US 12,230,552 B2
Recess structure for padless stack via
Hong Bok We, San Diego, CA (US); Joan Rey Villarba Buot, Escondido, CA (US); and Aniket Patil, San Diego, CA (US)
Assigned to QUALCOMM INCORPORATED, San Diego, CA (US)
Filed by QUALCOMM Incorporated, San Diego, CA (US)
Filed on Nov. 18, 2021, as Appl. No. 17/455,576.
Prior Publication US 2023/0154829 A1, May 18, 2023
Int. Cl. H01L 23/48 (2006.01); H01L 21/768 (2006.01); H01L 23/498 (2006.01)
CPC H01L 23/481 (2013.01) [H01L 21/76804 (2013.01); H01L 21/76898 (2013.01)] 30 Claims
OG exemplary drawing
 
1. A stack via structure, comprising:
a capture pad;
a first via stacked over and electrically coupled with the capture pad;
a second via stacked over and electrically coupled with the first via;
a cover pad stacked over and electrically coupled with the second via;
a first dielectric layer encapsulating sides of the first via, wherein a top surface of the first via and a top surface of the first dielectric layer are coplanar; and
a second dielectric layer formed on the first dielectric layer and encapsulating sides of the second via,
wherein a top width the first via is wider than a bottom width of the second via,
wherein a recess is formed in the first via to partially extend into the top surface thereof, and
wherein a bottom portion of the second via is within the recess, the bottom portion of the second via extending from a bottom surface thereof up to a height equal to a depth of the recess, the second via being in contact with the first via within the recess.