Provided is a mask blank including an etching stopper film. The mask blank has a structure where an etching stopper film and a thin film for pattern formation are stacked in this order on a transparent substrate, featured in that the thin film includes a material containing silicon, the etching stopper film includes a material containing hafnium, aluminum, and oxygen, and a ratio by atom % of an amount of hafnium to a total amount of hafnium and aluminum in the etching stopper film is 0.86 or less.

Provided is a mask blank including an etching stopper film. The mask blank has a structure where an etching stopper film and a thin film for pattern formation are stacked in this order on a transparent substrate, featured in that the thin film includes a material containing silicon, the etching stopper film includes a material containing hafnium, aluminum, and oxygen, and a ratio by atom % of an amount of hafnium to a total amount of hafnium and aluminum in the etching stopper film is 0.86 or less.

Provided is a mask blank including an etching stopper. The mask blank has a structure where an etching stopper film and a thin film for pattern formation are stacked in this order on a transparent substrate, in which the thin film is formed of a material containing silicon, the etching stopper film is formed of a material containing hafnium, aluminum, and oxygen, and an oxygen deficiency ratio of the etching stopper film is 6.4% or less.

A phase-shift mask for extreme ultraviolet (EUV) lithography may be provided. The phase-shift mask may include a substrate, a reflection layer on the substrate, and phase-shift patterns including at least one metal nitride on the reflection layer. The at least one metal nitride may include at least one of TaN, TiN, ZrN, HfN, CrN, VN, NbN, MoN, WN, AlN, GaN, ScN, and YN.

A phase-shift mask for extreme ultraviolet (EUV) lithography may be provided. The phase-shift mask may include a substrate, a reflection layer on the substrate, and phase-shift patterns including at least one metal nitride on the reflection layer. The at least one metal nitride may include at least one of TaN, TiN, ZrN, HfN, CrN, VN, NbN, MoN, WN, AlN, GaN, ScN, and YN.

Provided is a mask blank for a phase shift mask including an etching stopper film. The mask blank has a structure where a transparent substrate has stacked thereon an etching stopper film and a phase shift film in this order, in which the phase shift film contains silicon and oxygen, in which the phase shift film has a refractive index n.sub.1 of 1.5 or more for light of 193 nm wavelength and an extinction coefficient k.sub.1 of 0.1 or less for light of 193 nm wavelength, in which the etching stopper film has a refractive index n.sub.2 of 2.5 or more and 3.1 or less for light of 193 nm wavelength and an extinction coefficient k.sub.2 of 0.4 or less for light of 193 nm wavelength, and the refractive index n.sub.2 and the extinction coefficient k.sub.2 satisfy at least one of a set of specified conditions.

Provided is a mask blank for a phase shift mask including an etching stopper film. The mask blank has a structure where a transparent substrate has stacked thereon an etching stopper film and a phase shift film in this order, in which the phase shift film contains silicon and oxygen, in which the phase shift film has a refractive index n.sub.1 of 1.5 or more for light of 193 nm wavelength and an extinction coefficient k.sub.1 of 0.1 or less for light of 193 nm wavelength, in which the etching stopper film has a refractive index n.sub.2 of 2.5 or more and 3.1 or less for light of 193 nm wavelength and an extinction coefficient k.sub.2 of 0.4 or less for light of 193 nm wavelength, and the refractive index n.sub.2 and the extinction coefficient k.sub.2 satisfy at least one of a set of specified conditions.

The present disclosure provides a mask. The mask includes a substrate; an etch stop layer disposed on the substrate, wherein the etch stop layer includes at least one of ruthenium oxide, tungsten nitride, and titanium nitride and is doped with at least one of phosphorous (P), calcium (Ca), and sodium (Na); and a material layer disposed on the etch stop layer and patterned to have an opening, wherein the etch stop layer completely covers a portion of the substrate within the opening.

The present disclosure provides a mask. The mask includes a substrate; an etch stop layer disposed on the substrate, wherein the etch stop layer includes at least one of ruthenium oxide, tungsten nitride, and titanium nitride and is doped with at least one of phosphorous (P), calcium (Ca), and sodium (Na); and a material layer disposed on the etch stop layer and patterned to have an opening, wherein the etch stop layer completely covers a portion of the substrate within the opening.

Provided is a mask blank for a phase shift mask including an etching stopper film. A mask blank has a structure where a transparent substrate has layered thereon an etching stopper film and a phase shift film in this order, in which the phase shift film contains silicon and oxygen, in which the phase shift film has a refractive index n.sub.1 of 1.5 or more for light of 193 nm wavelength and an extinction coefficient k.sub.1 of 0.1 or less for light of 193 nm wavelength, in which the etching stopper film has a refractive index n.sub.2 of 2.6 or more for light of 193 nm wavelength and an extinction coefficient k.sub.2 of 0.4 or less for light of 193 nm wavelength, and the refractive index n.sub.2 and the extinction coefficient k.sub.2 satisfy at least one of k.sub.2≤[(−0.188×n.sub.2)+0.879] and k.sub.2≤[(2.75×n.sub.2)−6.945].