US 12,178,032 B2
Source/drain feature separation structure
Wen-Chun Keng, Hsinchu County (TW); Kuo-Hsiu Hsu, Taoyuan County (TW); Chih-Chuan Yang, Hsinchu (TW); Lien Jung Hung, Taipei (TW); and Ping-Wei Wang, Hsin-Chu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Jul. 22, 2022, as Appl. No. 17/814,279.
Application 17/814,279 is a division of application No. 16/915,609, filed on Jun. 29, 2020, granted, now 11,637,109.
Prior Publication US 2022/0367482 A1, Nov. 17, 2022
Int. Cl. H01L 21/02 (2006.01); H01L 21/764 (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 29/786 (2006.01); H10B 10/00 (2023.01)
CPC H10B 10/125 (2023.02) [H01L 21/02126 (2013.01); H01L 21/02167 (2013.01); H01L 21/02178 (2013.01); H01L 21/02181 (2013.01); H01L 21/02183 (2013.01); H01L 21/02186 (2013.01); H01L 21/02189 (2013.01); H01L 21/02532 (2013.01); H01L 21/02603 (2013.01); H01L 21/764 (2013.01); H01L 21/823807 (2013.01); H01L 21/823814 (2013.01); H01L 21/823878 (2013.01); H01L 27/092 (2013.01); H01L 29/0653 (2013.01); H01L 29/0673 (2013.01); H01L 29/42392 (2013.01); H01L 29/66545 (2013.01); H01L 29/66742 (2013.01); H01L 29/78618 (2013.01); H01L 29/78696 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
receiving a workpiece comprising:
a substrate, and
a stack disposed over the substrate and comprising a plurality of channel layers interleaved by a plurality of sacrificial layers;
patterning the stack and a portion of the substrate to form a first fin-shaped structure, a second fin-shaped structure and a third fin-shaped structure, wherein the first fin-shaped structure and the second fin-shaped structure are spaced apart by a first spacing, and the second fin-shaped structure and the third fin-shaped structure are spaced apart by a second spacing smaller than the first spacing;
forming an isolation feature between the first fin-shaped structure and the second fin-shaped structure and between the second fin-shaped structure and the third fin-shaped structure;
after the forming of the isolation feature, depositing a cladding layer over the first fin-shaped structure, the second fin-shaped structure and the third fin-shaped structure;
depositing a first dielectric layer over the workpiece;
depositing a second dielectric layer over the first dielectric layer, wherein the second spacing prevents the second dielectric layer from entering between the second fin-shaped structure and the third fin-shaped structure;
after the depositing of the second dielectric layer, planarizing the workpiece;
after the planarizing, selectively recessing the first dielectric layer and the second dielectric layer to form a first recess between the first fin-shaped structure and the second fin-shaped structure and a second recess between the second fin-shaped structure and the third fin-shaped structure, wherein the first recess is deeper than the second recess;
after the selectively recessing, selectively etching back the first dielectric layer disposed between the second fin-shaped structure and the third fin-shaped structure; and
after the selectively etching back, depositing a capping layer over the workpiece.