公开(公告)号：US20250002333A1

公开(公告)日：2025-01-02

申请号：US18215322

申请日：2023-06-28

Applicant: STMicroelectronics International N.V.

Inventor： Eric SAUGIER

IPC: B81C1/00 ,  B81B7/02

Abstract: Wafer level proximity sensors are formed by processing a silicon substrate wafer and a silicon cap wafer separately, bonding the cap wafer to the substrate wafer to form a bonded wafer sandwich, and then selectively thinning the silicon substrate wafer and silicon cap wafer. The silicon substrate wafer is thinned first, and an interconnect structure of through-silicon vias is formed within the thinned silicon substrate wafer. The silicon cap wafer is then thinned to expose openings facing an area of the thinned silicon substrate wafer where a photosensitive region is location and facing an area of the thinned silicon substrate wafer where an emitter die is to be installed. After emitter die installation, the openings in the thinned silicon cap wafer are filled with a transparent material. The thinned silicon cap wafer further includes an opaque light barrier to block light transmission between the openings.