US 11,671,074 B2
Recess frame structure for a bulk acoustic wave resonator
Nobufumi Matsuo, Suita (JP); and Kwang Jae Shin, Yongin (KR)
Assigned to SKYWORKS GLOBAL PTE. LTD., Singapore (SG)
Filed by SKYWORKS GLOBAL PTE. LTD., Singapore (SG)
Filed on Sep. 12, 2019, as Appl. No. 16/568,439.
Claims priority of provisional application 62/836,130, filed on Apr. 19, 2019.
Claims priority of provisional application 62/730,128, filed on Sep. 12, 2018.
Prior Publication US 2020/0083861 A1, Mar. 12, 2020
Int. Cl. H03H 9/17 (2006.01); H03H 3/02 (2006.01); H03H 9/00 (2006.01); H03H 9/02 (2006.01); H03H 9/13 (2006.01); H03H 9/56 (2006.01); H03H 9/70 (2006.01)
CPC H03H 9/173 (2013.01) [H03H 3/02 (2013.01); H03H 9/0014 (2013.01); H03H 9/0211 (2013.01); H03H 9/13 (2013.01); H03H 9/564 (2013.01); H03H 9/706 (2013.01); H03H 2003/021 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A film bulk acoustic wave resonator (FBAR) comprising:
a piezoelectric film disposed in a central region defining a main active domain in which a main acoustic wave is generated during operation, and in recessed frame regions disposed laterally on opposite sides of the central region, the piezoelectric film disposed in the recessed frame regions including a greater concentration of defects than a concentration of defects in the piezoelectric film disposed in the central region;
a bottom electrode disposed below the piezoelectric film; and
a seed layer of piezoelectric material disposed between and contacting each of the piezoelectric film and bottom electrode in the central region, but not in the recessed frame region.