KR20080017785A - Cluster type blank mask and its manufacturing process and manufacturng method of photomask thereby - Google Patents

Abstract

A cluster type blank mask, a method for manufacturing blank, and photo masks are provided to reduce scum in photo mask manufacturing by controlling ammonia on photoresist. An anti-reflective coating layer(6) and/or a light shielding layer(4) are stacked on a transparent substrate(2) using reactive sputtering and vacuum depositing schemes so as to improve the particles of a metal layer. Resists are coated on the anti-reflective coating layer and/or light shielding layer. The anti-reflective coating layer and light shielding layer are formed based on a metal in a vacuum chamber used inert gas and reactive gas using reactive sputtering and vacuum depositing schemes. The metal is at least one selected from a group consisting of Co, Ta, W, Mo, Cr, V, Pd, Ti, Nb, Zn, Hf, Ge, Al, Pt, Mn, Fe, Si, Ni, Cd, Zr, Mg, Li, Se, Cu, Y, and S. The inert gas is at least one selected from a group consisting of Ar, He, Ne, and Xe. The reactive gas is at least one selected from a group consisting of O2, CO, CO2, N2O, NO, NO2, NH3, CH4, and F.

Description

Cluster Type Blank Mask and Its Manufacturing Process and Manufacturng Method of Photomask Thereby}

1 is a schematic diagram of a cluster device according to the present invention.

2 is a cross-sectional process diagram schematically showing an embodiment of a method of manufacturing a binary blank mask according to the present invention.

According to the present invention, as the critical dimension of the pattern of the semiconductor integrated circuit becomes finer and more highly integrated, it is necessary to control particles that may affect the process. Such particulates may occur in the photomask manufacturing process or the blank mask manufacturing process.

As the product defect rate increases due to the fine particles during photomask manufacturing, production efficiency decreases. Therefore, in order to solve these problems, it is necessary to control the fine particles generated in the photomask manufacturing process, and to minimize the fine particles of the blank mask used for the photomask manufacturing. Should be.

In the in-line method of manufacturing a generally-used binary blank mask, it is difficult to control fine particles because there are many rotating and moving parts. There is a problem.

Accordingly, the present invention provides a cluster method that makes it easier to control fine particles, and selectively heat-treats to improve adhesion and growth of the metal film before and after forming the metal film, and at the same time, improve the resistance to chemicals. The present invention provides a blank mask and a blank mask and a photomask manufacturing method therefor.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a binary blank mask and a photomask, and inerts a metal or metal-containing target on a transparent substrate, and argon (Ar), helium (He), neon (Ne), and xeon (Xe). Gas, carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen monoxide (NO), nitrogen dioxide (N ₂ O), nitrous oxide (NO ₂ ), oxygen (O ₂ ), nitrogen (N ₂ ), fluorine (F) And at least one or more active gases such as methane (CH ₄ ) or ammonia (NH ₃ ) are mixed at a constant partial pressure ratio to form a metal mask continuously or sequentially by reactive sputtering and its preparation It includes a method.

In addition, in the present invention, the internal stress due to the formation of a thin film is alleviated by oxidizing, nitriding, or carbonizing or fluorinating the surface of the metal film by heat treatment under vacuum or atmospheric pressure under a controlled gas atmosphere, thereby reducing substrate flatness and improving surface film characteristics In particular, in the case of the anti-reflection film, a binary blank mask coated with a chemically amplified resist (CAR) is coated by improving adhesion to the photoresist and controlling ammonia (NH ₃ ) on the surface. Provided are a method of manufacturing a binary blank mask that can reduce a scum in manufacturing a photomask to be used.

In the present invention, the in-line method has a high throughput in the manufacturing method of the binary blank mask, but since there are many parts constituting the conveying system, the defects are high because the particles are continuously generated. have. On the other hand, in the case of the cluster method, the production amount is lower than that of the inline method, but since the transport system is relatively small, it is easy to control the fine particles and has an advantage of easily forming a multilayer film.

An object of the present invention is to control the fine particles generated due to the in-line transport system, and to improve the adhesion and growth of the metal film before and after forming the metal film, and to improve the resistance to chemicals (selective) It relates to a cluster method that is easy to heat treatment.

  In addition, another object of the present invention is to perform heat treatment in a controlled gas atmosphere, thereby oxidizing, nitriding, carbonizing, or fluorinating the surface of the metal film, thereby relieving internal stress due to the formation of a thin film, thereby reducing substrate flatness. Binaries that can control film properties, especially anti-reflective films, improve adhesion to photoresist and control ammonia on the surface to reduce scum in photomask fabrication using binary blank masks coated with chemically amplified resists It is to provide a blank mask.

Binary blank mask manufacturing method proposed by the present invention in order to achieve the above object,

a1) forming a transparent substrate;

b1) forming a light shielding film on the transparent substrate formed in step a1);

c1) forming an anti-reflection film on the light shielding film formed in step b1);

d1) comprising applying a resist on the anti-reflection film formed in step c1).

The transparent substrate formed in step a1) is made of glass or quartz, and refers to a substrate having a transmittance of 90% or more.

The light shielding film formed in step b1) is formed using a reactive sputtering or vacuum deposition method in a vacuum chamber in which an inert gas and a reactive gas are introduced using a metal as a matrix.

Examples of the metal matrix used for forming the light shielding film include cobalt (Co), tantalum (Ta), tungsten (W), molybdenum (Mo), chromium (Cr), vanadium (V), palladium (Pd), and titanium (Ti). ), Niobium (Nb), zinc (Zn), hafnium (Hf), germanium (Ge), aluminum (Al), platinum (Pt), manganese (Mn), iron (Fe), silicon (Si), nickel (Ni ), Cadmium (Cd), zirconium (Zr), magnesium (Mg), lithium (Li), selenium (Se), copper (Cu), yttrium (Y), sulfur (S) It is used alone or as a compound.

At least one selected from argon (Ar), helium (He), neon (Ne), and xeon (Xe) is used as an inert gas for forming the light shielding film, and oxygen (O ₂ ), Nitrogen (N ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrous oxide (N ₂ O), nitrogen oxides (NO), nitrogen dioxide (NO ₂ ), ammonia (NH ₃ ), methane (CH ₄ ), fluorine At least 1 type is selected and used at (F).

When the metal matrix is chromium (Cr), chromium oxide (CrO), chromium nitride (CrN), chromium carbide (CrC), chromium carbide (CrCO), chromium nitride (CrCN), and chromium nitride (CrON) , Chromium oxynitride (CrCON), chromium fluoride (CrF), chromium fluoride (CrNF), chromium fluoride (CrOF), chromium fluorocarbon (CrCF), chromium fluoronitride (CrCNF), chromium oxynitride (CrONF ), A fluorocarbon oxynitride (CrCONF) is formed of a film of a component containing at least one or more.

The component content of the light shielding film composed of the film of the above components is 0 to 20 at% of carbon (C), 0 to 60 at% of oxygen (O), 0 to 60 at% of nitrogen (N), and 0 of fluorine (F). 40 at%, and the rest consists of chromium (Cr).

In the b1) step, the light shielding film has argon (Ar): nitrogen (N ₂ ): carbon dioxide (CO ₂ ): methane (CH ₄ ) under a condition that the vacuum degree of the vacuum chamber is 1 to 5 mTorr and the applied power is 0.5 to 2 kW. Is selected from 5 to 100 sccm: 10 to 95 sccm: 0 to 30 sccm: 0 to 30 sccm, and the mixing ratio of the inert gas and the active gas introduced into the vacuum chamber is 1 to 99.9%: 0.1 to 95 of the inert gas: active gas. It is preferable to set so that it may exist in% range, and to make it the film thickness to be 200-800 GPa.

The anti-reflection film formed in step c1) is formed of a film having a thickness of 50 to 400 kPa and differently selected from a kind and a ratio of reactive gases in order to lower the surface reflectivity under the light shielding film formation conditions of step b1).

In addition, in the steps b1) and c1), it is preferable to heat the substrate before and after the film formation to a predetermined temperature (about 80 to 500 ° C.) as a method for improving the adhesion and the growth of the film.

It is more preferable to perform annealing before and after film formation at a temperature of about 200 to 600 ° C. in order to control stress relief, etching characteristics, and surface residual ammonia concentration during vacuum deposition to 10 ppm, in particular, 2 ppm or less. Do. It is preferable that the mean square surface roughness (nmRMS) of the film formed here is 0.1-5 nm.

Moreover, it is preferable that surface reflectance in an exposure wavelength becomes 5 to 20%, and 8 to 15% is still more preferable.

Resist applied on the anti-reflection film in step d1), the optical photoresist THMR-iP3500, THMR-iP3600, DPR-i7000 and E-Beam resist EBR-9, PBS, ZEP- 7000, positive chemically amplified resists FEP-171, negative chemically amplified resists FEN-270, NEB-22, such as alkali-soluble resin and PAG (Photo Acid Generator), and the resist composition can be selected and used.

The resist to be coated on the antireflection film is applied by spin coating or capillary coating, and the thickness of the resist film is preferably maintained at about 1,000 to 6,000 Pa.

After applying the resist as described above, using a hot plate (Soft plate) in the temperature range of about 50 ~ 250 ℃ Soft Bake (Soft Bake) to prepare a blank mask according to the present invention.

Hereinafter, the present invention will be described in detail with reference to examples, but the examples are used only for the purpose of illustration and explanation of the present invention, and are used to limit the scope of the present invention as defined in the meaning or claims. no. Therefore, it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible from the embodiments. Therefore, the true technical protection scope of the present invention will be defined by the technical details of the claims.

EXAMPLE

1 is a schematic diagram of a cluster type sputtering apparatus for the present invention.

In the sputtering apparatus, the configuration was composed of three sputter chambers, two heating chambers, one cooling chamber, and one chamber for input and export.

Here, the configuration of the chamber is not limited thereto, and for example, the chamber may be configured of only a sputter chamber.

In the case of the transparent substrate, the film may be formed after heat treatment at a predetermined temperature (50 to 300 ° C.) to remove surface moisture and to improve the growth of the metal film. The film may be formed to improve surface roughness and to relieve stress after forming the metal film. Heat treatment at temperature (100 ~ 400 ℃).

2 is a schematic cross-sectional view showing an embodiment of a method for manufacturing a binary blank mask according to the present invention.

First, a light shielding film is formed by reactive sputtering using argon (Ar), nitrogen (N ₂ ), and methane (CH ₄ ) gas, targeting chromium (Cr) on a 6-inch transparent substrate 2 made of quartz. (4) chromium nitride (CrCN) is formed.

The composition of the chromium carbide nitride (CrCN) film as the light shielding film 4 is 0 to 20 at% of carbon (C), 0 to 60 at% of nitrogen (N), and the rest is made of chromium (Cr).

The light shielding film 4 contains ₅ to 100 sccm: 10 to argon (Ar): nitrogen (N ₂ ): methane (CH ₄ ), which is a mixing ratio of a reactive gas under conditions in which the vacuum degree of the vacuum chamber is 2 mTorr and the applied power is 1 kW. 95 sccm: It is formed in the state set to 0-10 sccm, and it forms into a film whose thickness is 200-800 mm.

Subsequently, reactive sputtering using argon (Ar), nitrogen (N ₂ ), and carbon dioxide (CO ₂ ) gas is performed on the light shielding film 4 by using chromium (Cr) as a target. (CrCON) is formed to a thickness of 50 to 400 kPa.

The antireflection film 6 may be formed by forming two or more layers or continuously changing the component content.

The composition of the chromium oxynitride (CrCON) film as the antireflection film 6 is 0 to 20 at% of carbon (C), 0 to 60 at% of oxygen (O), and 0 to 60 at% of nitrogen (N), and the rest is chromium (Cr). )

After forming a resist film 8 having a thickness of 3,000 kPa on the anti-reflection film 6 by using a spin coating method, a soft blank is performed on a hot plate to manufacture a binary blank mask according to the present invention.

In the above, soft baking is performed by setting temperature to 200 degreeC, and setting time to about 15 minutes.

In the above, a preferred embodiment of the method for manufacturing a binary blank mask according to the present invention has been described. However, the present invention is not limited thereto, and various modifications are made within the scope of the claims and the detailed description of the invention and the accompanying drawings. It is possible to do this and this also belongs to the scope of the present invention.

Compared with the conventional in-line method, the present invention by the cluster method can minimize the generation of fine particles due to the reproducibility of the membrane and the minimum transport system, thereby improving the product quality.

In addition, since selective film formation and heat treatment are possible, stress relaxation during vacuum deposition and surface residual ammonia concentration control are easy, and thus the adhesion of the photoresist on the antireflection film can be improved.

Claims (7)

       Forming a light shielding film or an antireflection film or a light shielding film and an antireflection film on a transparent substrate by using a cluster type reactive sputtering or vacuum deposition method for the purpose of improving the particles of the metal film; A method of manufacturing a blank mask, comprising applying a resist on the light blocking film or the anti-reflection film. The method of claim 1, The light shielding film and the antireflection film are formed using a sputtering method or a vacuum deposition method in a vacuum chamber in which an inert gas and an active gas are introduced using a metal as a matrix. Cobalt (Co), tantalum (Ta), tungsten (W), molybdenum (Mo), chromium (Cr), vanadium (V), palladium (Pd), titanium (Ti), niobium (Nb), Zinc (Zn), Hafnium (Hf), Germanium (Ge), Aluminum (Al), Platinum (Pt), Manganese (Mn), Iron (Fe), Silicon (Si), Nickel (Ni), Cadmium (Cd), At least one selected from the group consisting of zirconium (Zr), magnesium (Mg), lithium (Li), selenium (Se), copper (Cu), yttrium (Y), sulfur (S), As the inert gas, at least one or more selected from the group consisting of argon (Ar), helium (He), neon (Ne), and xeon (Xe) is used, The active gas is oxygen (O ₂ ), nitrogen (N ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrous oxide (N ₂ O), nitrogen oxides (NO), nitrogen dioxide (NO ₂ ), ammonia (NH ₃ ) A blank mask manufacturing method using at least one selected from methane (CH ₄ ), fluorine (F). The method of claim 2, The light blocking film or the anti-reflection film may be formed of chromium oxide (CrO), chromium nitride (CrN), chromium carbide (CrC), chromium carbide (CrCO), chromium nitride (CrCN), or chromium oxynitride when the metal matrix is chromium (Cr). (CrON), chromium carbide oxynitride (CrCON), chromium fluoride (CrF), chromium fluoride (CrNF), chromium fluoride (CrOF), chromium fluorocarbon (CrCF), chromium fluoronitride (CrCNF) A method for producing a blank mask, which is formed of a film containing at least one of chromium nitride (CrONF) and fluorocarbon oxynitride (CrCONF). The method according to claim 2 or 3, A method of manufacturing a blank mask, characterized in that the heat treatment at a predetermined temperature (50 ~ 400 ℃) before and after film formation for the purpose of removing moisture on the surface of the transparent substrate, improve adhesion of the metal film and improve resistance to chemicals. The method of claim 4, wherein The blank mask manufacturing method characterized in that the heat treatment at a temperature of 100 ~ 250 ℃. A method of manufacturing a blank mask and a photomask for manufacturing a semiconductor integrated circuit or a flat panel display selectively using the manufacturing method of any one of claims 1 to 5. It is manufactured by the blank mask manufacturing method in any one of Claims 1-5, The blank mask characterized by the above-mentioned.

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