A laminate for a blank mask includes a light-transmitting layer; a phase shift film disposed on the light-transmitting layer; and residual ions measured from a surface of the phase shift film through ion chromatography comprises at least one of sulfate ions in a concentration of 0 ng/cm.sup.2 to 0.05 ng/cm.sup.2, nitric oxide ions in a concentration of 0 ng/cm.sup.2 to 0.5 ng/cm.sup.2, or ammonium ions in a concentration of 0 ng/cm.sup.2 to 5 ng/cm.sup.2, or any combination thereof. A sum of concentrations of the residual ions is more than 0.

A method including forming an insulating film over first, second, third and fourth regions of a semiconductor substrate; forming a polyimide film on the insulating film; and patterning the polyimide film with a lithography method using a photomask including at least a first region of a first transmittance rate, a second region of a second transmittance rate, a third region. having a shading material, and a fourth region, wherein the first, second, third and fourth regions of the photomask correspond to the first, second, third and fourth regions of the semiconductor substrate, respectively.

A mask blank with phase shift film where changes in transmittance and phase shift to an exposure light of an ArF excimer laser are suppressed. The film transmits light of an ArF excimer laser at a transmittance of 2% or more and less than 10% and generates a phase difference of 150 degrees or more and 190 degrees or less between the exposure light transmitted through the phase shift film and the exposure light transmitted through the air for the same distance as a thickness of the phase shift film. The film has a stacked lower layer and upper layer, the lower layer containing metal and silicon and substantially free of oxygen. The upper layer containing metal, silicon, nitrogen, and oxygen. The lower layer is thinner than the upper layer, and the ratio of metal to metal and silicon of the upper layer is less than the lower layer.

A mask blank with phase shift film where changes in transmittance and phase shift to an exposure light of an ArF excimer laser are suppressed. The film transmits light of an ArF excimer laser at a transmittance of 2% or more and less than 10% and generates a phase difference of 150 degrees or more and 190 degrees or less between the exposure light transmitted through the phase shift film and the exposure light transmitted through the air for the same distance as a thickness of the phase shift film. The film has a stacked lower layer and upper layer, the lower layer containing metal and silicon and substantially free of oxygen. The upper layer containing metal, silicon, nitrogen, and oxygen. The lower layer is thinner than the upper layer, and the ratio of metal to metal and silicon of the upper layer is less than the lower layer.

Provided is a mask blank wherein, even when a defect is present on the main surface of a substrate of the mask blank, the defect can be made to not affect a transfer image formed by a transfer mask, such that the mask blank is deemed acceptable. This mask blank is provided with a thin film that is for transfer pattern formation and provided on the main surface of a transparent substrate, wherein a defect is present on the main surface of the transparent substrate, and the defect satisfies the relationship L≤97.9×w.sup.−0.4, where w is the width as viewed from the main surface side, and L is the length from the main surface to the tip of the defect in a direction perpendicular to the main surface.

Provided is a mask blank wherein, even when a defect is present on the main surface of a substrate of the mask blank, the defect can be made to not affect a transfer image formed by a transfer mask, such that the mask blank is deemed acceptable. This mask blank is provided with a thin film that is for transfer pattern formation and provided on the main surface of a transparent substrate, wherein a defect is present on the main surface of the transparent substrate, and the defect satisfies the relationship L≤97.9×w.sup.−0.4, where w is the width as viewed from the main surface side, and L is the length from the main surface to the tip of the defect in a direction perpendicular to the main surface.

A mask for photolithography includes: a transparent substrate; a phase shift pattern on the transparent substrate and configured to change a phase of light; a dielectric layer on the transparent substrate; and a negative refractive-index meta material layer on the dielectric layer.

A mask for photolithography includes: a transparent substrate; a phase shift pattern on the transparent substrate and configured to change a phase of light; a dielectric layer on the transparent substrate; and a negative refractive-index meta material layer on the dielectric layer.

A halftone phase shift film containing Si and N and/or O is deposited on a transparent substrate by reactive sputtering of a Si-containing target with a reactive gas containing N and/or O. One layer is sputter deposited while the reactive gas flow rate is set equal to or lower than the lower limit of the reactive gas flow rate in the hysteresis region, and another layer is sputter deposited while the reactive gas flow rate is set inside the lower and upper limits of the reactive gas flow rate in the hysteresis region. The phase shift film exhibits satisfactory in-plane uniformity of optical properties.

A halftone phase shift film containing Si and N and/or O is deposited on a transparent substrate by reactive sputtering of a Si-containing target with a reactive gas containing N and/or O. One layer is sputter deposited while the reactive gas flow rate is set equal to or lower than the lower limit of the reactive gas flow rate in the hysteresis region, and another layer is sputter deposited while the reactive gas flow rate is set inside the lower and upper limits of the reactive gas flow rate in the hysteresis region. The phase shift film exhibits satisfactory in-plane uniformity of optical properties.