US 12,068,168 B2
Processes for reducing line-end spacing
Wen-Yen Chen, Chu Tung Township (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on May 24, 2022, as Appl. No. 17/664,732.
Claims priority of provisional application 63/268,179, filed on Feb. 17, 2022.
Prior Publication US 2023/0260795 A1, Aug. 17, 2023
Int. Cl. H01L 21/308 (2006.01); H01L 21/033 (2006.01); H01L 21/306 (2006.01); H01L 21/311 (2006.01); H01L 21/3213 (2006.01); H01L 21/768 (2006.01)
CPC H01L 21/3086 (2013.01) [H01L 21/0332 (2013.01); H01L 21/0337 (2013.01); H01L 21/0338 (2013.01); H01L 21/30604 (2013.01); H01L 21/3088 (2013.01); H01L 21/31116 (2013.01); H01L 21/31144 (2013.01); H01L 21/32139 (2013.01); H01L 21/76802 (2013.01); H01L 21/76811 (2013.01); H01L 21/76813 (2013.01); H01L 21/76816 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
forming a first etching mask to cover a mandrel, a first spacer, and a second spacer, wherein the first spacer and the second spacer are in contact with opposing sidewalls of the mandrel;
patterning the first etching mask, wherein after the patterning, the first etching mask comprises:
a first portion covering the first spacer;
a second portion covering the second spacer; and
a bridge portion connecting the first portion to the second portion, wherein the bridge portion comprises first sidewalls;
performing a first etching process on the mandrel using the first etching mask to define pattern, wherein after the first etching process, the mandrel comprises a second bridge portion having second sidewalls vertically aligned to corresponding ones of the first sidewalls; and
after the mandrel is etched-through, performing a second etching process to laterally recess the second bridge portion of the mandrel.