US 11,942,915 B2
Bulk acoustic wave resonator device and method of manufacturing thereof
Ulrike Roesler, Munich (DE); Willi Aigner, Moosinning (DE); Maximilian Schiek, Puchheim (DE); and Giuseppe Toscano, Munich (DE)
Assigned to RF360 Singapore Pte. Ltd., Republic Plaza (SG)
Appl. No. 17/042,698
Filed by RF360 EUROPE GMBH, Munich (DE)
PCT Filed Mar. 7, 2019, PCT No. PCT/EP2019/055761
§ 371(c)(1), (2) Date Sep. 28, 2020,
PCT Pub. No. WO2019/185324, PCT Pub. Date Oct. 3, 2019.
Claims priority of application No. 10 2018 107 496.4 (DE), filed on Mar. 28, 2018.
Prior Publication US 2021/0058050 A1, Feb. 25, 2021
Int. Cl. H03H 3/02 (2006.01); H03H 9/02 (2006.01); H03H 9/17 (2006.01); H10N 30/072 (2023.01)
CPC H03H 3/02 (2013.01) [H03H 9/02015 (2013.01); H03H 9/174 (2013.01); H03H 9/175 (2013.01); H10N 30/072 (2023.02); H03H 2003/023 (2013.01); H03H 2003/025 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A bulk acoustic wave resonator device, comprising:
a bottom electrode and a top electrode; and
a piezoelectric layer having a first portion disposed between the bottom electrode and the top electrode, the first portion having a thickness, the piezoelectric layer having a second portion on at least two sides of the first portion, the second portion having a thickness different from the thickness of the first portion, wherein the piezoelectric layer has a first surface facing the bottom electrode and a second surface opposite the first surface, the second surface including: a first surface portion facing the top electrode; a second surface portion associated with at least a portion of the second portion of the piezoelectric layer; and a transitional surface portion disposed between the first and second surface portions of the second surface, wherein the transitional surface portion has an oblique orientation with regard to the first surface portion and the second surface portion of the second surface.