US 11,870,414 B2
Film bulk acoustic resonator chip and package structure with improved temperature coefficient
Young Hun Kim, Osan-si (KR)
Assigned to WISOL CO., LTD., Osan-si (KR)
Filed by WISOL CO., LTD., Osan-si (KR)
Filed on Jan. 26, 2021, as Appl. No. 17/158,372.
Claims priority of application No. 10-2020-0104684 (KR), filed on Aug. 20, 2020.
Prior Publication US 2022/0060169 A1, Feb. 24, 2022
Int. Cl. H03H 9/02 (2006.01); H03H 9/205 (2006.01); H03H 9/17 (2006.01)
CPC H03H 9/02102 (2013.01) [H03H 9/173 (2013.01); H03H 9/205 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A film bulk acoustic resonator (FBAR) chip and package structure with an improved temperature coefficient, comprising:
a plurality of FBARs located on a central area of one surface of a substrate and each having a bottom electrode, a piezoelectric material, and a top electrode; and
a temperature compensation layer formed outside each of the plurality of FBARs around the central area of one surface of the substrate,
wherein the temperature compensation layer is formed on the substrate to completely surround the central area of one surface of the substrate,
wherein the temperature compensation layer comes into contact with the piezoelectric materials of the FBARs in such a manner as to be formed on the outsides of the piezoelectric materials,
wherein when viewed on top of the substrate, the boundary line between the temperature compensation layer and the piezoelectric materials is irregularly formed with a concave/convex shape along the FBARs arranged on the substrate.