US 11,809,075 B2
EUV lithography mask with a porous reflective multilayer structure
Chih-Tsung Shih, Hsinchu (TW); Shih-Chang Shih, Hsinchu (TW); Li-Jui Chen, Hsinchu (TW); and Po-Chung Cheng, Chiayi County (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Aug. 4, 2021, as Appl. No. 17/394,005.
Application 17/394,005 is a continuation of application No. 15/798,937, filed on Oct. 31, 2017, granted, now 11,086,209.
Claims priority of provisional application 62/490,874, filed on Apr. 27, 2017.
Prior Publication US 2021/0364907 A1, Nov. 25, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. G03F 1/24 (2012.01); G03F 1/52 (2012.01); G03F 1/80 (2012.01); G03F 1/54 (2012.01)
CPC G03F 1/24 (2013.01) [G03F 1/52 (2013.01); G03F 1/54 (2013.01); G03F 1/80 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A lithography mask, comprising:
a substrate;
a first layer of a reflective structure disposed over the substrate; and
a second layer of the reflective structure disposed over the first layer;
wherein:
the first layer and the second layer have different material compositions;
the second layer includes a plurality of segments that are within the second layer, the segments being separated from one another by a plurality of gaps; and
at least some of the segments of the second layer each has a slanted sidewall.