	US 11,815,806 B2
	Reflective mask blank, reflective mask and manufacturing method thereof, and semiconductor device manufacturing method
Yohei Ikebe, Tokyo (JP); and Tsutomu Shoki, Tokyo (JP)
Assigned to HOYA CORPORATION, Tokyo (JP)
Filed by HOYA CORPORATION, Tokyo (JP)
Filed on Nov. 18, 2022, as Appl. No. 17/990,049.
Application 17/990,049 is a continuation of application No. 17/056,713, granted, now 11,531,264, previously published as PCT/JP2019/020632, filed on May 24, 2019.
Claims priority of application No. 2018-100362 (JP), filed on May 25, 2018; and application No. 2018-165247 (JP), filed on Sep. 4, 2018.
Prior Publication US 2023/0168575 A1, Jun. 1, 2023
Int. Cl. G03F 1/32 (2012.01); G03F 1/24 (2012.01); G03F 7/20 (2006.01)

CPC G03F 1/32 (2013.01) [G03F 1/24 (2013.01); G03F 7/2004 (2013.01)]

21 Claims

1. A reflective mask blank comprising:

a substrate;

a multilayer reflective film on the substrate; and

a phase shift film on the multilayer reflective film,

wherein the phase shift film comprises ruthenium (Ru) and at least one selected from cobalt (Co), titanium (Ti), niobium (Nb), molybdenum (Mo) and rhenium (Re),

when the phase shift film comprises Co, a composition ratio of the Ru and the Co (Ru:Co) is 20:1 to 1:5,

when the phase shift film comprises Ti, a composition ratio of the Ru and the Ti (Ru:Ti) is 20:1 to 1:20,

when the phase shift film comprises Nb, a composition ratio of the Ru and the Nb (Ru:Nb) is 20:1 to 5:1,

when the phase shift film comprises Mo, a composition ratio of the Ru and the Mo (Ru:Mo) is 20:1 to 4:1, and

when the phase shift film comprises Re, a composition ratio of the Ru and the Re (Ru:Re) is 20:1 to 1:20.