US 11,843,365 B2
Bulk-acoustic wave resonator
Tae Kyung Lee, Suwon-si (KR); Won Han, Suwon-si (KR); Moon Chul Lee, Suwon-si (KR); Sang Uk Son, Suwon-si (KR); and Hwa Sun Lee, Suwon-si (KR)
Assigned to Samsung Electro-Mechanics Co., Ltd., Suwon-si (KR)
Filed by SAMSUNG ELECTRO-MECHANICS CO., LTD., Suwon-si (KR)
Filed on Jan. 8, 2021, as Appl. No. 17/144,602.
Claims priority of application No. 10-2020-0093989 (KR), filed on Jul. 28, 2020.
Prior Publication US 2022/0038075 A1, Feb. 3, 2022
Int. Cl. H03H 9/17 (2006.01); H03H 9/02 (2006.01)
CPC H03H 9/173 (2013.01) [H03H 9/02118 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A bulk-acoustic wave resonator, comprising:
a resonator including a central portion in which a first electrode, a piezoelectric layer, and a second electrode are sequentially stacked on a substrate, and an extension portion disposed along a periphery of the central portion; and
an insertion layer disposed between the piezoelectric layer and the substrate in the extension portion,
wherein the insertion layer comprises a first insertion layer having a first inclined surface formed along a side surface facing the central portion and a second insertion layer disposed between the first insertion layer and the piezoelectric layer and having a second inclined surface spaced apart from the first inclined surface with respect to a surface direction of the first electrode, and
wherein the first insertion layer is thinner than the second insertion layer.