US 12,308,822 B2
Saw multiplexer with SWA filters having different bandwidths due to dielectric layer between IDT and piezoelectric layer adjusting acoupling factor
Peter Laaser, Bavaria (DE)
Assigned to RF360 Singapore Pte. Ltd., Republic Plaza (SG)
Appl. No. 17/641,406
Filed by RF360 SINGAPORE PTE. LTD., Republic Plaza (SG)
PCT Filed Sep. 9, 2020, PCT No. PCT/EP2020/075201
§ 371(c)(1), (2) Date Mar. 8, 2022,
PCT Pub. No. WO2021/052836, PCT Pub. Date Mar. 25, 2021.
Claims priority of application No. 10 2019 124 861.2 (DE), filed on Sep. 16, 2019.
Prior Publication US 2022/0329229 A1, Oct. 13, 2022
Int. Cl. H03H 9/145 (2006.01); H03H 9/25 (2006.01); H03H 9/64 (2006.01)
CPC H03H 9/145 (2013.01) [H03H 9/25 (2013.01); H03H 9/64 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A filter chip comprising:
a first-type filter disposed on the filter chip and comprising a first-type surface acoustic wave (SAW)-resonator; and
a plurality of second-type filters disposed on the filter chip, each second-type filter comprising at least one second-type SAW-resonator;
wherein the first-type SAW-resonator comprises a piezoelectric layer, an intermediate layer on the piezoelectric layer, and an interdigital electrode structure on the intermediate layer, the interdigital electrode structure is separated from the piezoelectric layer by the intermediate layer, and the intermediate layer includes a dielectric, non-piezoelectric material; and
wherein the at least one second-type SAW-resonator comprises the piezoelectric layer and the interdigital electrode structure applied on top of the piezoelectric layer.