US 12,356,750 B2
Deep trench isolation for cross-talk reduction
Cheng Yu Huang, Hsinchu (TW); Wei-Chieh Chiang, Yuanlin Township (TW); Keng-Yu Chou, Kaohsiung (TW); Chun-Hao Chuang, Hsinchu (TW); Wen-Hau Wu, New Taipei (TW); and Chih-Kung Chang, Zhudong Township (TW)
Assigned to Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Aug. 25, 2021, as Appl. No. 17/411,526.
Claims priority of provisional application 63/184,423, filed on May 5, 2021.
Prior Publication US 2022/0359583 A1, Nov. 10, 2022
Int. Cl. H10F 39/00 (2025.01); H10F 39/18 (2025.01)
CPC H10F 39/807 (2025.01) [H10F 39/011 (2025.01); H10F 39/182 (2025.01); H10F 39/8053 (2025.01); H10F 39/8063 (2025.01)] 16 Claims
OG exemplary drawing
 
1. A CMOS image sensor, comprising:
a substrate having a front-side and a back-side over the front-side;
a plurality of pixel regions comprising a plurality of photodiodes, respectively, configured to receive radiation that enters the substrate from the back-side;
a boundary deep trench isolation (BDTI) structure disposed at boundary regions of the pixel regions and including a first set of BDTI segments extending in a first direction and a second set of BDTI segments extending in a second direction perpendicular to the first direction, such that the BDTI structure laterally surrounds a first photodiode of the plurality of photodiodes, the BDTI structure comprising a first material; and
a pixel deep trench isolation (PDTI) structure disposed within the BDTI structure, the PDTI structure having a bottom surface directly contacting an upper surface of the first photodiode, wherein the PDTI structure comprises a second material that differs from the first material, and includes a first PDTI segment extending in the first direction such that the first PDTI segment is surrounded by the BDTI structure.