stability
Rei Goto, Osaka (JP); and Hironori Fukuhara, Ibaraki (JP)
Assigned to Skyworks Solutions, Inc., Irvine, CA (US)
Filed by Skyworks Solutions, Inc., Irvine, CA (US)
Filed on Sep. 1, 2022, as Appl. No. 17/929,066.
Claims priority of provisional application 63/262,547, filed on Oct. 14, 2021.
Claims priority of provisional application 63/262,551, filed on Oct. 14, 2021.
Claims priority of provisional application 63/262,546, filed on Oct. 14, 2021.
Prior Publication US 2023/0117464 A1, Apr. 20, 2023
Int. Cl. H03H 9/64 (2006.01); H03H 9/02 (2006.01); H03H 9/10 (2006.01); H03H 9/145 (2006.01); H03H 9/54 (2006.01)
CPC H03H 9/6489 (2013.01) [H03H 9/02559 (2013.01); H03H 9/02574 (2013.01); H03H 9/02637 (2013.01); H03H 9/02834 (2013.01); H03H 9/1064 (2013.01); H03H 9/14544 (2013.01); H03H 9/54 (2013.01); H03H 9/6483 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An acoustic wave filter comprising:
a substrate;
a piezoelectric layer disposed over the substrate;
a first plurality of acoustic wave resonators disposed over the piezoelectric layer and arranged in series along a first branch, each of the first plurality of acoustic wave resonators including an interdigital transducer electrode interposed between a pair of reflectors;
a second plurality of acoustic wave resonators disposed over the piezoelectric layer and arranged in parallel, each of the second plurality of acoustic wave resonators including an interdigital transducer electrode interposed between a pair of reflectors and being connected to the first branch and to ground; and
a layer of positive temperature coefficient of frequency dielectric material disposed over one or more of the first plurality of acoustic wave resonators and having a first height above the substrate, and a second layer of positive temperature coefficient of frequency dielectric material disposed over one or more of the second plurality of acoustic wave resonators and having a second height above the substrate that is smaller than the first height.