US 12,293,940 B2
Techniques for forming a deep trench isolation structure between photodiodes by forming a first set of trenches based on a first pattern and forming a second set of trenches based on a second pattern
Wei-Chao Chiu, Hsinchu (TW); Yu-Wen Chen, Hsinchu (TW); Yong-Jin Liou, Hsinchu (TW); Chun-Wei Chang, Tainan (TW); Ching-Sen Kuo, Taipei (TW); and Feng-Jia Shiu, Jhudong Township (TW)
Assigned to Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed on Aug. 10, 2023, as Appl. No. 18/447,547.
Application 18/447,547 is a division of application No. 17/303,524, filed on Jun. 1, 2021.
Claims priority of provisional application 63/200,387, filed on Mar. 4, 2021.
Prior Publication US 2023/0402315 A1, Dec. 14, 2023
Int. Cl. H01L 21/762 (2006.01); H01L 21/3065 (2006.01); H01L 27/146 (2006.01)
CPC H01L 21/76224 (2013.01) [H01L 21/3065 (2013.01); H01L 27/14643 (2013.01); H01L 27/14689 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
forming a hard mask layer over an oxide layer, wherein the oxide layer is over a removable dielectric layer that is over a substrate;
forming a first portion of a pattern in a first direction in the hard mask layer based on removing one or more portions of the hard mask layer up to the oxide layer;
forming, subsequent to forming the first portion of the pattern, a second portion of the pattern in a second direction in the hard mask layer based on removing one or more other portions of the hard mask layer up to the oxide layer;
etching, based on the first portion of the pattern and the second portion of the pattern, the oxide layer, the removable dielectric layer, and the substrate to form a plurality of intersecting trenches in the substrate; and
filling the plurality of intersecting trenches to form a deep trench isolation (DTI) structure in the substrate.