US 12,326,656 B2
Mask blank and method of manufacturing photomask
Hitoshi Maeda, Tokyo (JP); Kazutake Taniguchi, Tokyo (JP); Kazuaki Matsui, Tokyo (JP); and Naoto Yonemaru, Tokyo (JP)
Assigned to HOYA CORPORATION, Tokyo (JP); and TEKSCEND PHOTOMASK CORP., Tokyo (JP)
Appl. No. 17/799,573
Filed by HOYA CORPORATION, Tokyo (JP); and TEKSCEND PHOTOMASK CORP., Tokyo (JP)
PCT Filed Feb. 16, 2021, PCT No. PCT/JP2021/005627
§ 371(c)(1), (2) Date Aug. 12, 2022,
PCT Pub. No. WO2021/192734, PCT Pub. Date Sep. 30, 2021.
Claims priority of application No. 2020-050946 (JP), filed on Mar. 23, 2020.
Prior Publication US 2023/0069092 A1, Mar. 2, 2023
Int. Cl. G03F 1/32 (2012.01); G03F 1/50 (2012.01); G03F 1/54 (2012.01); G03F 1/80 (2012.01); H01L 21/3065 (2006.01)
CPC G03F 1/32 (2013.01) [G03F 1/50 (2013.01); G03F 1/54 (2013.01); G03F 1/80 (2013.01); H01L 21/3065 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A mask blank having a structure where a thin film for pattern formation and a hard mask film are stacked in this order on a transparent substrate,
wherein the thin film is formed of a material containing chromium,
wherein the hard mask film has a stacked structure of a lower layer and an upper layer,
wherein the lower layer is formed of a material containing silicon and oxygen,
wherein the upper layer is formed of a material containing tantalum and oxygen and containing the oxygen of 30 atom % or more, and
wherein a ratio of a thickness of the upper layer relative to a total thickness of the hard mask film is 0.7 or less.