Apparatus, methods and are disclosed for measuring refractive index of an absorber material used in EUV phase shift masks. The method and apparatus utilize a reference measurement and as series of reflectance measurements at a range of EUV wavelengths and thickness values for the absorber material to determine the refractive index of the absorber material.

Apparatus, methods and are disclosed for measuring refractive index of an absorber material used in EUV phase shift masks. The method and apparatus utilize a reference measurement and as series of reflectance measurements at a range of EUV wavelengths and thickness values for the absorber material to determine the refractive index of the absorber material.

Methods for removing haze defects from a photomask or reticle are disclosed. The photomask is placed into a chamber which includes a hydrogen atmosphere. The photomask is then exposed to radiation. The energy from the radiation, together with the hydrogen, causes decomposition of the haze defects. The methods can be practiced on-site and quickly, without the need for wet chemicals or the need to remove the pellicle before cleaning of the photomask. A device for conducting the methods is also disclosed herein.

Methods for removing haze defects from a photomask or reticle are disclosed. The photomask is placed into a chamber which includes a hydrogen atmosphere. The photomask is then exposed to radiation. The energy from the radiation, together with the hydrogen, causes decomposition of the haze defects. The methods can be practiced on-site and quickly, without the need for wet chemicals or the need to remove the pellicle before cleaning of the photomask. A device for conducting the methods is also disclosed herein.

A mask blank includes a substrate and a thin film formed on the substrate, the thin film including hafnium and oxygen. A total content of hafnium and oxygen of the thin film is 95 atom % or more. An oxygen content of the thin film is 60 atom % or more. An X-ray diffraction profile of a diffraction angle 2θ between 25 degrees and 35 degrees has a maximum diffraction intensity in a diffraction angle 2θ between 28 degrees and 29 degrees, the X-ray diffraction profile being obtained by an X-ray diffraction analysis with an Out-of-Plane measurement with respect to the thin film.

A photomask blank having a substrate; and a multilayer film including a first layer, a second layer, and a third layer. The first layer contains 43 at % or less chromium, 32 at % or more oxygen, 25 at % or less nitrogen and 5 at % or more and 18 at % or less carbon and has a thickness of 8 nm or more and 16 nm or less. The second layer contains 66 at % or more and 92 at % or less chromium and 8 at % or more and 30 at % or less nitrogen and has a thickness of 50 nm or more and 75 nm or less. The third layer contains 44 at % or less chromium, 30 at % or more oxygen and 28 at % or less nitrogen and has a thickness of 10 nm or less. A surface roughness Rq of the multilayer film is 0.65 nm or less.

Provided is a phase shift mask blank including a substrate, and a phase shift film thereon, the phase shift film composed of a material containing silicon and nitrogen and free of a transition metal, exposure light being KrF excimer laser, the phase shift film consisting of a single layer or a plurality of layers, the single layer or each of the plurality of layers having a refractive index n of at least 2.5 and an extinction coefficient k of 0.4 to 1, with respect to the exposure light, and the phase shift film having a phase shift of 170 to 190° and a transmittance of 4 to 8%, with respect to the exposure light, and a thickness of up to 85 nm.

Provided is a phase shift mask blank including a substrate, and a phase shift film thereon, the phase shift film composed of a material containing silicon and nitrogen and free of a transition metal, exposure light being KrF excimer laser, the phase shift film consisting of a single layer or a plurality of layers, the single layer or each of the plurality of layers having a refractive index n of at least 2.5 and an extinction coefficient k of 0.4 to 1, with respect to the exposure light, and the phase shift film having a phase shift of 170 to 190° and a transmittance of 4 to 8%, with respect to the exposure light, and a thickness of up to 85 nm.

A halftone phase shift-type photomask blank including a transparent substrate, and a halftone phase shift film formed on the substrate, and including at least one layer composed of silicon, nitrogen and oxygen is provided. The halftone phase shift film has a phase shift of at least 150° and up to 200° and a transmittance of at least 20%, with respect to exposure light having a wavelength of up to 200 nm, and a film surface having a surface roughness RMS of up to 0.8 nm, and an in-plane variation of transmittance calculated from the maximum transmittance T.sub.max and the minimum transmittance T.sub.min within a mask pattern forming area by the expression: (T.sub.max−T.sub.min)/(T.sub.max+T.sub.min)×100 is up to 2%.

Methods of inspecting photomasks are provided. A method of inspecting a photomask includes electronically inspecting a first mask pattern in a mask region of the photomask and refraining from electronically inspecting a separate second mask pattern in the mask region of the photomask. The first mask pattern includes a geometric feature that corresponds to at least a portion of the second mask pattern. Moreover, the mask region is outside of a scribe lane region of the photomask. Related methods of manufacturing photomasks and methods of manufacturing semiconductor devices are also provided.