US 12,444,645 B2
Etch profile control of isolation trench
Hsien-Chung Huang, Hsinchu (TW); Chiung-Wen Hsu, Tainan (TW); Mei-Ju Kuo, Hsinchu (TW); Yu-Ting Weng, Taichung (TW); Yu-Chi Lin, Hsinchu County (TW); Ting-Chung Wang, Kaohsiung (TW); and Chao-Cheng Chen, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed on Jun. 12, 2024, as Appl. No. 18/741,166.
Application 18/741,166 is a continuation of application No. 17/371,618, filed on Jul. 9, 2021, granted, now 12,040,219.
Claims priority of provisional application 63/163,232, filed on Mar. 19, 2021.
Prior Publication US 2024/0332062 A1, Oct. 3, 2024
Int. Cl. H01L 21/762 (2006.01); H01L 21/02 (2006.01); H01L 21/3065 (2006.01); H01L 21/308 (2006.01); H01L 21/8238 (2006.01); H01L 27/092 (2006.01); H01L 29/06 (2006.01); H01L 29/423 (2006.01); H01L 29/66 (2006.01); H01L 29/78 (2006.01); H01L 29/786 (2006.01); H10D 30/01 (2025.01); H10D 30/62 (2025.01); H10D 30/67 (2025.01); H10D 62/10 (2025.01); H10D 64/01 (2025.01); H10D 84/01 (2025.01); H10D 84/03 (2025.01); H10D 84/85 (2025.01)
CPC H01L 21/76232 (2013.01) [H01L 21/0259 (2013.01); H01L 21/3065 (2013.01); H01L 21/308 (2013.01); H10D 30/024 (2025.01); H10D 30/031 (2025.01); H10D 30/6211 (2025.01); H10D 30/6735 (2025.01); H10D 30/6757 (2025.01); H10D 62/118 (2025.01); H10D 64/017 (2025.01); H10D 64/018 (2025.01); H10D 84/0167 (2025.01); H10D 84/017 (2025.01); H10D 84/0188 (2025.01); H10D 84/0193 (2025.01); H10D 84/038 (2025.01); H10D 84/853 (2025.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
forming a first semiconductor layer over a n-type region of a substrate;
forming a second semiconductor layer over a p-type region of the substrate;
performing a first etching process to the first and second semiconductor layers to form a first trench, wherein the first trench has a first inclined surface across an interface between the first and second semiconductor layers;
performing a second etching process to deepen the first trench into a second trench in the substrate, wherein the second trench has a second inclined surface across a boundary between the n-type region and the p-type region;
forming an isolation structure in the second trench; and
forming a gate structure over the isolation structure.