A mirror for extreme ultraviolet light includes: a substrate (41); a multilayer film (42) provided on the substrate and configured to reflect extreme ultraviolet light; and a capping layer (53) provided on the multilayer film, and the capping layer includes a first layer (61) containing an oxide of a metal, and a second layer (62) arranged between the first layer and the multilayer film and containing at least one of a boride of the metal and a nitride of the metal.

A reflective mask includes a substrate, a lower reflective multilayer disposed over the substrate, an intermediate layer disposed over the lower reflective multilayer, an upper reflective multilayer disposed over the intermediate layer, a capping layer disposed over the upper reflective multilayer, and an absorber layer disposed in a trench formed in the upper reflective layers and over the intermediate layer. The intermediate layer includes a metal other than Cr, Ru, Si, Si compound and carbon.

A reflective mask includes a substrate, a lower reflective multilayer disposed over the substrate, an intermediate layer disposed over the lower reflective multilayer, an upper reflective multilayer disposed over the intermediate layer, a capping layer disposed over the upper reflective multilayer, and an absorber layer disposed in a trench formed in the upper reflective layers and over the intermediate layer. The intermediate layer includes a metal other than Cr, Ru, Si, Si compound and carbon.

A method includes: receiving a photomask; patterning a wafer by directing a first radiation beam to the wafer through the photomask at a first tilt angle; and inspecting the photomask. The inspecting includes: directing a second radiation beam to the photomask at a second tilt angle greater than the first tilt angle; receiving a third radiation beam reflected from the photomask; and generating an image of the photomask according to the third radiation beam.

An extreme ultraviolet mask, comprising an absorber having an index of refraction ranging from 0.87 to 1.02, an extinction coefficient ranging from 0.065 to 0.085, and a thickness ranging from 33.5 nm to 43.5 nm.

An extreme ultraviolet mask, comprising an absorber having an index of refraction ranging from 0.87 to 1.02, an extinction coefficient ranging from 0.065 to 0.085, and a thickness ranging from 33.5 nm to 43.5 nm.

Provided is a reflective mask blank with which it is possible to further reduce the shadowing effect of a reflective mask, and also possible to form a fine and highly accurate phase-shift pattern. A reflective mask blank having, in the following order on a substrate, a multilayer reflective film and a phase-shift film that shifts the phase of EUV light, said reflective mask blank characterized in that: the phase-shift film has a first layer and a second layer; the first layer comprises a material that contains at least one element from among tantalum (Ta) and chromium (Cr); and the second layer comprises a metal-containing material that contains ruthenium (Ru) and at least one element from among chromium (Cr), nickel (Ni), cobalt (Co), vanadium (V), niobium (Nb), molybdenum (Mo), tungsten (W), and rhenium (Re).

Provided is a reflective mask blank with which it is possible to further reduce the shadowing effect of a reflective mask, and also possible to form a fine and highly accurate phase-shift pattern. A reflective mask blank having, in the following order on a substrate, a multilayer reflective film and a phase-shift film that shifts the phase of EUV light, said reflective mask blank characterized in that: the phase-shift film has a first layer and a second layer; the first layer comprises a material that contains at least one element from among tantalum (Ta) and chromium (Cr); and the second layer comprises a metal-containing material that contains ruthenium (Ru) and at least one element from among chromium (Cr), nickel (Ni), cobalt (Co), vanadium (V), niobium (Nb), molybdenum (Mo), tungsten (W), and rhenium (Re).

Phase shift masks for an extreme ultraviolet lithography process includes a substrate, a reflection layer on the substrate, a capping layer on the reflection layer, and phase shift patterns on the capping layer. Each of the phase shift patterns may include a lower absorption pattern on the capping layer and an upper absorption pattern on the lower absorption pattern. A refractive index of the upper absorption pattern may be higher than a refractive index of the lower absorption pattern, and a thickness of the upper absorption pattern is smaller than a thickness of the lower absorption pattern.

Phase shift masks for an extreme ultraviolet lithography process includes a substrate, a reflection layer on the substrate, a capping layer on the reflection layer, and phase shift patterns on the capping layer. Each of the phase shift patterns may include a lower absorption pattern on the capping layer and an upper absorption pattern on the lower absorption pattern. A refractive index of the upper absorption pattern may be higher than a refractive index of the lower absorption pattern, and a thickness of the upper absorption pattern is smaller than a thickness of the lower absorption pattern.