A mask blank including a light shielding film pattern having high ArF light fastness.

The light shielding film is on a transparent substrate. In the mask blank, the light shielding film is a single layer film formed of a material containing silicon and nitrogen, and the light shielding film has an optical density to an ArF excimer laser exposure light of 2.5 or more, a surface reflectance to the exposure light of 40% or less, a back-surface reflectance to the exposure light of 40% or less, a transmittance to a light having a wavelength of 900 nm of 50% or less, an extinction coefficient to a light having a wavelength of 900 nm of 0.04 or more, and a thickness of 60 nm or less.

Metrology methods and targets are provided for reducing or eliminating a difference between a device pattern position and a target pattern position while maintaining target printability, process compatibility and optical contrast—in both imaging and scatterometry metrology. Pattern placement discrepancies may be reduced by using sub-resolved assist features in the mask design which have a same periodicity (fine pitch) as the periodic structure and/or by calibrating the measurement results using PPE (pattern placement error) correction factors derived by applying learning procedures to specific calibration terms, in measurements and/or simulations. Metrology targets are disclosed with multiple periodic structures at the same layer (in addition to regular target structures), e.g., in one or two layers, which are used to calibrate and remove PPE, especially when related to asymmetric effects such as scanner aberrations, off-axis illumination and other error sources.

Metrology methods and targets are provided for reducing or eliminating a difference between a device pattern position and a target pattern position while maintaining target printability, process compatibility and optical contrast—in both imaging and scatterometry metrology. Pattern placement discrepancies may be reduced by using sub-resolved assist features in the mask design which have a same periodicity (fine pitch) as the periodic structure and/or by calibrating the measurement results using PPE (pattern placement error) correction factors derived by applying learning procedures to specific calibration terms, in measurements and/or simulations. Metrology targets are disclosed with multiple periodic structures at the same layer (in addition to regular target structures), e.g., in one or two layers, which are used to calibrate and remove PPE, especially when related to asymmetric effects such as scanner aberrations, off-axis illumination and other error sources.

The present disclosure provides masks suitable for Extreme Ultraviolet (EUV) and X-ray lithography by including a non-reflective region combined with a reflective multilayer. This non-reflective region replaces a typical absorber layer used to provide the pattern for integrated circuits.

The present disclosure provides masks suitable for Extreme Ultraviolet (EUV) and X-ray lithography by including a non-reflective region combined with a reflective multilayer. This non-reflective region replaces a typical absorber layer used to provide the pattern for integrated circuits.

Disclosed is a blank mask including a transparent substrate and a light shielding film disposed on the transparent substrate, wherein the light shielding film includes a transition metal and at least one selected from the group consisting of oxygen and nitrogen, wherein when a surface of the light shielding film includes nine sectors formed by trisecting the surface of the light shielding film vertically and horizontally, each of the nine sectors has a Rsk value, respectively, and an average value of the Rsk values of the nine sectors is equal to −0.64 or more and less than or equal to 0, where Rsk value is a height symmetry of the surface of the light shielding film measured in accordance with ISO_4287, and wherein an average value of Rku values, which are kurtosis of the surface of the light shielding film measured in accordance with ISO_4287, of the nine sectors is 3 or less.

Disclosed is a blank mask including a transparent substrate and a light shielding film disposed on the transparent substrate, wherein the light shielding film includes a transition metal and at least one selected from the group consisting of oxygen and nitrogen, wherein when a surface of the light shielding film includes nine sectors formed by trisecting the surface of the light shielding film vertically and horizontally, each of the nine sectors has a Rsk value, respectively, and an average value of the Rsk values of the nine sectors is equal to −0.64 or more and less than or equal to 0, where Rsk value is a height symmetry of the surface of the light shielding film measured in accordance with ISO_4287, and wherein an average value of Rku values, which are kurtosis of the surface of the light shielding film measured in accordance with ISO_4287, of the nine sectors is 3 or less.

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.

Provided is a mask blank including a phase shift film.

The mask blank includes a phase shift film on a main surface of a transparent substrate, the phase shift film contains silicon, oxygen, and nitrogen, a ratio of a nitrogen content [atom %] to a silicon content [atom %] in the phase shift film is 0.20 or more and 0.52 or less, a ratio of an oxygen content [atom %] to a silicon content [atom %] in the phase shift film is 1.16 or more and 1.70 or less, a refractive index n of the phase shift film to a wavelength of an exposure light of an ArF excimer laser is 1.7 or more and 2.0 or less, and an extinction coefficient k is 0.05 or less.