KR100948770B1 - Blankmask, Photomask and it's Manufacturing Method - Google Patents

Abstract

In order to reduce the loading effect in which the size difference between the single mask and the dense pattern of the photomask occurs, at least a wet etching capable of etching and a light blocking film or a light shielding film and an antireflection film are laminated on a transparent substrate, and then at least the same etching as the etching blocking film or the light shielding film. After stacking the hard mask film having a characteristic and reducing the thickness of the photoresist, the photomask is exposed, developed, and the hard mask film is etched to use the photoresist pattern and / or the hard mask film as a mask. Provided are a blank mask and a photomask and a method of manufacturing the same, wherein the film is removed.

Blank mask, photo mask, hard mask, surface treatment, chemically amplified resist

Description

Blank mask, photomask and it's manufacturing method}

According to the present invention, a material of a photomask used for microfabrication such as an integrated circuit, a charge coupled device, a liquid crystal display, a color filter, etc. The present invention relates to a photomask blank and a method of manufacturing a photomask using the same.

In line with the fineness and demand of circuit patterns associated with the high integration of large scale integrated circuits, advanced semiconductor microprocessing technology is becoming a very important factor. In the case of high integrated circuits, circuit wiring has been miniaturized for low power and high speed operation, and technical requirements for contact hole patterns for interlayer connection and arrangement of circuit configurations due to integration are increasing. Therefore, in order to meet these requirements, even in the manufacture of a photomask in which a circuit pattern is recorded, which is used in lithography, it is possible to record a more precise circuit pattern with the above miniaturization. What skills are needed.

In general, a blank mask and a photomask are manufactured by laminating a light shielding film and an antireflection film on a transparent substrate or a substrate on which a phase inversion film is laminated on a transparent substrate, and then coating the photoresist and then exposing, developing, etching and stripping the photoresist. Patterns are formed through the conventional blank mask and the photomask, because the thickness of the photoresist is thick, even if exposed to the same size to the photoresist, the macro loading effect and the micro loading effect during etching. As a result, the size of the high integration pattern and the low integration pattern and the size of the single pattern and the dense pattern are different from each other. The above problem is that when the photoresist is etched after exposure and development, the film under the photoresist is etched using the photoresist as a mask, and the reaction rate and removal of reactants reacting per unit area with respect to the same developer, etching solution or etching gas amount. Since a pattern having a high density of patterns is smaller than a pattern having a low degree of integration or a single pattern, it is known that a difference in CD (critical dimension) occurs due to poor etching. That is, in the case of the dense pattern region, the concentration of etching radicals for etching the metal film is lowered toward the lower portion of the metal pattern than in the region where the pattern is to be formed, thereby increasing the top CD of the metal pattern. On the other hand, there is a difference between the bottom and the bottom CD. On the other hand, in the case of the isolated pattern region, since the region to be etched is small, the radical concentration is relatively high, resulting in undercut of the metal layer pattern. The CD difference will be large.

In order to solve the above problems, lowering the thickness of the photoresist improves the loading effect and the linearity and fidelity of the fine pattern. However, when the photomask is manufactured by dry etching, the etching rate of the photoresist and the etching material is not high, so When the photoresist is damaged and the shape of the resist pattern is changed and serious, the lower film is damaged, making it difficult to accurately transfer the original photoresist pattern onto the light shielding film. For this reason, it is necessary to reduce the burden on the photoresist used as a mask in pattern formation of a photomask.

In addition, the photoresist pattern is also miniaturized in response to the miniaturization of the formed photomask pattern. However, if only the resist pattern is miniaturized without reducing the thickness of the photoresist, the resist film thickness of the photoresist portion functioning as a hard mask for the light shielding layer and Aspect Ratio with pattern width becomes large. Generally, when the ratio of the photoresist thickness to the pattern width becomes large, the pattern shape tends to deteriorate, and the pattern transfer accuracy to the light shielding layer having this as a mask deteriorates. In extreme cases, a portion of the resist pattern may collapse or peel off, resulting in pattern omission. Therefore, with the miniaturization of the photomask pattern, it is necessary to make the film thickness of the resist used as the mask for light shielding layer patterning thin so that the ratio of pattern width to thickness does not become too large.

However, in reality, it is technically difficult to satisfy both the etching resistance, the high resolution, and the patterning precision of the photoresist mask, and it is difficult to fundamentally solve the above problems as long as the conventional patterning process is maintained.

As important as reducing the thickness of the photoresist, the thickness of the hard mask should be reduced. After patterning the hard mask layer with a resist mask, the hard mask is used as an etch mask by etching the resist to dry and wet etch the lower light shielding film and the anti-reflection film, which is hard in terms of macro and micro loading effects. The mask also needs to be thin. However, since the thickness optimization of the hard mask layer is also likely to be removed or damaged when etching the lower layer such as photoresist, consideration should be given to the material selection and thickness of the hard mask layer.

In order to solve these problems, it is necessary to reduce the load of the photoresist to form a more accurate photomask pattern, to optimize the selection of the light shielding film material, to optimize the etching resistance for the use of the photoresist, to heat treatment during the hard mask process, to select the thickness, It is necessary to propose new materials and structures of photomask blanks with good etching resistance through optimization of process conditions.

In addition, a chemically amplified resist was coated to increase the resolution in the blank mask and used in the fabrication of the photomask. The chemically amplified resist is a structure in which a strong acid (H +) is generated during exposure and a strong acid is amplified by a post exposure bake (PEB) process to develop a resist during development. However, in the conventional blank mask, the base on which the chemically amplified resist film is formed is a metal film. In the existing metal film, nitrogen has been added and used to control reflectance characteristics, etching characteristics, optical density, and the like. However, due to the nitrogen contained in the metal film, the strong acid generated in the chemically amplified resist is combined with nitrogen, which causes neutralization of the strong acid. The neutralization of the strong acid causes the phenomenon of the chemically amplified resist film to occur. The problem did not occur. If the chemically amplified resist film is not developed, a problem arises in realizing high resolution, and eventually a high quality photomask is difficult to produce.

The present invention has been made to solve the above problems, the drying effect is reduced during dry etching, linearity (linearity), the etching selectivity (etchivity) is improved, the vertical pattern of the metal film is possible, chemically amplified resist pattern An object of the present invention is to provide a blank mask and a photomask which are well formed and a method of manufacturing the same.

In order to achieve the above object, the present invention is characterized in that a blank mask, which is a raw material of a photomask, laminates a metal film on a transparent substrate and a hard mask film is stacked thereon.

In the blank mask manufacturing method according to the present invention,

a1) preparing a substrate;

b1) selectively forming an etch stop layer on the substrate prepared in step a1);

c1) forming a metal film on the substrate prepared in step a1) or the transparent substrate prepared in on the etch stop film formed in step b1);

d1) forming a hard mask film on the metal film formed in step c1);

e1) performing a surface treatment using an organic material containing silicon selectively on the hard mask film formed in step d1);

f1) forming a resist mask on the hard mask film subjected to the surface treatment in step e1) to manufacture a blank mask.

In step a1), the substrate refers to a transparent substrate having a size of 6025, which is generally used, and the material may be a material such as synthetic quartz substrate and soda lime glass.

In step a1), when the substrate is required to be applicable to Immersion Lithography, the birefringence is characterized in that less than 5nm / 6.35mm.

In step b1), the etch stop layer is selectively formed as necessary.

In step b1), the etch stop layer is preferably formed to a thickness of 3 to 30nm. If the etch stop layer is less than 3nm, it will not function as an etch stop, which may cause loss of the transparent substrate, and loses the function of the light shielding film that blocks light. If the thickness is more than 30 nm, the undercut of the etch stop layer is increased, thereby affecting the CD, or the process time is increased due to the long etching time, thereby decreasing productivity.

In the step b1), the etch stop film is a metal as a main component and used as the metal alone, or one type selected from oxides, carbides, nitrides, oxidized carbides, oxynitrides, carbonitrides, oxynitrides of the metal It is done.

In the step b1), the etch stop film is not dry etching the fluorine-based gas, it is characterized in that the chlorine-based gas is etched. In this case, the chlorine-based gas for etching the etch stop layer may be dry etched only, and the metal layer formed directly on the substrate or the etch stop layer may not be etched. In addition, it is possible to etch the hard mask film formed on the metal film.

In step b1), the etch stop layer includes Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, It is characterized in that it comprises one or two or more metals selected from Sn, Hf, Ta, W, Os, Ir, Pt, Au.

In the step b1), the etch stop layer is characterized in that at least one type selected from Cr, CrN, CrC, CrO, CrCN, CrON, CrCO, CrCON, in particular, Cr as the main component, preferably Cr, CrC , CrCN, characterized in that at least one type selected from CrN.

In the step b1), the etch stop layer is characterized in that at least one type selected from Ta, TaC, TaN, TaO, TaCN, TaON, TaCO, TaCON, in particular when Ta as the main component, preferably Ta, TaC , TaCN, TaN is characterized in that at least one type selected from.

In the step b1), it is also possible that the etch stop layer includes Ta and Cr as main components at the same time. For example, TaCr, TaCrC, TaCrN, TaCrO, TaCrCN, TaCrCO, TaCrON, TaCrCON and the like are also possible.

In the step b1), in the case where the etch stop layer is a compound mainly composed of Cr to / and Ta, Cr to / and Ta is 30 to 90 at%, preferably 50 to 80 at%, carbon is 0 to 30 at%, Preferably 5 to 25 at%, oxygen is 0 to 10 at%, preferably 0 to 5 at%, nitrogen is 0 to 60 at%, preferably 10 to 50 at%. In this case, when Cr to Ta is less than 30at%, the etch stop layer loses the function of the etch stop layer substantially due to the addition of Cr to Ta. In addition, in the case of carbon exceeding 30at% carbon is added excessively to the etch stop layer, the etching rate is reduced, the particle generation is increased, the reliability of the chemical is reduced. When oxygen exceeds 10at%, the reliability of the chemicals of the etch stop film is lowered, and the transmittance of the etch stop film becomes high, which adversely affects the optical density characteristics, resulting in a problem that the thickness of the etch stop film needs to be made thick. Done. And in case of nitrogen exceeds 60at%, the reliability of the chemical is lowered, and the etching rate during the etching process becomes faster, it is difficult to control the etching time.

In the step c1), the metal film is characterized in that a single film or a multilayer film structure of two or more layers.

In the step c1), if the metal film is a single film, it includes a function of the light shielding film that can block light with only a single film and a function of an anti-reflection film to reduce the reflection of light.

In the step c1), if the metal film is a multi-layered film of two or more layers, it is characterized by being divided into a function of a light shielding film capable of shielding light and an antireflection film which reduces reflection of light.

In the step c1), the metal film is essentially composed of Si, and in addition to Si, it is characterized in that the composition consists of only one or two or more metals.

In the step c1), the metal film is made of metal + Si, characterized in that one of the forms selected from the oxide, nitride, carbide, oxynitride, oxidized carbide, carbide oxide.

In the step c1), when the metal film essentially contains metal + Si, the metal is Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, It is characterized by containing one or two or more selected from Rh, Pd, Ag, Cd, In, Sn, Hf, Ta, W, Os, Ir, Pt, Au.

In the step c1), when the metal film is composed of a single film, the metal film is characterized in that one type selected from MoSi, MoSiC, MoSiN, MoSiO, MoSiON, MoSiCN, MoSiCO, MoSiCON.

In the step c1), when the metal film is composed of a single film, the metal film is characterized in that one type selected from MoTaSi, MoTaSiC, MoTaSiN, MoTaSiO, MoTaSiON, MoTaSiCN, MoTaSiCO, and MoTaSiCON.

In the step c1), when the metal film is composed of a two-layer film, the lower layer film from the substrate functions as a light shielding film, and an anti-reflection film is formed on the light shielding film. In this case, when the light shielding film and the antireflection film mainly contain MoSi, the light shielding film is composed of MoSi, MoSiC, MoSiN, MoSiCN, and the antireflection film is MoSiN, MoSiO, MoSiON, MoSiCN, MoSiCO, MoSiCON. do. In addition, when the light shielding film and the antireflection film mainly contain MoTaSi, the light shielding film is composed of MoTaSi, MoTaSiN, MoTaSiC, and MoTaSiCN. do. In this case, the light shielding film may include MoSi as a main component, and the antireflection film may be mixed with MoTaSi as a main component, and the light shielding film may include MoTaSi as a main component and the antireflection film may include MoSi as a main component.

In the step c1), when the metal film is composed of a two-layer film, and the light shielding film is composed of only MoSi, Mo is 20 to 70 at%, preferably 30 to 60 at%, Si is 30 to 70 at%, preferably 40 to 60 at It is characterized by being%.

In the step c1), when the metal film is composed of a two-layer film, and the light shielding film is composed of a MoSi compound, Mo is 1 to 20 at%, preferably 3 to 15 at%, Si is 40 to 80 at%, preferably 50 to 70 at%, nitrogen is 10 to 50 at%, preferably 20 to 40 at%, carbon is 0 to 10 at%, preferably 0 to 5 at%.

In the step c1), when the metal film is composed of a two-layer film, and the anti-reflection film is composed of a MoSi compound, Mo is 1 to 20 at%, preferably 3 to 15 at%, and Si is 40 to 80 at%, preferably 50 70 at%, oxygen is 0-10 at%, preferably 0-5 at%, nitrogen is 10-50 at%, preferably 20-40 at%, carbon 0-10 at%, preferably 0-5 at% It features.

In the step c1), when the metal film is composed of a two-layer film, and the light shielding film is composed of only MoTaSi, Mo is 10 to 60 at%, preferably 20 to 50 at%, Ta is 2 to 30 at%, preferably 5 to 20 at% and Si are 30 to 70 at%, preferably 40 to 60 at%.

In the step c1), when the metal film is composed of a two-layer film and the light shielding film is composed of a MoTaSi compound, Mo is 1 to 15 at%, preferably 3 to 12 at%, and Ta is 1 to 15 at%, preferably 3 to 12 at%, Si is 40 to 80 at%, preferably 50 to 70 at%, nitrogen is 10 to 50 at%, preferably 20 to 40 at%, carbon is 0 to 10 at%, preferably 0 to 5 at% It is done.

In the step c1), when the metal film is composed of a two-layer film and the anti-reflection film is composed of a MoTaSi compound, Mo is 1 to 15 at%, preferably 3 to 12 at%, and Ta is 1 to 15 at%, preferably 3 12 at%, Si 40 to 80 at%, preferably 50 to 70 at%, oxygen 0 to 10 at%, preferably 0 to 5 at%, nitrogen at 10 to 50 at%, preferably 20 to 40 at%, carbon Is 0 to 10at%, preferably 0 to 5at%.

In the step c1), the metal film may be dry etched by the fluorine-based gas and not etched by the chlorine-based gas. At this time, the fluorine-based gas is characterized in that the etching stop film, the hard mask film is not etched.

In the step c1), the reflectance of the metal film is characterized in that less than 25% at an exposure wavelength of 193nm.

When the metal film is formed on the substrate through the steps a1) and c1), the optical density at 193 nm is 2.5 or more.

When the etch stop layer and the metal layer are sequentially formed on the substrate through the steps a1) to c1), the optical density at 193 nm is 2.5 or more.

When the metal film is formed on the substrate through the steps a1) and c1), the thickness of the metal film is 500 Å or less.

When the etch stop layer and the metal layer are sequentially formed on the substrate through the steps a1) to c1), the thickness of the etch stop layer and the metal layer is 500 Å or less.

In the step d1), the hard mask film is a metal as a main component and is used alone or in one form selected from oxides, carbides, nitrides, oxidized carbides, oxynitrides, carbonitrides and oxynitrides. It is done.

In the step d1), the metal of the hard mask film is Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, It is characterized by containing one or two or more selected from In, Sn, Hf, Ta, W, Os, Ir, Pt, Au.

In step b1), it is also possible that the hard mask film contains Ta and Cr as main components at the same time. For example, TaCr, TaCrN, TaCrO, TaCrC, TaCrCN, TaCrCO, TaCrON, TaCrCON and the like are also possible.

In the step d1), the hard mask film has Cr and / or Ta as a main component thereof, and is one or more of these selected from the forms of nitriding, carbonization, oxidation, nitriding carbonization, nitriding oxidation, carbonization oxidation, and nitriding carbide oxide. It is characterized by.

In the step d1), the composition of the hard mask film is 30 to 70 at% of transition metal, preferably 40 to 60 at%, 0 to 30 at% of carbon, preferably 0 to 20 at%, 0 to 20 at% of oxygen, Preferably 0 to 15 at%, nitrogen is characterized by having a composition ratio of 0 to 40 at%, preferably 0 to 30 at%.

In the step d1), the hard mask film is not dry etched in the fluorine-based gas, it is characterized in that the chlorine-based gas is etched. In this case, the chlorine-based gas for etching the hard mask film may be dry etched only with the hard mask, and the metal film formed directly below the hard mask film may not be etched. In addition, the etching stop layer formed on the substrate is characterized in that the etching by the etching gas capable of etching the hard mask.

In step d1), the hard mask film is preferably formed to a thickness of 3 to 30nm. When the hard mask layer is less than 3nm, the hard mask layer may not serve as a hard mask layer, and the metal layer may be lost during dry etching. In addition, when the etching time is longer than 30 nm, the process time is increased due to the longer etching time, and the loading effect occurs during dry etching due to the thick thickness, which makes it difficult to implement high quality CD.

When the etch stop layer, the metal layer, and the hard mask layer are sequentially formed on the substrate through the steps a1) to d1), the thickness of the etch stop layer is thicker than that of the hard mask layer. This is because when the thickness of the etch stop layer is thinner than the thickness of the hard mask layer, undercut of the etch stop layer occurs during dry etching, which makes it difficult to implement high quality CD.

When the etch stop layer, the metal layer, and the hard mask layer are sequentially formed on the substrate through the steps a1) to d1), the etch rate of the etch stop layer is faster than that of the hard mask layer. This is because when the etching speed of the etch stop film is slower than that of the hard mask film, undercut of the etch stop film occurs during dry etching, which makes it difficult to implement high quality CD.

In the step e1), the surface treatment is mainly carried out by heat treatment, the heat treatment method for the surface treatment is a hot plate (Hot-plate), vacuum hot plate (Vacuum Hot-plate), vacuum oven (Vacuum) Oven), a vacuum chamber (Vacuum Chamber), it characterized in that it is made through a method selected from the furnace (Furnace).

In the step e1), the surface treatment is mainly carried out by heat treatment, if the heat treatment for the surface treatment is carried out through a lamp, Rapid Thermal Process (RTP), heat ray, UV lamp (Lamp) Halogen lamps and the like are optionally applied.

In the step e1), the temperature used during the heat treatment is 100 ~ 1000 ℃ is applied, preferably 200 ~ 800 ℃ is applied.

In the step e1), the vacuum degree used in the surface treatment is 0 ~ 0.5 Pa is applied, preferably 0.1 ~ 0.3 Pa is applied.

In the step e1), the time used for the surface treatment is applied 1 to 60 minutes, preferably 5 to 40 minutes.

In the step e1), N ₂ , Ar, He, Ne, Xe and the like are used as the atmosphere gas used in the surface treatment.

In the step e1), including the step of cooling after the surface treatment process, the cooling is applied at atmospheric pressure or vacuum.

In the step e1), the medium used for the surface treatment is a liquid or gaseous state.

In the step e1), the medium used in the surface treatment is a medium containing essentially silicon.

In the step e1), the medium essentially containing silicon is hexamethyldisilane (Hexamethyldisilane), trimethylsilyl diethylamine, O-trimethylsilyl acetate (O-trimethylsilyl-acetate), O-trimethylsilyl Propionate (O-trimethylsilylproprionate), O-trimethylsilylbutyrate, Trimethylsilyltrifluoroacetate, Trimethylmethoxysilane, N-methyl-N-trimethylsilyltrifluoro Acetamide (N-methyl-N-trimethyl-silyltrifluoroacetamide), O-trimethylsilylacetylacetone, Isopropenoxytrimethylsilane, Trimethylsilyltrifluoroacetamide, Methyltrimethylsilyl Methyltrimethylsilyldimethylketone acetate, in trimethyl Sisilran (Trimethylethoxysilane) is one kind or not less than two kinds selected from a.

In the step f1), the resist film is formed through a positive or negative chemically amplified resist.

In the step f1), the resist film is formed by a method selected from among spin coating, scan coating, scan + spin, and spray coating.

In the step f1), the thickness of the resist film is 200 to 4000 mm.

In the step f1), after the resist film is formed, the soft bake is baked on a hot plate under a condition of 5 to 30 minutes at a temperature of 90 to 170 ° C.

In the step f1), after the resist film is formed, soft baking is performed, and cooling is performed under a condition of 5 to 30 minutes in a cool plate having a constant 23 degrees.

When nitrogen is essentially included in the hard mask film in step d1), the surface treatment of step d1) is essentially performed. The strong acid generated from the chemically amplified resist film is combined with the nitrogen contained in the metal film to neutralize the strong acid. The neutralization reaction of strong acid occurs due to Lewis bond, because nitrogen acts as Lewis Base and strong acid as Lewis Acid. As a result, a strong acid of the chemically amplified resist is neutralized at the interface between the chemically amplified resist and the hard mask film, so that the cum which does not develop the chemically amplified resist is developed. This phenomenon is referred to as substrate dependency. This substrate dependency makes it difficult to implement the desired target CD, which makes it difficult to manufacture high quality photomasks. Therefore, surface treatment must be carried out when nitrogen is essentially included in the hard mask.

In the case of d1), when nitrogen is not included in the hard mask layer, the surface treatment of d1) may be selectively performed. When nitrogen is not included in the hard mask film, the substrate dependency of the chemically amplified resist due to the neutralization of the strong acid does not occur, but surface treatment is preferably performed to increase the adhesion of the resist or to relieve stress of the thin film.

In steps b1) to e1), reactive sputtering or vacuum deposition methods (PVD, CVD, etc.) formed by introducing an inert gas and a reactive gas in a vacuum chamber when forming an etch stop layer, a metal layer, or a hard mask layer. ALD). In this case, as the reactive gas, methane (CH ₄ ), acetylene (C ₂ H ₂ ), ethylene (C ₂ H ₄ ), propane (C ₃ H ₈ ), vinylacetylene (C ₄ H ₄ ), divinylacetylene ( C ₆ H ₆ ), butane (C ₄ H ₁₀ ), butylene (C ₄ H ₈ ), ethane (C ₂ H ₆ ), nitrogen (N ₂ ), oxygen (O ₂ ), carbon monoxide (CO), carbon dioxide ( At least one selected from the group consisting of CO ₂ ), fluorocarbon (CF ₄ ), nitrous oxide (N ₂ O), nitrogen oxides (NO), nitrogen dioxide (NO ₂ ), ammonia (NH ₃ ) and fluorine (F). Can be selected and used. More preferably, carbon is included to lower the reflectance. The vacuum chamber has a degree of vacuum of 0.1 to 30 mTorr and an applied power of 0.1 to 3 kW, and the mixing ratio of the reactive gas is 10 to inert gas: nitrogen (N ₂ ): oxygen (O ₂ ): methane (CH ₄ ). 100%: 0 to 95%: 0 to 95%: 0 to 95%. At least one of nitrous oxide (N ₂ O), nitrogen oxides (NO), nitrogen dioxide (NO ₂ ), ammonia (NH ₃ ), and fluorine (F) may be used instead of nitrogen or oxygen or nitrogen and oxygen.

In the above steps b1) to e1), when forming the etch stop layer, the metal layer, or the hard mask layer, the carbon element preferably has a composition ratio of 0 to 10 at%. This is because as the carbon content in the film composition ratio increases, the sheet resistance of the thin film is lowered. When it exceeds 10%, the sheet resistance property is deteriorated, and the reliability property of the thin film is degraded.

In the above steps b1) to e1), the sheet resistance values of the etch stop layer, the metal layer, and the hard mask layer may be 1,000 Ω or less. When the sheet resistance is high during electron beam exposure for photomask fabrication, a charge up phenomenon may occur. When the charge-up phenomenon occurs, pattern defects may occur or the position of the pattern may be shifted to cause pattern position defects. It is more preferable that the sheet resistance value be 1,000 Ω or less by adjusting the composition ratio of carbon in the film as described above.

In steps b1) to e1), the SPM process using sulfuric acid or ammonia for the etch stop layer, the metal layer, and the hard mask layer, and the reflectance at 193 nm should be within 1% when dipping for 2 hours for SC1. . Generally, in the process of manufacturing a photomask using a blank mask, the cleaning process is performed three to ten times. Therefore, if the laminated film does not have high chemical resistance to the cleaning liquid, the CD may be changed by the change of the transmittance and the reflectance.

In the steps b1) to e1), in the etch stop layer, the metal layer, and the hard mask layer, each thin film has a density of 2 g / cm 3 or more. At this time, if the density of the thin film is less than 2g / cm 3, the function of blocking the exposure light in the etch stop film, the light shielding film, and the anti-reflective film is reduced, so that the thin film is not required to act as a practical light blocking film. The effect of improvement is diminished. In addition, when chemicals such as sulfuric acid or ammonia, which are used to clean the blank mask and photomask, come into contact with a thin film with low density, chemical reactions occur easily on the surface of the thin film, resulting in poor chemical resistance and change in characteristics of the thin film. As a result, problems such as reflectance change are caused, and thickness change occurs, thereby making it difficult to control optical density. It also creates an environment where haze defects, which are growth defects, can easily occur. When the density of the thin film is low, the surface energy increases, and chemicals such as sulfuric acid and ammonia are easily formed on the surface to form chemical and physical bonds and remain on the surface, and these residual chemicals remain in lithography process in the semiconductor manufacturing process. Reaction is caused by exposure light to form haze defects. Therefore, the density of the thin film is required to be 2 g / cm 3 or more. The density of the thin film can be adjusted by adjusting the composition ratio of the thin film. The composition ratio of the thin film is determined by the composition ratio of the sputtering target, the type and the flow rate of the reactive gas used in the sputtering process. In addition to the composition ratio of the thin film, the sputtering process conditions, such as pressure, power, substrate heating (heating) and the like can be controlled by the process conditions. In addition, the sputtering target used in forming the thin film is suitable to use a target manufactured by HIP (hot iso-static pressing) method.

In the steps b1) to e1), the etch stop layer, the metal layer, and the hard mask layer are in an amorphous state. The amorphous state of the thin film is possible through the substrate heating temperature control during the sputtering process, suitably 700 ° C. or less, and more preferably 500 ° C. or less. If the thin film has crystallinity, the edge roughness of the pattern becomes poor when the pattern is formed, which adversely affects the CD characteristics, making it difficult to manufacture a high quality photomask.

In the steps b1) to e1), it is preferable to selectively heat treatment at a temperature of 100 ° C to 500 ° C after the preparation of the etch stop layer, the metal layer, and the hard mask layer. This heat treatment process may be selectively performed separately from the surface treatment performed in step e1). Through heat treatment, the etching resistance and chemical resistance of the lower light blocking film and the anti-reflection film may be improved by etching the lower light blocking film and the antireflection film without changing the reflectance, dry and wet etch rate. The step of the heat treatment is not limited to the blank mask manufacturing, and even if the heat treatment is performed after the hard mask patterning with the resist etching mask during the photomask manufacturing, there is no difference in effect according to the heat treatment. By performing the heat treatment as described above to improve the etching resistance of the hard mask film it is possible to configure a hard mask film having a lower thickness. As a hard mask layer having improved etching resistance, the lower metal layer may be etched and the thickness thereof is low, thereby increasing the surface area response to the etching gas and the etching liquid during etching. Therefore, since the etching resistance is high and the hard mask thickness can be reduced, the etching selectivity for the etching of the lower layer can be improved, and the CD characteristics such as the linearity and fidelity of the CD can be improved, and the exposure dose for photomask manufacturing There is a reduction effect.

As described above, the blank mask and the photomask of the present invention provide the following effects.

First, by removing the substrate dependence of the chemically amplified resist film, high-precision pattern precision and pattern transfer precision of the photoresist are enabled, thereby providing a blank mask that can make CD very excellent.

Second, by performing heat treatment when forming the hard mask film, the etching resistance of the hard mask film is improved in the range of no change in reflectance and etching rate, thereby reducing damage to the surface of the lower anti-reflection film and the light shielding film during dry and wet etching. It provides a blank mask capable of pattern transfer, low thickness, high etching selectivity, and very good CD.

Third, the invention provides a photomask having a very good quality of Fidelity, linearity, Iso-Dense Bias, LER in the pattern of 50 ~ 100nm using the blank mask invented.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. The embodiments described below may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below.

(Example 1)

In this embodiment, two kinds of blank masks are used by varying the thickness of the photoresist in order to see the difference of linearity, dense pattern-single pattern, pattern formation (LER: Line Edge Roughness), and fidelity according to the thickness of the photoresist. Produced.

1A to 1F illustrate a method of manufacturing a blank mask and a photomask according to a first embodiment of the present invention.

As shown in FIG. 1A, in the blank mask according to the present embodiment, an etch stop film 2, a light shielding film 3, an antireflection film 4, and a hard mask film 5 are sequentially formed on a substrate 1. It was. Next, a blank mask fabricated by coating the chemically amplified resist 6 is illustrated in FIG. 1B.

More specifically, first, the chromium carbonitride (CrCN) etch stop film is applied to the chromium nitride (CrCN) etch barrier film by applying DC power by a reactive sputtering method under a gas condition of chromium target and argon: nitrogen: methane = 40sccm: 15sccm: 5sccm on a transparent substrate. Laminated to thickness. In the case of the chromium carbonitride (CrCN), wet etching is possible by CR7-S used as a chromium etching solution, and also dry etching is possible by chlorine (Cl ₂ ) gas and oxygen (O ₂ ) gas. At this time, the heating temperature of the substrate was maintained until the temperature of 470 ℃ hard mask film formation. In addition, the sputtering process pressure is 1 ~ 5mtorr applied to the etch stop film, light shielding film, anti-reflective film, and hard mask film, and 100 ~ 2000W power is applied to the etch stop film, light shielding film, anti-reflection film, and hard mask film for sputtering power. Applied ..

Then, a MoTaSi light shielding film was laminated on the etch stop layer using a target having a composition ratio of 15: 5: 80at% of molybdenum: tantalum: silicon and an inert gas argon (Ar) 80sccm at a thickness of 30 nm. It was. Subsequently, MoTaSiN was laminated to a thickness of 10 nm by applying DC power under the gas condition of argon (Ar): nitrogen (N ₂ ) = 60sccm: 15sccm to the same target in manufacturing the light shielding film.

MoTaSi-based materials have been applied to metal films such as the light shielding film and the anti-reflection film, but a metal film of MoSi base can be formed. MoTaSi is more suitable as a metal film material because the extinction coefficient (k) of MoTaSi is higher than that of MoSi, so that an appropriate optical density can be realized at an earlier thickness. In addition to MoTaSi, other transition metals with higher extinction coefficients may be applied.

After stacking the etch stop layer, the light shielding layer, and the anti-reflective layer, the optical density was measured at 2.98 including the etch stop layer at 193nm, which is an ArF exposure wavelength, and the reflectance at the surface of the anti-reflective layer at 193nm was measured at 18.2%. There was no.

On top of that, the chromium carbide oxynitride (CrCON) hard mask film was applied by applying DC power by a reactive sputtering method under a chromium (Cr) target and argon: oxygen: nitrogen: methane = 40sccm: 5sccm: 10sccm: 3sccm. Laminated to.

The sheet resistance was measured to determine whether there is a charge up problem when the E-beam is exposed on the surface of the hard mask layer. The sheet resistance was 200 Ω / □, which was no problem.

At this time, the CrCN etch stop layer, the MoTaSi light shielding film, the MoTaSiN anti-reflection film, and CrCON were formed on the transparent substrate, and the density of the thin film was measured through X-ray reflectivity (XRR). It was measured as 2.7 g / cm 3 for the etch stop film, 3.25 g / cm 3 for the light shielding film, 2.95 g / cm 3 for the antireflection film, and 2.36 g / cm 3 for the hard mask film. A minimum density of 2 g / cm 3 of thin film is required. When the density of the thin film is less than 2g / cm 3, the function of blocking the exposure light in the etch stop film, the light shielding film, and the anti-reflection film is deteriorated, so that the thin film is not required to act as a practical light blocking film, thereby improving the loading effect. The effect is to fall. In addition, when chemicals such as sulfuric acid or ammonia, which are used to clean the blank mask and photomask, come into contact with a thin film with low density, chemical reactions occur easily on the surface of the thin film, resulting in poor chemical resistance and change in characteristics of the thin film. As a result, problems such as reflectance change are caused, and thickness change occurs, thereby making it difficult to control optical density. It also creates an environment where haze defects, which are growth defects, can easily occur. When the density of the thin film is low, the surface energy increases, and chemicals such as sulfuric acid and ammonia are easily formed on the surface to form chemical and physical bonds and remain on the surface, and these residual chemicals remain in lithography process in the semiconductor manufacturing process. Reaction is caused by exposure light to form haze defects. Therefore, the density of the thin film is required to be 2g / cm 3 or more. The density of the thin film can be adjusted by adjusting the composition ratio of the thin film. In addition, the sputtering target used in forming the thin film is suitable to use a target manufactured by HIP (hot iso-static pressing) method.

In order to determine the crystallization state of the thin film, each thin film, ie, an etch stop film, a light shielding film, and an antireflection film, was formed on each substrate in the same manner as described above. The measurement was carried out. All of the measurement results were measured in an amorphous state. Therefore, it can be seen that a pattern having excellent line edge roughness (LER) characteristics is formed after pattern formation.

Next, after forming a hard mask film, the surface treatment was performed using a hot-plate. At this time, the surface treatment was performed by HMDS Vapor Priming method and was carried out at 150 ℃ / 10 minutes. This is to obtain high quality CD by forming excellent pattern profile through scum prevention by Substrate dependency when forming pattern using chemically amplified resist.

Next, the FEP-171, a positive chemically amplified photoresist (CAR) for an electron beam exposure apparatus, was spin-coated to a thickness of 200 nm and 300 nm, respectively, followed by soft baking to form a blank mask. Prepared.

In order to see the CD difference according to the difference in the thickness of the photoresist, 200 nm photoresist was applied as compared with the conventional 200 nm thick resist. The thickness of the photoresist is lower than that of CD, that is, the aspect ratio (resist thickness / CD size) is small, so that the thickness of the photoresist is 200 nm for accurate photomask fabrication of the CD. In order not to change the viscosity of the photoresist, the amount of photoresist applied, the number of revolutions of each coating step, the drying method, the soft bake temperature, and the like, the coating method was similarly applied using a controlled method.

Next, a method of manufacturing the photomask according to the present embodiment using the blank mask manufactured as described above will be described with reference to FIGS. 1C to 1G.

First, referring to FIG. 1C, the blank mask was exposed using an electron beam exposure apparatus. The electron beam exposure apparatus exposed a pattern having a CD of 50 nm to 100 nm using an acceleration voltage of 50 kV.

Then, a resist pattern was formed by performing a post exposure bake (PEB) and a developing process.

Next, referring to FIG. 1D, hard etching of chromium carbonitride (CrCON) by dry etching (chlorine (Cl ₂ ): oxygen (O ₂ ) = 80sccm: 5sccm, 40W, 1Pa) using the patterned photoresist as an etching mask. The mask film was patterned.

Next, referring to FIG. 1E, after the hard mask film is patterned using the resist pattern as a mask, the remaining photoresist is removed by an ashing method using oxygen (O 2) gas.

Next, referring to FIG. 1F, the light-masking film and the anti-reflection film were removed by dry etching (CF ₄ = 80 sccm, 40W, 1Pa) using the pattern of the hard mask film as an etching mask.

Next, referring to FIG. 1G, after removing the light blocking film and the anti-reflection film, the lowermost etch stop layer was removed using CR-7S, which is used as a chromium etching solution, and at the same time, the chromium carbide oxynitride used as the etching mask of the light blocking film and the anti-reflection film ( The hard mask of CrCON) was also removed at the same time. In this case, the etching of the lowermost layer of the etch stop layer may be etched through wet etching through chlorine gas and oxygen gas as well as wet etching. In the dry etching process, the etching stop layer and the hard mask layer are simultaneously etched.

Then, cleaning was performed to complete the photomask 200 according to the first embodiment of the present invention. As a result of observing the cross section by scanning electron microscope based on two kinds of photomasks, the etching cross-sectional shape (LER) was good, and no step was found between the light shielding film and the anti-reflection film, and the light shielding film and the reflection were fluorine-based dry etching. It was confirmed that the protective film can be patterned by one operation. CD differences between fidelity, dense pattern and single pattern are shown in FIG. 2. Fidelity was defined as the specific ratio of the contact hole pattern (measured CD area / designed CD area). Dense and single patterns were evaluated with the difference between the designed CD and the patterned CD. As a result of the evaluation, the lower the thickness of the resist, the higher the fidelity, and the smaller the CD difference between the dense pattern and the single pattern. As a result, it was confirmed that excellent CD formation was possible by applying a low thickness of the photoresist in order to solve the problem of increasing the Aspect Ratio as the CD was reduced. As a result, the pattern was increased by the reactive gas during dry etching, so the aspect ratio of the lower resist was smaller than that of the high resist, so the actual CD difference was reduced.

From the above results, there is an advantage that the difference in the CD size and fidelity of the single pattern and the dense pattern can be further improved by making the required film thickness of the resist thin when producing the photomask with the blank of the present invention. In addition, in the present embodiment, the blank mask is composed of a transparent substrate, an etch stop film, a light shielding film, an antireflection film, a hard mask film, and a resist film. However, the present invention can be applied to a halftone phase inversion blank mask as it is. That is, the present invention can be applied to a halftone phase inversion blank mask composed of a transparent substrate, a phase inversion film, an etch stop film, a light shielding film, an antireflection film, a hard mask film, and a resist film. At this time, the phase inversion film means a phase inversion film composed of MoSiN, MoSiO, MoSiC, MoSiON, MoSiCN, MoSiCO, MoSiCON, etc. composed of a single film or a multilayer film, or MoTaSiN, MoTaSiO, MoTaSiON, MoTaSiCN, MoTaSiCO, MoTaSiCON. In the case of the phase inversion film composed of only two or more layers, the lower layer mainly controls the transmittance from the substrate and the transmittance control film of TaHf, Ta, Hf, etc., which controls the phase, and the upper layer mainly controls the phase inversion and also the transmittance. Mean phase inversion control film such as SiO, SiN, SiON, MoSiO, MoSiN, MoSiCN, MoSiCO, MoSiCON, MoTaSiO, MoTaSiN, MoTaSiCN, MoTaSiCO, MoTaSiCON. In addition, the etch stop layer may be omitted in the halftone phase inversion blank mask structure.

(Example 2)

Unlike the first embodiment, the thickness of the hard mask is different in order to see the difference of linearity, dense pattern, single pattern, etch cross section (LER: line edge roughness), and fidelity according to the thickness of the hard mask. Differently, two kinds of blank masks were produced. In order to see only the difference in the thickness of the hard mask film, a film was formed with the same structure and the same chemically amplified resist was applied.

First, a 15 nm etch stop film is laminated on a transparent substrate in the same manner as in the first embodiment, and a 35 nm thick light-shielding film of molybdenum silicide (MoSi) and a 15 nm molybdenum silicide nitride (MoSiN) are deposited thereon. An antireflection film was laminated. Then, in order to confirm the difference in the amount of CD change according to the thickness of the hard mask layer, 15 nm and 30 nm hard mask film was manufactured and then heat treated at 300 ° C. for 1 hour.

Next, a blank mask was prepared by coating FEP-171, a positive chemically amplified photoresist (CAR), to a thickness of 150 nm.

After exposure, PEB, and development using the blank mask, dry etching was performed to remove the hard mask film, the antireflection film, and the light shielding film, and the lowermost etch stop film was removed by wet etching with CR-7S. The results are shown in FIG.

As compared with the results of the first embodiment, it can be seen that the smaller the CD ratio is, the smaller the Aspect Ratio of the photoresist with respect to the hard mask. Judging from the same principle, the experimental results show that by reducing the thickness of the hard mask film, the aspect ratio is reduced when etching the lower anti-reflection film and the light shielding film, thereby improving the reactivity to dry etching gas, thereby significantly reducing the CD difference amount. .

(Example 3)

This embodiment is an evaluation example of the etching resistance characteristics according to whether or not heat treatment is performed after the deposition of the hard mask film in the blank mask process. After the hard mask film lamination, the blank mask, which was heat treated at 350 ° C. for 40 minutes, and the blank mask not subjected to heat treatment were prepared and evaluated.

In order to see only the difference in the heat treatment effect on the hard mask film, a film was formed in the same structure as in the first embodiment, and the same chemically amplified resist having a thickness of 200 nm was applied.

The hard mask layer was then removed by dry etching using the resist pattern as an etching mask after electron beam exposure, PEB and development. The photoresist film remaining after removing the hard mask film was removed by ashing. The anti-reflection film and the light shielding film were removed using the hard mask film pattern as an etching mask, and the etch stop film and the hard mask film were removed by wet etching.

As a result of observing with a scanning electron microscope to see the results of the dry etching of the light blocking film and the antireflection film with a hard mask pattern, the pattern mask of the blank mask without heat treatment was severely deteriorated, and the etched cross-sectional shape of the heat treated blank mask was observed. Was good. As a result, the hard mask film not subjected to the heat treatment was not etched because it did not meet the etching resistance during the dry etching of the light shielding film and the antireflection film, and thus, the hard mask film was etched to damage the antireflection film and the light shielding film.

From the above results, it can be seen that by performing heat treatment during the manufacture of the hard mask film of the present invention, the etching resistance can be improved to form a pattern with a low hard mask film, thereby enabling a more precise CD implementation while reducing the aspect ratio.

(Example 4)

This embodiment is an embodiment according to the surface treatment in the blank mask process. In the blank mask fabrication, a metal film composed of a light shielding film and an antireflection film was formed on a transparent substrate as in Example 1, and a hard mask film containing essentially nitrogen was formed. Next, the same surface treatment as in Example 1 was performed on the hard mask film, followed by spin coating the chemically amplified resist to a thickness of 200 nm to prepare a blank mask. And the blank mask which did not surface-treat for the comparison was simultaneously performed.

Next, the blank mask manufactured through the above process was exposed to the resist film through electron beam exposure having an acceleration voltage of 50 kV. Then, the PEB and the development process were performed to observe the pattern profile of the resist film.

As a result of the observation, referring to FIG. 4A, when the surface treatment was performed, a pattern profile close to vertical having a high precision without Scum was possible. However, in the case of FIG. It was confirmed that scum 7 was generated due to the neutralization of the strong acid in the portion where the resist film was to be removed due to exposure at the interface of the mask film. In addition, it was confirmed that the pattern profile also has a wide pattern rather than vertical, resulting in poor pattern precision. Therefore, it was confirmed that the CD of the final photomask was also deteriorated due to the inferior precision of the resist pattern.

In the above embodiment, the surface treatment is performed on the hard mask film containing essentially nitrogen to obtain a precise pattern when the chemically amplified resist is applied. However, the surface treatment is performed even if the hard mask film does not necessarily contain nitrogen. It is preferable. Even if the hard mask film does not contain nitrogen, which is the cause of the substrate dependency, the strong acid may diffuse into the hard mask film or may be lost, thereby reducing the precision of the chemically amplified resist pattern. In addition, the adhesion may be improved by performing the surface treatment. Therefore, it is preferable to perform surface treatment even if it does not necessarily contain nitrogen.

(Example 5)

This embodiment is an example in which there is no etch stop layer.

First, a light shielding film having a MoSiN composition was formed to a thickness of about 30 nm through DC magnetron sputtering using a single target having a Mo: Si composition of 10:90 at% on the substrate. At this time, the thickness can be selectively formed at a thickness of 10 to 40nm. Moreover, you may form in the form which has not only MoSiN but MoSi, MoSiC, MoSiCN composition.

Next, using a single target having a Mo: Si composition of 10:90 at%, DC magnetron sputtering was performed to form an antireflection film having a MoSiCON composition with a thickness of 15 nm. In this case, the antireflection film may be selectively formed in one form selected from MoSiN, MoSiCN, MoSiO, and MoSiCO.

After forming a light shielding film of MoSiN and an antireflection film of MoSiCON on a transparent substrate, a hard mask film made of Cr was formed to a thickness of 10 nm. The hard mask film was formed of a chromium target through a DC magnetron sputtering method. At this time, the hard mask film may be one selected from Cr alone, CrC, CrO, CrN, CrCN, CrCO, CrCON or Ta alone, TaC, TaO, TaN, TaCO, TaCN, TaCON.

At this time, as a result of analyzing the composition ratio of the thin film by x-ray photoelectron spectroscopy (XPS), the composition of Mo: Si: N was analyzed as 11.8at%: 59.2at%: 29at% in the case of light shielding film. In the case of Mo: Si: C: O: N, the composition of 10.4at%: 58.3at%: 1.2at%: 1.6at%: 28.5at% was analyzed. In the case of the hard mask film, it was analyzed with 100at% of chromium.

Next, HMDS (hexamethyl disiloxane) was treated on the surface of the hard mask film on a hot plate of 150 degrees, and a chemically amplified resist was formed to a thickness of 150 nm to manufacture a blank mask.

Using a blank mask manufactured through the above process, a CAR was exposed through a 50 kV electron beam exposure apparatus, and a resist pattern was formed through a general phenomenon through a PEB process.

Next, a dry etching process of a hard mask film having a composition of Cr was performed using the resist pattern as a mask. At this time, the hard mask film dry etching was performed by mixing chlorine and oxygen gas through an inductively coupled plasma (ICP) etching method.

Next, the unnecessary resist pattern was removed by washing with ozone water. Next, the hard mask pattern was masked, and SF ₆ , which is a fluorine-based gas, and oxygen gas were mixed, and dry etching was performed on the antireflection film and the light shielding film through ICP etching. At this time, the fluorine-based gas such as SF ₆ , CF ₄ , C ₄ F _4, etc. also damages the transparent substrate (quartz substrate) at the bottom of the shielding film. Detection was performed to adjust the etching time to minimize damage to the transparent substrate. In order to prevent damage to the transparent substrate, damage to the transparent substrate is prevented by forming an etch stop layer mainly composed of a transition metal such as Cr or Ta, which is not etched in the fluorine-based gas or has a slow etching rate, between the shading film and the transparent substrate. It is also possible to prevent.

Next, chlorine-based gas and oxygen gas were mixed to perform ICP etching to remove the hard mask pattern to prepare a photomask. At this time, the chlorine-based gas does not damage the antireflection film and the transparent substrate having the composition of MoSiCON.

Next, CD measurements were carried out through CD SEM. As a result of the measurement of the line circuit in the 50 nm line and space circuit, the MTT (mean to target) was 3 nm or less, CD uniformity was 2.4 nm or less, and iso dense. It was confirmed that the high-density photomask that can realize 22nm-class optical proximity correction (OPC) pattern formation was shown by showing excellent CD characteristics with a bias of 2.1 nm and 1.2 nm of LER. This can be achieved because the density of the thin film is all 2 g / cm 3 and the crystallization state of the thin film is amorphous.

In this embodiment, a blank mask was manufactured by forming a MoSiN light blocking film, a MoSiCON anti-reflection film, and a Cr hard mask film on a transparent substrate without an etch stop film, but various embodiments of the present invention may be modified. Modifications can be made in various forms, such as the formation or absence of an etch-stop film based on transition metals such as Cr and Ta, a MoSi light-shielding film and a MoTaSi-based anti-reflection film, a MoTaSi-based light-shielding film, and a MoSi-based anti-reflection film. In addition, the hard mask film may be modified by using various transition metals such as Ta, W, Hf, Zr, Ti, etc., as well as Cr.

(Example 6)

The following is an embodiment using a MoSi target as a single layer metal film and a Cr target as a hard mask material.

A single layer metal film was deposited on a 6-inch by 6-inch by 0.25-inch synthetic quartz substrate using a MoSi target having a composition ratio of 10:90 at% molybdenum: silicon. At this time, the deposited thin film was applied with DC Magnetron Sputtering method. The power of 570W and the pressure of 1.5mtorr were applied to human DC power under argon (Ar): nitrogen (N ₂ ) = 80sccm: 20sccm. Laminated to thickness. The thickness of the metal film is not limited to 50 nm, and may be formed at a thickness of 20 to 80 nm, the power is 0.1 to 5 kW, the pressure is 0.1 mtorr to 10 mtorr, the reactive gas also has argon 10 to 100 sccm, nitrogen 10 to 10 It is possible to change to 90 sccm, and as the reactive gas, argon alone or methane, carbon dioxide and oxygen may be added.

As a result of optical property evaluation of the metal film, the optical density was measured at 2.93 at the surface of the metal film at 193 nm, which is an ArF exposure wavelength, and the reflectance at the metal film surface was measured at 21.2% at 193 nm, thus having no problem in optical density and reflectance.

In order to evaluate the chemical resistance of the metal film to chemicals, after immersion for 2 hours in sulfuric acid at 80 degrees, SC 1 at 23 degrees and CR-7S, a chromium etchant for 2 hours, the change in transmittance at 193 nm was observed. The transmittance change of 0.23% for 1, 0.01% for CR-7S, and 0.12% for NaOH showed excellent chemical resistance.

Then, a hard mask film of chromium carbide oxynitride (CrCON) was laminated on the formed metal film under a gas condition of chromium (Cr) target and argon: nitrogen: methane: oxygen = 20sccm: 60sccm: 1sccm: 1.25sccm. Subsequently, sheet resistance was measured by using a 4-point probe to determine whether there is a charge-up problem during the exposure of the E-beam on the surface of the hard mask layer. As a result of measuring the sheet resistance, 220 Ω / □ was shown on the surface of the hard mask film.

After that, exposure, PEB and development were carried out using an E-beam Writer having an acceleration voltage of 50 keV, and then the dry mask was etched using a resist mask as a pattern mask with a Cl ₂ gas of 40 sccm, a power of 400 W, and a pressure of 5 mtorr. The resist was removed. Subsequently, dry etching was performed using a hard mask film of CrCON as a mask pattern with MoSiN serving as a metal film, 80 sccm of CF ₄ gas, 500 W of power, and 5 mtorr of pressure. Thereafter, the remaining hard mask film was removed using CR-7S to prepare a photomask. CD measurements were performed on the finished photomask using CD-SEM. As a result of measuring the line circuit in the 50nm line / space circuit, MTT was 2.7 nm, CD uniformity was 2.2 nm, and iso dense bias was 2.0 nm and LER showed excellent CD characteristics of 1.1 nm, making it possible to manufacture high-precision photomasks that can implement 22 nm-class optical proximity correction pattern formation.

The blank mask composed of the single layer metal film and the hard mask film is not limited to the MoSiN metal film, but may be applied to various types of MoSi compounds using MoSi, that is, MoSi, MoSiC, MoSiO, MoSiCO, MoSiON, MoSiCON. In addition, it can be seen that due to the high extinction coefficient of MoSi satisfies the optical properties even at a lower thickness than the conventional metal film. Therefore, it can be seen that the resulting loading effect is reduced to show excellent MTT and uniformity values. In addition, the above-described embodiment formed of a single-layer metal film may be configured not only as a single film but also as a two-layer film or a two-layer film or more. In the case of MoSiN serving as a single-layer metal film, not only two-layer films such as MoSi / MoSiN, MoSi / MoSiCN, MoSi / MoSiON, but also multi-layer films of MoSi / MoSiN / MoSiON can be implemented. In addition, CrCON used as a hard mask film is not limited to CrCON, but may be applied in the form of Cr, CrC, CrN, CrO, CrON, CrCO, CrCN.

(Example 7)

In the seventh embodiment, MoSi is used as the single layer metal film and Ta is applied as the hard mask film based on the sixth embodiment.

As in Example 6, a MoSiCN film was formed by controlling a reactive gas with a single film metal film. At this time, the MoSiCN film was deposited at a power of 1.3 kW and a pressure of 1.5 mtorr. At this time, a reactive gas was formed to a thickness of 50 nm under a condition of argon: nitrogen: methane = 20 sccm: 80 sccm: 0.3 sccm. The thickness of the metal film is not limited to 50 nm, and may be formed at a thickness of 20 to 80 nm, the power is 0.1 to 5 kW, the pressure is 0.1 mtorr to 10 mtorr, and the reactive gas is also argon 10 to 100 sccm, nitrogen 10 to 10 It is possible to change to 90 sccm, and as the reactive gas, argon alone or methane, carbon dioxide and oxygen may be added.

As a result of measuring the optical properties of the metal film, the optical density was measured to be 2.83 at the surface of the metal film at 193 nm, which is an ArF exposure wavelength, and the surface reflectance of the metal film was measured at 20.9% at 193 nm, so there was no problem in optical density and reflectance. . As a result of chemical resistance evaluation for sulfuric acid, SC 1, NaOH for the evaluation of chemical resistance, it was found that the chemical resistance was excellent by showing a change in transmittance of 0.19% in sulfuric acid, 0.32% in SC 1, and 0.10% in NaOH.

After that, a tantalum (Ta) target and a hard mask film of tantalum nitride (TaN) were stacked to a thickness of 10 nm under a gas condition of argon: nitrogen = 60 sccm: 40 sccm. Subsequently, sheet resistance was measured by using a 4-point probe to determine whether there was a charge-up problem when the E-beam was exposed on the surface of the hard mask layer. The sheet resistance was 240 kV / square, indicating no abnormality.

Next, after forming the hard mas film of chromium and tantalum, the surface treatment was performed at 400 ° C./20 minutes at a vacuum degree of 1 × 10 ⁻⁶ torr using a vacuum hot plate. This is to obtain high quality CD by forming excellent pattern profile through scum prevention by Substrate dependency when forming pattern using chemically amplified resist.

Next, a blank mask was prepared by spin coating each of FEP-171, a positive chemically amplified photoresist (CAR) for an electron beam exposure apparatus, to a thickness of 150 nm and performing a soft bake. .

After the exposure using a 50keV E-beam Writer, PEB and development were performed. Thereafter, using the resist film as a pattern mask, the hard mask film of tantalum nitride was dry etched at Cl ₂ = 80 sccm, power 400W, and pressure 5 mtorr, and then the resist was removed. Subsequently, the MoSiCN film of the metal film was dry-etched under the condition of CF ₄ = 80 sccm, power 400 W, and pressure 5 mtorr, using the tantalum nitride hard mask film as a mask pattern. After removing the tantalum nitride as a hard mask using a NaOH solution to prepare a photomask. In this case, the hard mask removal may be performed by dry removal using Cl ₂ gas as well as wet removal including NaOH. After that, CD was measured by CD SEM to evaluate the performance of the manufactured photomask. In the 50nm line / space circuit, MTT was 2.6nm, CD Uniformity was 2.0nm and iso dense. The CD characteristics were excellent with a bias of 1.8 nm and LER of 1.0 nm.

The blank mask composed of the single layer metal film and the hard mask film is not limited to the MoSiCN metal film, but may be applied to various types of MoSi compounds using MoSi, that is, MoSi, MoSiC, MoSiO, MoSiCO, MoSiON, and MoSiCON. In addition, it can be seen that due to the high extinction coefficient of MoSi satisfies the optical properties even at a lower thickness than the conventional metal film. Therefore, it can be seen that the resulting loading effect is reduced to show excellent MTT and uniformity values. In addition, the above-described embodiment formed of a single-layer metal film may be configured not only as a single film but also as a two-layer film or a two-layer film or more. In the case of MoSiCN serving as a single-layer metal film, not only two-layered films such as MoSi / MoSiN, MoSi / MoSiCN, MoSi / MoSiON, but also multi-layered films of MoSi / MoSiN / MoSiON can be implemented. In addition, TaN used as a hard mask film is not limited to TaN, but may be applied in the form of Ta, TaC, TaO, TaON, TaCO, TaCN, TaCON.

(Example 8)

Example 8 is an example of a structure in which the metal film of Example 6 is formed using a MoTaSi target.

First, a single-film metal film was deposited on a 6-inch by 6-inch by 0.25-inch synthetic quartz substrate using a MoTaSi target having a composition ratio of molybdenum: tantalum: silicon = 5: 5: 90 at%. At this time, DC Magnetron Sputtering method was applied, and the power was 350W and the pressure was 1.5mtorr, and argon (Ar): Nitrogen (N ₂ ) = 80sccm: 20sccm was applied to human DC power, and MoTaSiN was 45nm. Laminated to thickness. The thickness of the metal film is not limited to 45 nm, and may be formed at a thickness of 20 to 80 nm, the power is 0.1 to 5 kW, the pressure is 0.1 mtorr to 10 mtorr, the reactive gas is also argon 10 to 100 sccm, nitrogen 10 to 10 It is possible to change to 90 sccm, and as the reactive gas, argon alone or methane, carbon dioxide and oxygen may be added.

As a result of measuring the optical properties of the metal film, the optical density was measured at 3.0 at the surface of the metal film at 193 nm, which is an ArF exposure wavelength, and the reflectance at the metal film surface was measured at 23.2% at 193 nm. there was no problem. In order to evaluate the chemical resistance of the metal film to chemicals, after immersion for 2 hours in sulfuric acid at 80 degrees, SC 1 at 23 degrees and CR-7S chromium etchant for 2 hours, the change in transmittance at 193 nm was 0.07% in sulfuric acid, SC The transmittance change of 0.13% for 1 and 0.01% for CR-7S was found to be excellent in chemical resistance.

Next, a chromium (Cr) target and a hard mask film of chromium carbide oxynitride (CrCON) were laminated to a thickness of 10 nm under a gas condition of chromium (Cr) target and argon: nitrogen: methane: oxygen = 20sccm: 60sccm: 1sccm: 1.25sccm. Subsequently, sheet resistance was measured using a 4-point probe to determine whether there was a charge-up problem when the E-beam was exposed on the surface of the hard mask layer. The sheet resistance was 207 kW / square, indicating no abnormality.

Thereafter, an E-beam Writer having an acceleration voltage of 50 keV was used for exposure, PEB, and development, followed by dry etching of the hard mask film and removal of the resist. Thereafter, the metal film was dry-etched using CHF ₄ and O ₂ gas using the hard mask film of CrCON as a mask pattern. After that, the remaining hard mask film was removed using CR-7S to complete the photomask. CD measurements were performed on the finished photomask using CD-SEM. As a result of measuring the line circuit in the 50nm line / space circuit, MTT was 2.5nm, CD uniformity was 2.0nm, and iso dense bias was 1.7 nm, LER of 0.7nm showed excellent CD characteristics, it can be seen that the production of high-precision photomask is possible.

The blank mask composed of the single-layer metal film and the hard mask film is not limited to the MoTaSiN metal film, but also applied to various forms of the compound of MoTaSi using MoTaSi, that is, MoTaSi, MoTaSiC, MoTaSiO, MoTaSiCO, MoTaSiON, and MoTaSiCON. It can be seen that, due to the high extinction coefficient of MoTaSi, it satisfies the optical properties even at a lower thickness than the conventional metal film. Therefore, it can be seen that the resulting loading effect is reduced to show excellent MTT and uniformity values. In addition, the above-described embodiment formed of a single-layer metal film may be configured not only as a single film but also as a two-layer film or a two-layer film or more. MoTaSiN, which serves as a single-layer metal film, may be implemented in a multi-layered film such as MoTaSi / MoTaSiN / MoTaSiON as well as a two-layered film such as MoTaSi / MoTaSiN, MoTaSi / MoTaSiCN, MoTaSi / MoTaSiON. In addition, CrCON used as a hard mask film is not limited to CrCON, but may be applied in the form of Cr, CrC, CrN, CrO, CrON, CrCO, CrCN.

(Example 9)

Example 9 is an example of using a tantalum (Ta) target as a hard mask layer on a single layer metal layer using a MoTaSi target based on Example 8.

In Example 9, a MoTaSiCN film was formed by controlling a reactive gas with a single film metal film in the same manner as in Example 8. At this time, the MoTaSiCN film was deposited at a power of 0.75 kW and a pressure of 1.5 mtorr, and a reactive gas was formed at a thickness of 45 nm under the conditions of argon: nitrogen: methane = 80 sccm: 20 sccm: 0.5 sccm. The thickness of the metal film is not limited to 45 nm, and may be formed at a thickness of 20 to 80 nm, the power is 0.1 to 5 kW, the pressure is 0.1 mtorr to 10 mtorr, the reactive gas is also argon 10 to 100 sccm, nitrogen 10 to 10 It is possible to change to 90 sccm, and as the reactive gas, argon alone or methane, carbon dioxide and oxygen may be added.

As a result of measuring the optical properties of the deposited metal film, the optical density was measured to be 2.92 at the surface of the metal film at 193 nm, which is an ArF exposure wavelength, and the surface reflectance of the metal film at 193 nm was measured at 21.3%, resulting in problems in optical density and reflectance. There was no. Similarly, the chemical resistance evaluation of sulfuric acid, SC 1 and NaOH for the evaluation of chemical resistance showed that the permeability changes of 0.15% in sulfuric acid, 0.22% in SC 1, and 0.11% in NaOH.

After that, a tantalum (Ta) target and a hard mask film of tantalum nitride (TaN) were stacked to a thickness of 10 nm under a gas condition of argon: nitrogen = 60 sccm: 40 sccm. Subsequently, sheet resistance was measured by using a 4-point probe to determine whether there was a charge-up problem when the E-beam was exposed on the surface of the hard mask layer. Sheet resistance was not a problem for use at 252 kV / square.

Next, after forming the hard mas film of chromium and tantalum, the surface treatment was performed at 400 ° C./20 minutes at a vacuum degree of 1 × 10 ⁻⁶ torr using a vacuum hot plate. Thereafter, FEP-171, a positive chemically amplified photoresist (CAR) for an electron beam exposure apparatus, was spin-coated to a thickness of 150 nm and soft baked to prepare a blank mask. .

After the exposure using a 50keV E-beam Writer, PEB and development were performed. Thereafter, the hard mask film of tantalum nitride was dry-etched using Cl ₂ gas to remove the resist. Subsequently, the MoTaSiCN film of the metal film was dry-etched under the condition of CF4 = 80 sccm, 500 W, and 5 mtorr using the hard mask film of tantalum nitride as a mask pattern. Thereafter, tantalum nitride was removed using a NaOH solution to prepare a photomask. At this time, dry etching using Cl2 gas may be used to remove the hard mask TaN. After the measurement of CD through CD SEM for performance evaluation of the manufactured photomask, in the 50nm line / space circuit, MTT was 2.2nm, CD Uniformity was 1.8nm and iso dense bias as a result of measuring the line circuit. Was 1.6 nm and LER was 1.0 nm, which showed excellent CD characteristics.

The blank mask composed of the single-layer metal film and the hard mask film is not limited to the MoTaSiN metal film, but also applied to various forms of the compound of MoTaSi using MoTaSi, that is, MoTaSi, MoTaSiC, MoTaSiO, MoTaSiCO, MoTaSiON, and MoTaSiCON. It can be seen that, due to the high extinction coefficient of MoTaSi, it satisfies the optical properties even at a lower thickness than the conventional metal film. Therefore, it can be seen that the resulting loading effect is reduced to show excellent MTT and uniformity values. In addition, the above-described embodiment formed of a single-layer metal film may be configured not only as a single film but also as a two-layer film or a two-layer film or more. MoTaSiN, which serves as a single-layer metal film, may be implemented in a multi-layered film such as MoTaSi / MoTaSiN / MoTaSiON as well as a two-layered film such as MoTaSi / MoTaSiN, MoTaSi / MoTaSiCN, MoTaSi / MoTaSiON. In addition, TaN used as a hard mask film is not limited to TaN, but may be applied in the form of Ta, TaC, TaO, TaON, TaCO, TaCN, TaCON.

(Example 10)

Example 10 shows an example of a structure in which an etch stop layer, a metal layer, and a hard mask layer are formed.

The etch stop layer is to minimize the damage of the substrate caused by the hydrofluoric acid gas used in the dry etching due to the Si component contained in the metal film. For this purpose, the etch stop layer is not etched by the hydrofluoric acid gas and chlorine gas. It must have the property of being etched by. Therefore, Cr and Ta compounds which were not etched in the hydrofluoric acid-based gas were used as the etch stop layer.

First, the result of applying the Cr compound as an etch stop layer will be described.

First, using a Cr target as an etch stop layer, argon: nitrogen: methane = 80sccm: 10sccm: 1sccm was deposited at a power of 100W to a thickness of 65 kPa at 1.5 mtorr. At this time, the O.D of the etch stop layer showed 0.26 at 193 nm. Afterwards, in consideration of the OD of the etch stop layer, using a MoSi target of molybdenum: silicone = 10: 90at% as a metal film, 500W of power in a gas atmosphere of argon: nitrogen = 80: 20sccm and a pressure of 42nm at 1.5mtorr were used. It was formed into a thickness. At this time, the O.D at 193 nm on the surface of the metal film on which the etch stop film metal film was laminated was measured to be 3.1, and the reflectance was 22.30%. Thereafter, a reactive gas was formed by using a Cr target to form a hard mask film using argon: nitrogen: carbon dioxide = 20sccm: 60sccm: 1.25sccm, power 470W, and pressure 1.5mtorr at a thickness of 11 nm. As a result of measuring the sheet resistance on the surface of the hard mask layer using the Point Probe, it was confirmed that the level of 189Ω / □ could prevent the charge-up phenomenon that may occur during E-beam writing. Thereafter, surface treatment was performed using vacuum hot-plate for 400 ° C./20 minutes. Thereafter, FEP-171, a chemically amplified resist, was spin-coated with a thickness of 150 nm, followed by soft baking.

After the exposure, PEB and development were performed using an E-beam Writer with an accelerating voltage of 50 keV to fabricate the photomask.The hard mask layer was dry-etched under 80 sccm of Cl ₂ gas, 400 W of power, and 5 mtorr of pressure. The chemically amplified resist was removed again, and the metal film was dry etched using the hard mask as a mask. At the time of dry etching, the selectivity of the hard mask film and the metal film was measured by V-SEM. As a result, the selectivity of the hard mask film was 15 or more. In addition, as a result of measuring the selectivity with the etch stop layer by V-SEM in the dry etching of the metal film, the selectivity was 20 or more.

Afterwards, the photomask was completed by simultaneously removing the etch stop layer and the hard mask layer using CR etchant, CR-7S. In this case, the etching stop layer and the hard mask layer may be wet-etched using CR-7S as well as dry etching using Cl ₂ gas, which is a chlorine gas.

Afterwards, CD measurement was performed through CD-SEM to evaluate the performance of the finished photomask. As a result of measuring the line circuit in the 50nm line / space circuit, MTT was 2.6nm, CD Uniformity was 2.1nm, and iso dense bias. Is 2.2nm, LER is 1.4nm, showing excellent CD characteristics, it can be seen that high-precision photomask production is possible.

The present embodiment is not limited to the etch stopper film and the hard mask film of the Cr compound, but may be composed of the etch stopper film and the hard mask film of the Ta compound, and the hard stop of the etch stopper film and the Ta compound of the Cr compound. It may also consist of a mask film. In addition, a Cr compound is not limited to CrCN in a present Example. It may be formed of Cr, CrC, CrN, CrO, CrCO, CrCN, CrCON Cr compound, Ta compound may also be composed of Ta, TaN, TaC, TaO, TaCO, TaCN, TaCON.

1A to 1G are diagrams schematically showing one embodiment of a blank mask and a photomask according to the present invention.

2 is a table schematically showing an embodiment of a blank mask and a photo mask according to the present invention.

3 is a table schematically showing an embodiment of a blank mask and a photo mask according to the present invention.

4A and 4B are diagrams schematically showing a resist pattern profile according to the surface treatment of the present invention.

<Brief description of the main parts of the drawing>

1: transparent substrate 2: etch stop film

3: shading film 4: anti-reflection film

5: hard mask film 6: chemically amplified resist

7: scum 100: blank mask

200: photomask

Claims (39)

In a blank mask in which a metal film, a hard mask film, and a resist film are sequentially formed on a transparent substrate, The crystallization state of the hard mask film is an amorphous state, The hard mask film has a density of 2 g / cm 3 or more, The hard mask film is a blank mask, characterized in that formed using a target manufactured by HIP (hot iso-static pressing) method. The method of claim 1, The blank mask, characterized in that the etch stop layer is further formed between the transparent substrate and the metal film. The method according to claim 1 or 2, The blank mask, characterized in that the metal film is a single film or two or more films. The method of claim 3, wherein If the metal film is a single film blank mask, characterized in that it comprises a function of the light shielding film that can block light with only a single film and the anti-reflection film to reduce the reflection of light. The method of claim 3, wherein The blank mask, characterized in that the metal film is composed of two or more layers of at least one light shielding film capable of shielding light, and at least one layer of anti-reflection film to reduce the reflection of light. The method according to claim 1 or 2, The resist film is formed by coating a chemically amplified resist, A blank mask, characterized in that the surface treatment to reduce the substrate-dependent phenomenon of the chemically amplified resist before the chemically amplified resist coating on the surface of the hard mask film. The method according to claim 1 or 2, The hard mask film is Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Hf, Ta, A blank mask comprising at least one metal selected from W, Os, Ir, Pt and Au. The method of claim 7, wherein The blank mask is a blank mask, characterized in that the metal is used alone or in the form of one type selected from oxides, carbides, nitrides, oxidized carbides, oxynitrides, carbides, oxynitrides of the metal. The method of claim 8, When the hard mask film is in the form of a compound mainly containing Cr or Ta, A blank mask comprising a composition of Cr or Ta of 30 to 70 at%, carbon of 0 to 30 at%, oxygen of 0 to 20 at%, and nitrogen of 0 to 40 at%. The method of claim 2, The etch stop layer includes Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Hf, Ta, A blank mask comprising at least one metal selected from W, Os, Ir, Pt and Au. The method of claim 10, The etch stop layer is used as the metal alone or a blank mask, characterized in that one type selected from oxides, carbides, nitrides, oxidized carbides, oxynitrides, carbonitrides, oxynitrides. The method of claim 11, When the etch stop layer is in the form of a compound containing Cr or Ta as a main component, Blank mask characterized in that it contains 30 to 90 at% of Cr or Ta, 0 to 30 at% of carbon, 0 to 10 at% of oxygen, and 0 to 60 at% of nitrogen. The method according to claim 1 or 2, The blank mask, characterized in that the thickness of the etch stop layer or hard mask layer 3 ~ 30nm. The method of claim 2, The blank mask, characterized in that the thickness of the etch stop layer is thicker than the thickness of the hard mask layer. The method of claim 2, The blank mask, characterized in that the etching rate of the wet or dry etching of the etch stop layer is faster than the etching rate of the hard mask layer. The method according to claim 1 or 2, The metal mask is a blank mask, characterized in that the composition consisting essentially of one or more metals and silicon. The method according to claim 1 or 2, The metal film is made of at least one metal and silicon, or a blank mask, characterized in that one type selected from oxides, nitrides, carbides, oxynitrides, oxidized carbides, carbides. The method according to claim 1 or 2, The metal film essentially includes at least one metal and silicon, The metal is Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Hf, Ta, W Blank mask characterized in that it contains one or two or more selected from Os, Ir, Pt, Au. The method according to claim 1 or 2, The metal film is composed of a lower layer serving as a light shielding film, and an upper layer serving as an antireflection film. The lower layer is a blank mask, characterized in that made of only MoSi containing 20 to 70 at% Mo, 30 to 70 at% Si. The method according to claim 1 or 2, The metal film is composed of a lower layer and an upper layer made of MoSi compound, The lower layer serves as a light shielding film, the upper layer serves as an antireflection film, The lower layer is a blank mask, characterized in that it comprises a composition of Mo 1 ~ 20at%, Si 40 ~ 80at%, nitrogen 10 ~ 50at%, carbon 0 ~ 10at%. The method of claim 20, The upper layer is a blank mask, characterized in that it comprises a composition of 1 to 20 at% Mo, 40 to 80 at% Si, 0 to 10 at% oxygen, 10 to 50 at% nitrogen, 0 to 10 at% carbon. The method according to claim 1 or 2, The metal film is composed of a lower layer serving as a light shielding film and an upper layer serving as an antireflection film, The lower layer is a blank mask, characterized in that made of MoTaSi containing a composition of 10 to 60 at% Mo, 2 to 30 at% Ta, 30 to 70 at% Si. The method according to claim 1 or 2, The metal film is composed of a lower layer and an upper layer made of a MoTaSi compound, The lower layer serves as a light shielding film, the upper layer serves as an antireflection film, The lower layer is a blank mask, characterized in that it comprises a composition of 1 to 15 at% Mo, 1 to 15 at% Ta, 40 to 80 at% Si, 10 to 50 at% nitrogen, 0 to 10 at% carbon. The method according to claim 1 or 2, The metal film is composed of a lower layer and an upper layer made of a MoTaSi compound, The lower layer serves as a light shielding film, the upper layer serves as an antireflection film, The upper layer has a composition of 1 to 15 at% Mo, 1 to 15 at% Ta, 40 to 80 at% Si, 0 to 10 at% oxygen, 10 to 50 at% nitrogen, and 0 to 10 at% carbon. Blank mask made with. The method according to claim 1 or 2, When the metal film is composed of a two-layer film, The lower layer from the substrate is composed of a light shielding film essentially including MoSi, The blank mask, characterized in that the upper layer is made of an anti-reflection film essentially containing MoTaSi. The method according to claim 1 or 2, When the metal film is composed of a two-layer film, The lower layer from the transparent substrate is composed of a light shielding film essentially containing MoTaSi, The blank mask, characterized in that the upper layer is made of an anti-reflection film essentially containing MoSi. The method according to claim 1 or 2, The etch stop layer or the hard mask layer is not dry etched in the fluorine-based gas, is etched in the chlorine-based gas, The blank mask, characterized in that the metal film formed directly on the transparent substrate or the etch stop film is not etched by the chlorine-based gas for etching the etch stop film. The method according to claim 1 or 2, The metal film may be dry etched by the fluorine-based gas and not etched by the chlorine-based gas. The blank blocking film or the hard mask film is a blank mask, characterized in that the etching by the fluorine-based gas for etching the metal film. The method according to claim 1 or 2, The hard mask layer is not dry etched by fluorine-based gas, is etched by chlorine-based gas, The blank mask, characterized in that the metal film formed directly below the hard mask film is not etched by the chlorine-based gas for etching the hard mask film. The method of claim 2, And when the hard mask layer is etched by the chlorine-based gas, the etch stop layer is etched simultaneously. The method according to claim 1 or 2, And the optical density of the metal film is 2.5 or more at an exposure wavelength of 193 nm. The method according to claim 1 or 2, A blank mask, wherein said metal film has a thickness of 500 kPa or less. The method according to claim 1 or 2, And a reflectance of said metal film is 25% or less at an exposure wavelength of 193 nm. The method of claim 6, The surface treatment is characterized in that the heat treatment, the heat treatment method for the surface treatment is a hot plate (Hot-plate), vacuum hot plate (Vacuum Hot-plate), vacuum oven (Vacuum Oven), vacuum chamber (Vacuum) Blank), characterized in that the mask made through a method selected from the (Furnace). The method of claim 34, When the heat treatment for the surface treatment is carried out through a lamp, characterized in that carried out through one or more methods selected from Rapid Thermal Process (RTP), heating wire, ultraviolet lamp (Lamp), halogen (Halogen) lamp Blank Mask. The method of claim 34, The surface treatment is to perform the surface treatment through a liquid or gas containing silicon in addition to the heat treatment, The media essentially containing silicon include hexamethyldisilane, trimethylsilyl diethylamine, O-trimethylsilyl-acetate, and O-trimethylsilylproprionate (O- trimethylsilylproprionate, O-trimethylsilylbutyrate, Trimethylsilyltrifluoroacetate, Trimethylmethoxysilane, N-methyl-N-trimethylsilyltrifluoroacetamide (N-methyl-trimethyl) N-trimethyl-silyltrifluoroacetamide, O-trimethylsilylacetylacetone, Isopropenoxytrimethylsilane, Trimethylsilyltrifluoroacetamide, Methyltrimethylsilyldimethylketone acetate , Trimethylethoxysilan Blank mask, characterized in that carried out by applying one or two or more materials selected from. In the manufacturing method of the blank mask for manufacturing the blank mask of Claim 1 or 2, A method of manufacturing a blank mask comprising forming a metal film, a hard mask film, and a resist film on a transparent substrate. A photomask manufactured by using the blank mask of claim 1, wherein the hardmask film is etched using a resist film patterned by exposing and developing the resist film, And the metal film is etched using the etched hard mask film as a mask. Preparing the blank mask of claim 1; Exposing and developing the resist film to form a resist film pattern; Etching the hard mask film using the resist film pattern as a mask; And Etching the metal film using the etched hard mask film as a mask.

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