A method of fabricating a multi-tone amplitude photomask includes providing a mask substrate. The method includes providing a stepped pattern in at least one layer of material on a surface of the mask substrate. The stepped pattern includes at least two steps and at least three levels. Each level of the stepped pattern provides a different intensity of light when a light source shines light on the stepped pattern.

A method of fabricating a multi-tone amplitude photomask includes providing a mask substrate. The method includes providing a stepped pattern in at least one layer of material on a surface of the mask substrate. The stepped pattern includes at least two steps and at least three levels. Each level of the stepped pattern provides a different intensity of light when a light source shines light on the stepped pattern.

There is provided a mask blank including on a substrate: a thin film for forming a transfer pattern; a resist underlayer formed on the thin film and made of a resist underlayer composition containing a polymer having a unit structure having a lactone ring and a unit structure having a hydroxyl group; a resist film formed on the resist underlayer film and made of a resist composition; and a mixed film formed so as to be interposed between the resist underlayer film and the resist film and made of a mixed component containing the resist underlayer composition and the resist composition.

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.

A pattern is formed on a substrate with a layer of a curable composition (A1) containing a component (a1) serving as a polymerizable compound on a surface of the substrate, then dispensing droplets of a curable composition (A2) containing at least a component (a2) serving as a polymerizable compound and a component (b2) serving as a photopolymerization initiator dropwise discretely onto the curable composition (A1) layer to lay the droplets, subsequently sandwiching a mixture layer of the curable composition (A1) and the curable composition (A2) between a mold having a pattern and the substrate, then irradiating the mixture layer with light to cure the layer, and releasing the mold from the mixture layer after the curing, a Distance in Hansen space Ra((a1)−(A2)) between the component (a1) serving as a polymerizable compound in the curable composition (A1) and the curable composition (A2) being 6 or less.

A quartz etching method of the invention includes forming a mask on a quartz glass substrate and carrying out etching using a hydrofluoric acid-based etchant solution. The quartz etching method includes: preparing a quartz glass substrate; forming a mask having a predetermined pattern on the quartz glass substrate; and carrying out etching on the quartz glass substrate. When the quartz glass substrate is prepared, the quartz glass substrate is selected in accordance with a standard such that a concentration of hydroxyl groups included therein is less than or equal to 300 ppm.

A quartz etching method of the invention includes forming a mask on a quartz glass substrate and carrying out etching using a hydrofluoric acid-based etchant solution. The quartz etching method includes: preparing a quartz glass substrate; forming a mask having a predetermined pattern on the quartz glass substrate; and carrying out etching on the quartz glass substrate. When the quartz glass substrate is prepared, the quartz glass substrate is selected in accordance with a standard such that a concentration of hydroxyl groups included therein is less than or equal to 300 ppm.

According to an embodiment, a wafer (W) includes a layer (EL) to be etched, an organic film (OL), an antireflection film (AL), and a mask (MK1), and a method (MT) according to an embodiment includes a step of performing an etching process on the antireflection film (AL) by using the mask (MK1) with plasma generated in a processing container (12), in the processing container (12) of a plasma processing apparatus (10) in which the wafer (W) is accommodated, and the step includes steps ST3a to ST4 of conformally forming a protective film (SX) on the surface of the mask (MK1), and steps ST6a to ST7 of etching the antireflection film (AL) by removing the antireflection film (AL) for each atomic layer by using the mask (MK1) on which the protective film (SX) is formed.

According to an embodiment, a wafer (W) includes a layer (EL) to be etched, an organic film (OL), an antireflection film (AL), and a mask (MK1), and a method (MT) according to an embodiment includes a step of performing an etching process on the antireflection film (AL) by using the mask (MK1) with plasma generated in a processing container (12), in the processing container (12) of a plasma processing apparatus (10) in which the wafer (W) is accommodated, and the step includes steps ST3a to ST4 of conformally forming a protective film (SX) on the surface of the mask (MK1), and steps ST6a to ST7 of etching the antireflection film (AL) by removing the antireflection film (AL) for each atomic layer by using the mask (MK1) on which the protective film (SX) is formed.