US 11,942,917 B2
Film bulk acoustic resonator and fabrication method thereof
Guohuang Yang, Ningbo (CN)
Assigned to Ningbo Semiconductor International Corporation, Ningbo (CN)
Filed by Ningbo Semiconductor International Corporation, Ningbo (CN)
Filed on Mar. 1, 2021, as Appl. No. 17/249,391.
Application 17/249,391 is a continuation of application No. PCT/CN2020/099741, filed on Jul. 1, 2020.
Claims priority of application No. 201910657440.7 (CN), filed on Jul. 19, 2019.
Prior Publication US 2021/0184643 A1, Jun. 17, 2021
Int. Cl. H03H 3/02 (2006.01); H03H 9/05 (2006.01); H03H 9/17 (2006.01)
CPC H03H 3/02 (2013.01) [H03H 9/0514 (2013.01); H03H 9/173 (2013.01); H03H 2003/021 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A film bulk acoustic resonator, comprising: a substrate; a support layer bonded on the substrate, wherein a cavity, passing through the support layer, is in the support layer; and a second electrode, a piezoelectric layer, and a first electrode which are sequentially disposed in the support layer, wherein sidewalls of one end of the first electrode and one end of the piezoelectric layer are coplanar with each other and are within the cavity along a vertical direction of the substrate, and the second electrode covers the cavity and extends at least partially over the support layer outwards the cavity along a lateral direction of the substrate, an etch stop layer is disposed between the second electrode and the support layer and sidewalls of an end of each of the second electrode, the piezoelectric layer, the first electrode and the etch stop layer are coplanar with each other and are outside of the cavity along the vertical direction of the substrate.