Provided are a reflective mask blank, having a phase shift film having little dependence of phase difference and reflectance on film thickness, and a reflective mask. The reflective mask blank is characterized in that the phase shift film is composed of a material comprised of an alloy having two or more types of metal so that reflectance of the surface of the phase shift film is more than 3% to not more than 20% and so as to have a phase difference of 170 degrees to 190 degrees, and when a group of metal elements that satisfies the refractive index n and the extinction coefficient k of k>α*n+β is defined as Group A and a group of metal elements that satisfies the refractive index n and the extinction coefficient k of k<α*n+β is defined as Group B, the alloy is such that the composition ratio is adjusted so that the amount of change in the phase difference is within the range of ±2 degrees and the amount of change in reflectance is within the range of ±0.2% when one or more types of metal element each is selected from the Group A and the Group B and the film thickness of the phase shift film has fluctuated by ±0.5% with respect to a set film thickness (provided that α: proportional constant, β: constant).

Provided are a reflective mask blank, having a phase shift film having little dependence of phase difference and reflectance on film thickness, and a reflective mask. The reflective mask blank is characterized in that the phase shift film is composed of a material comprised of an alloy having two or more types of metal so that reflectance of the surface of the phase shift film is more than 3% to not more than 20% and so as to have a phase difference of 170 degrees to 190 degrees, and when a group of metal elements that satisfies the refractive index n and the extinction coefficient k of k>α*n+β is defined as Group A and a group of metal elements that satisfies the refractive index n and the extinction coefficient k of k<α*n+β is defined as Group B, the alloy is such that the composition ratio is adjusted so that the amount of change in the phase difference is within the range of ±2 degrees and the amount of change in reflectance is within the range of ±0.2% when one or more types of metal element each is selected from the Group A and the Group B and the film thickness of the phase shift film has fluctuated by ±0.5% with respect to a set film thickness (provided that α: proportional constant, β: constant).

Provided is a reflective mask blank.

The reflective mask blank has a multilayer reflective film and a thin film for pattern formation in this order on a main surface of a substrate; the thin film consists of a single layer structure consisting of a ruthenium-containing layer at least containing ruthenium, nitrogen, and oxygen or a multilayer structure including the ruthenium-containing layer; and when the ruthenium-containing layer is subjected to an analysis by an In-Plane measurement of an X-ray diffraction method to obtain an X-ray diffraction profile where, provided I_P1 is the maximum value of diffraction intensity within a diffraction angle 2θ ranging from 65 degrees to 75 degrees and I_avg is the average value of diffraction intensity within a diffraction angle 2θ ranging from 55 degrees to 65 degrees, I_P1/I_avg is greater than 1.0 and less than 3.0.

Provided is a mask blank (100) for manufacturing a phase shift mask, the mask blank enabling formation of a high-precision and fine pattern on a light shielding film. The mask blank (100) in which a phase shift film (2) made of a material containing silicon, a light shielding film (3) made of a material containing chromium, oxygen, and carbon, and a hard mask film (4) made of a material containing one or more elements selected from silicon and tantalum are provided in this order on a transparent substrate (1) is characterized in that the light shielding film (3) is a single layer film having a composition gradient portion with an increased oxygen content at a surface on the hard mask film (4) side and in a region close thereto, the light shielding film (3) has a maximum peak of N1s narrow spectrum obtained by analysis of X-ray photoelectron spectroscopy of lower detection limit or less, and a part of the light shielding film (3) excluding the composition gradient portion has a chromium content of 50 atom % or more and has a maximum peak of Cr2p narrow spectrum obtained by analysis of X-ray photoelectron spectroscopy at binding energy of 574 eV or less.

Provided is a mask blank (100) for manufacturing a phase shift mask, the mask blank enabling formation of a high-precision and fine pattern on a light shielding film. The mask blank (100) in which a phase shift film (2) made of a material containing silicon, a light shielding film (3) made of a material containing chromium, oxygen, and carbon, and a hard mask film (4) made of a material containing one or more elements selected from silicon and tantalum are provided in this order on a transparent substrate (1) is characterized in that the light shielding film (3) is a single layer film having a composition gradient portion with an increased oxygen content at a surface on the hard mask film (4) side and in a region close thereto, the light shielding film (3) has a maximum peak of N1s narrow spectrum obtained by analysis of X-ray photoelectron spectroscopy of lower detection limit or less, and a part of the light shielding film (3) excluding the composition gradient portion has a chromium content of 50 atom % or more and has a maximum peak of Cr2p narrow spectrum obtained by analysis of X-ray photoelectron spectroscopy at binding energy of 574 eV or less.

A patterning process is performed on a semiconductor wafer coated with a bottom layer, a middle layer and a photoresist layer having a starting thickness. The patterning process includes: performing an exposure step including exposing the semiconductor wafer using a mask that includes a feature which produces an intermediate light exposure in a target area followed by processing that creates openings in the photoresist layer in accordance with the mask and thins the photoresist in the target area due to the intermediate light exposure in the target area leaving thinned photoresist in the target area; performing middle layer etching to form openings in the middle layer aligned with the openings in the photoresist layer, wherein the middle layer etching does not remove the middle layer in the target area due to protection provided by the thinned photoresist; and performing trim etching to trim the middle layer in the target area.

A patterning process is performed on a semiconductor wafer coated with a bottom layer, a middle layer and a photoresist layer having a starting thickness. The patterning process includes: performing an exposure step including exposing the semiconductor wafer using a mask that includes a feature which produces an intermediate light exposure in a target area followed by processing that creates openings in the photoresist layer in accordance with the mask and thins the photoresist in the target area due to the intermediate light exposure in the target area leaving thinned photoresist in the target area; performing middle layer etching to form openings in the middle layer aligned with the openings in the photoresist layer, wherein the middle layer etching does not remove the middle layer in the target area due to protection provided by the thinned photoresist; and performing trim etching to trim the middle layer in the target area.

A mask includes a substrate, a reflective multilayer, an absorption layer and an absorption part. The substrate includes a mask image region and a mask frame region, wherein the mask frame region has a mask black border region adjacent to the mask image region. The reflective multilayer is disposed over the substrate. The absorption layer is disposed over the reflective multilayer. The absorption part is disposed in the reflective multilayer and the absorption layer and in the mask black border region, wherein an entire top surface of the absorption part is substantially flush with a top surface of the absorption layer.

A mask includes a substrate, a reflective multilayer, an absorption layer and an absorption part. The substrate includes a mask image region and a mask frame region, wherein the mask frame region has a mask black border region adjacent to the mask image region. The reflective multilayer is disposed over the substrate. The absorption layer is disposed over the reflective multilayer. The absorption part is disposed in the reflective multilayer and the absorption layer and in the mask black border region, wherein an entire top surface of the absorption part is substantially flush with a top surface of the absorption layer.

In one embodiment, this hard mask for plasma etching is formed on a silicon-containing film. The hard mask is an amorphous film, and contains tungsten and silicon. The ratio of the concentration of tungsten and the concentration of silicon in the surface of the hard mask can be within the range between a ratio specifying that the concentration of tungsten is 35 at % and the concentration of silicon is 65 at % and a ratio specifying that the concentration of tungsten is 50 at % and the concentration of silicon is 50 at %.