US 12,451,863 B2
Bulk acoustic wave resonator and method of manufacturing bulk acoustic wave resonator
Jin Nyoung Jang, Gyeonggi-do (KR); Kang Ho Kim, Gyeonggi-do (KR); Yun Sik Choi, Gyeonggi-do (KR); and Joon Sung Kwon, Gyeonggi-do (KR)
Assigned to WISOL CO., LTD., Gyeonggi-do (KR)
Filed by WISOL CO., LTD., Gyeonggi-do (KR)
Filed on Aug. 16, 2022, as Appl. No. 17/888,633.
Claims priority of application No. 10-2021-0109434 (KR), filed on Aug. 19, 2021.
Prior Publication US 2023/0075102 A1, Mar. 9, 2023
Int. Cl. H03H 9/17 (2006.01); H03H 3/02 (2006.01); H03H 9/13 (2006.01)
CPC H03H 9/17 (2013.01) [H03H 3/02 (2013.01); H03H 9/131 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method of manufacturing a bulk acoustic wave (BAW) resonator, comprising:
forming a lower electrode above a substrate;
forming a nitrogen layer on an upper surface of the lower electrode through nitrogen (N2) plasma surface treatment;
forming a piezoelectric layer made of an AlScN material above the nitrogen layer to align an upper surface of the piezoelectric layer to an N polarity; and
forming an upper electrode above the piezoelectric layer aligned to the N polarity.