US 11,855,607 B2
Electro-acoustic resonator and method of forming thereof
Matthias Honal, Munich (DE); Tomasz Jewula, Markt Schwaben (DE); Pei Wen Qiao, Singapore (SG); Siew Li Poh, Singapore (SG); and Siew Ling Koh, Singapore (SG)
Assigned to RF360 Singapore Pte. Ltd., San Diego, CA (US)
Appl. No. 17/046,705
Filed by RF360 SINGAPORE PTE. LTD., Singapore (SG)
PCT Filed Apr. 24, 2019, PCT No. PCT/EP2019/060497
§ 371(c)(1), (2) Date Oct. 9, 2020,
PCT Pub. No. WO2019/206986, PCT Pub. Date Oct. 31, 2019.
Claims priority of application No. 102018109849.9 (DE), filed on Apr. 24, 2018.
Prior Publication US 2021/0075397 A1, Mar. 11, 2021
Int. Cl. H03H 9/02 (2006.01); H03H 9/145 (2006.01); H03H 3/08 (2006.01); H03H 9/25 (2006.01)
CPC H03H 9/14541 (2013.01) [H03H 3/08 (2013.01); H03H 9/02559 (2013.01); H03H 9/02937 (2013.01); H03H 9/25 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An electro-acoustic resonator, comprising:
a substrate, the substrate having piezoelectric properties; and
an electrode structure disposed on the substrate, the electrode structure comprising:
a metal layer, the metal layer comprising aluminum and copper, wherein, within the metal layer, a mass of the copper is substantially equal to a mass of the aluminum;
a barrier layer disposed on the metal layer and configured to form a barrier against a diffusion of copper; and
another metal layer disposed on the barrier layer, the other metal layer comprising aluminum.