KR100780815B1 - Manufacturing method of blankmask and photomask for liquid crystal display - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blank mask, a photomask, and a manufacturing method for a liquid crystal display device for solving the problem of uniformity of resist residual amount. In the blank mask manufacturing method according to the present invention, a first layer including at least one selected from a light shielding film and a first antireflection film is formed on a transparent substrate, and then patterned by wet etching to form a first layer pattern. After forming a second layer including at least one selected from a second anti-reflection film and a semi-transmissive film on the transparent substrate including the first layer pattern, a resist is applied on the second layer. For the same wet etchant, the etch rate of the light shielding film is smaller than the etch rate of the semi-transmissive film, and the etch rate of the first anti-reflective film and the etching rate of the second anti-reflective film are between the etch rate of the light shielding film and the etch rate of the semi-transmissive film.

LCD, blank mask, photo mask, transmittance, retardation, transflective film, exposure, development, slit

Description

Manufacturing method of blank mask and photomask for liquid crystal display device

1 is a cross-sectional view schematically showing a general sputtering equipment.

2A to 2D are cross-sectional views illustrating an embodiment of a blank mask and a photomask manufacturing method according to the present invention.

3A and 3B are cross-sectional views of other blank and photomasks that may be prepared in accordance with the present invention.

4A and 4B are cross-sectional views of yet another blank and photomask that may be prepared in accordance with the present invention.

5A and 5B are cross-sectional views of yet another blank and photomask that can be made in accordance with the present invention.

6A and 6B are cross-sectional views of yet another blank and photomask that may be prepared in accordance with the present invention.

<Explanation of symbols for the main parts of the drawings>

10 ... transparent substrate 20 ... 1st layer

30 ... Light shielding film 40 ... First antireflection film

50 ... 2nd layer 60 ... 2nd anti-reflective film

70 Transflective film PR1, PR2 resist film

B1, B2, B3, B4, B5, B6 ... blank mask

P1, P2, P3, P4, P5, P6 ... photomask

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blank mask, a photomask, and a manufacturing method for a liquid crystal display (LCD), and to a blank mask, a photomask, and a method of manufacturing the same, which can use wet etching.

In the conventional liquid crystal display manufacturing process, a slit mask technique is used. The slit mask has a slit region in which a slit pattern is formed in addition to the light shielding region and the transmissive region, and the exposure light that passes through the slit region is diffracted by the slit pattern, thereby exhibiting a lower transmittance than when passing through the transmissive region. The light passing through the transmissive region is completely exposed to the resist corresponding portion on the substrate, whereas the light passing through the slit region is reduced to expose the resist corresponding portion on the substrate, resulting in incomplete exposure. As a result, a difference in solubility in the developing solution occurs during the development process, so that the resist of the completely exposed portion is removed, whereas the resist remaining film remains in the incompletely exposed portion. At this time, when the slit pattern becomes fine or the structure becomes complicated, it becomes difficult to control the control of the diffracted light passing through the slit region and the uniformity of the resist residual amount, resulting in cost loss in terms of production and yield.

In order to solve the above problems, a general phase shift mask may be used instead of a slit mask. At this time, the phase difference of the exposure light passing through the phase inversion film is designed to have a 180 degree and a specific transmittance at a specific wavelength, and a fine pattern is formed by using the interference phenomenon of the exposure light passing through the phase inversion film and the transparent substrate. However, in the exposure wavelength for the manufacturing process of the liquid crystal display device, there is a characteristic that it is difficult to control the resist residual amount and uniformity because of the characteristics of high transmittance and high phase difference.

As a method for improving this problem, it is possible to control the phase difference generation by controlling the thickness of the semi-permeable membrane and to adjust the residual amount of the resist by adjusting the transmittance, but it is difficult to apply the dry etching method in the photomask manufacturing process having a large area. . However, it is not possible to use wet etching in the current material system and much time is required for the selection of materials that are easy for wet etching and verification of production application.

It is an object of the present invention to provide a blank mask, a photomask, and a method of manufacturing the same to enable a large-area photomask process by applying a wet etching process when manufacturing a photomask to solve the problem of uniformity of resist residual amount. .

According to the present invention, a film forming a blank mask and a photomask such as a light shielding film, an antireflection film, and a semi-transmissive film is composed of a chromium (Cr) material, but has a different etching rate with respect to the same wet etchant, and thus is applicable to a large area. It is possible to solve the problems of the prior art by preparing a semi-permeable membrane that can easily control transmittance and retardation by using an easy wet etching method.

The blank mask manufacturing method according to the present invention comprises: forming a first layer including at least one selected from a light shielding film and a first antireflection film on a transparent substrate; Patterning the first layer by wet etching to form a first layer pattern partially exposing the surface of the transparent substrate; Forming a second layer including at least one selected from a second anti-reflection film and a semi-transmissive film on the transparent substrate including the first layer pattern; And applying a resist on the second layer, wherein, for the same wet etching solution, an etching rate of the light blocking film is less than an etching rate of the semi-transmissive film, and an etching rate and the second reflection of the first anti-reflection film The etching rate of the barrier layer is between the etching rate of the light blocking film and the etching rate of the transflective film.

The light shielding film, the first antireflection film, the second antireflection film, and the semi-transmissive film are preferably made of a material having the same metal as a matrix. For example, 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), Zirconium (Zr), Magnesium (Mg), Lithium (Li), Selenium (Se), Copper (Cu), Yttrium It can be formed of any one selected from the group consisting of (Y), sulfur (S), indium tin oxide (InSnO), and a combination thereof. In particular, chromium nitride (CrN), chromium oxide (CrO), chromium carbide (CrC), chromium carbide (CrCO), chromium nitride (CrCN), chromium oxynitride (CrON), chromium oxynitride (CrCON), chromium fluoride (CrF), chromium fluoride (CrNF), chromium fluoride (CrOF), chromium fluorocarbon (CrCF), chromium fluoronitride (CrCNF), chromium fluoride image quality (CrONF), and chromium fluoronitride (CrCONF) It is preferable to form with the chromium compound which is a component containing one or more of them.

The first layer may be formed regardless of the stacking order of the light blocking film and the first antireflection film, and the second layer may be formed regardless of the stacking order of the second antireflection film and the transflective film, and the light blocking film, the first antireflection film, The second anti-reflection film and the semi-transmissive film have semi-transmissive properties in which phase and transmittance can be adjusted in combination with each other. Each of the light blocking film, the first antireflection film, the second antireflection film, and the transflective film may be a single film or a structure having two or more layers.

The content of the light shielding film, the first antireflection film, the second antireflection film, and the semi-transmissive film is 0 to 95 at%, respectively, or a mixed content of carbon (C), oxygen (O), and nitrogen (N), and the rest is chromium (Cr It may be made of). The light shielding film, the first antireflection film, the second antireflection film, and the transflective film may be formed by using reactive sputtering or vacuum deposition (ALD, CVD, co-sputtering) by introducing an inert gas and a reactive gas into the vacuum chamber. As the inert gas, at least one selected from the group consisting of argon (Ar), helium (He), neon (Ne), and xenon (Xe) is used, and as the reactive gas, 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 ) and fluorine ( F) one or more selected from the group consisting of, the vacuum chamber of the vacuum degree is 1 to 5mTorr, the applied power is 0.5 to 2 kPa, the inert gas is argon, the reactive gas is nitrogen , Carbon dioxide and methane The mixing ratio can be 5 to 80%: 0 to 95%: 0 to 95%: 0 to 95% of argon: nitrogen: carbon dioxide: methane. Here, at least one of oxygen, nitrous oxide, nitrogen oxide and nitrogen dioxide may be used instead of the carbon dioxide, and the mixing ratio of the inert gas and the reactive gas is in the range of 1 to 95%: 0.1 to 100% of inert gas: reactive gas. Keep me.

The transflective film may have a transmittance of 5% to 70%, an optical phase shift of 0 ° to 100 °, and a thickness of 50 μs to 4,500 μs with respect to light having a wavelength of 190 nm to 500 nm as exposure light.

In order to improve the adhesion of the light shielding film, the first antireflection film, the second antireflection film, and the transflective film and the growth of the film in the blank mask manufacturing method, the transparent substrate is heated to a temperature of 50 ° C. to 700 ° C., and the stress relaxation and chemical The method may further include a heat treatment for 1 to 60 minutes in the range of 150 ° C to 700 ° C as a method for improving the resistance to.

Blank mask according to the present invention, a transparent substrate; A first layer pattern formed on the transparent substrate to partially expose the surface of the transparent substrate and including at least one selected from a light shielding film and a first anti-reflection film; A second layer formed on the transparent substrate including the first layer pattern and including at least one selected from a second anti-reflection film and a semi-transmissive film; And a resist film applied on the second layer, wherein, for the same wet etching solution, an etching rate of the light blocking film is less than an etching rate of the semi-transmissive film, and the etching rate of the first anti-reflection film and the second anti-reflection film The etching rate is between the etching rate of the light shielding film and the etching rate of the semi-transmissive film.

The photomask manufacturing method according to the present invention uses a blank mask according to the blankmask manufacturing method according to the present invention, and patterns the second layer of the blank mask by wet etching to form a second layer pattern partially exposing the surface of the transparent substrate. It is to include a step.

Specifically, the photomask manufacturing method according to the present invention comprises the steps of forming a light shielding film on a transparent substrate as a single film or two or more continuous film; Forming a first anti-reflection film as a single film or a continuous film of two or more layers on the light shielding film; Patterning the first anti-reflection film and the light shielding film by wet etching to form a first layer pattern partially exposing the surface of the transparent substrate; Forming a second anti-reflection film as a single film or two or more continuous films on the transparent substrate including the first layer pattern; Forming a transflective film as a single film or a continuous film of two or more layers on the second anti-reflection film; And patterning the second anti-reflection film and the semi-transmissive film by wet etching to form a second layer pattern exposing a part of the surface of the transparent substrate. For the same wet etchant, the etch rate of the light shielding film is The etching rate of the first anti-reflection film and the etching rate of the second anti-reflection film are smaller than the etching rate of the transflective film, and are between the etching rate of the light blocking film and the etching rate of the semi-transmissive film.

In addition, the photomask according to the present invention is that the second layer is patterned in the blank mask according to the present invention, a transparent substrate; A first layer pattern formed on the transparent substrate to partially expose the surface of the transparent substrate and including at least one selected from a light shielding film and a first anti-reflection film; And a second layer pattern formed on the transparent substrate including the first layer pattern and partially exposing the surface of the transparent substrate, the second layer pattern including at least one selected from a second anti-reflection film and a semi-transmissive film. The etching rate of the light blocking layer is smaller than the etching rate of the semi-transmissive layer, and the etching rate of the first anti-reflection film and the etching rate of the second anti-reflection film are between the etching rate of the light blocking film and the etching rate of the semi-transmissive film. It is

In the method of manufacturing a blank mask and a photo mask according to the present invention, a transparent substrate refers to a blank mask substrate for a flat panel display and a blank mask for a semiconductor composed of glass or quartz, and a flat panel display refers to a liquid crystal display device and an OLED. , Plasma display (PDP), electroluminescent display (FED), and the like.

In the blank mask and photomask manufacturing method according to the present invention, photolithography or electron beam ((E-beam) lithography is used for patterning a semi-transmissive film, a reflective ice film and a light shielding film (exposure with a single color laser or electron beam and development). The resist film as a component of the blank mask may be optical photoresist THMR-iP3500, THMR-iP3600, DPR-i7000, AZ-1500 or GXR, electron beam resist EBR-9, PBS or ZEP-7000, It can be selected and used among alkali-soluble resins such as FEP-171, a positive chemically amplified resist, FEN-270 or NEB-22, a resist composed of a component composed of PAG (Photo Acid Generator), and the like. The film is formed by spin coating or capillary coating, and the resist film is preferably composed of a film whose thickness can be adjusted from 1,000 mm to 15,000 mm. Further, by applying a resist film, and then, using a hot plate to be subjected to a soft bake (soft bake).

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. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. In the drawings illustrating embodiments of the present invention, like reference numerals in the drawings refer to like elements, and overlapping descriptions will be omitted.

FIG. 1 schematically illustrates a thin film deposition in a vacuum chamber of a general sputtering apparatus, and FIGS. 2A to 2D are cross-sectional views schematically illustrating a blank mask and a photomask manufacturing method according to a first embodiment of the present invention. admit.

Referring to FIG. 1, a thin film is formed on the surface of the transparent substrate 304 by installing a target 302 for thin film deposition under the vacuum chamber 300 and by installing a transparent substrate 304 thereon. Referring to a typical thin film formation process by sputtering, first, the transparent substrate 304 is mounted on the substrate holder 306, the target 302 is mounted on the target holder 308, and then the vacuum chamber is used by using the exhaust unit 400. A vacuum is formed in and maintained at 300. Thereafter, a gas is injected into the gas injection unit 402 to perform sputtering from the target 302, and it is deposited on the transparent substrate 304.

In the blank mask and the photomask manufacturing method according to the present invention, at least one of the light shielding film and the first antireflection film, and at least one of the second antireflection film and the transflective film is formed on the transparent substrate. It is preferable to form by using reactive sputtering or vacuum deposition (ALD, CVD, co-sputtering) by introducing an inert gas and a reactive gas in the same vacuum chamber 300.

In this case, at least one selected from the group consisting of argon (Ar), helium (He), neon (Ne) and xenon (Xe) is used as the inert gas, and oxygen (O ₂ ) and nitrogen (N) are used as the reactive gas. ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrous oxide (N ₂ O), nitric oxide (NO), nitrogen dioxide (NO ₂ ), ammonia (NH ₃ ), methane (CH ₄ ) and fluorine (F) It can be used by selecting one or more from the group consisting of. When the vacuum degree of the vacuum chamber 30 is 1 to 5 mTorr and the applied power is 0.5 to 2 kW, argon is used as the inert gas and nitrogen, carbon dioxide and methane are used as the reactive gases. Nitrogen: carbon dioxide: methane can be 5 to 80%: 0 to 95%: 0 to 95%: 0 to 95%. At this time, at least one of oxygen, nitrous oxide, nitrogen oxide and nitrogen dioxide may be used instead of carbon dioxide, and the mixing ratio of the inert gas and the reactive gas is in the range of 1 to 95%: 0.1 to 100% of inert gas: reactive gas. Keep it.

Next, referring to FIGS. 2A to 2D, a blank mask and a photomask manufacturing method according to a first embodiment of the present invention will be described.

Referring to FIG. 2A, after forming the first layer 20 on the transparent substrate 10 such as glass or quartz, the resist film PR1 is formed on the first layer 20. Here, the first layer 20 is formed by sequentially stacking the light shielding film 30 and the first antireflection film 40. In some cases, the first layer 20 may be formed of only the light shielding film 30 or only the first antireflection film 40. In some embodiments, the light shielding film 30 and the first anti-reflection film 40 may be stacked in different order. That is, the first layer 20 may be formed regardless of the stacking order of the light blocking film 30 and the first anti-reflection film 40. Each of the light blocking film 30 and the first anti-reflection film 40 may have a single film or a continuous film structure of two or more layers.

First, the light shielding film 30 may be formed of, for example, Co, Ta, W, Mo, Cr, V, Pd, Ti, Nb, Zn, Hf, Ge, Al, Pt, Mn, Fe, Si, Ni, Cd, Zr, It may be formed of any one selected from the group consisting of Mg, Li, Se, Cu, Y, S, InSnO and a combination thereof. In particular, it is preferable to form a chromium compound, and possible chromium compounds include components containing at least one of CrN, CrO, CrC, CrCO, CrCN, CrON, CrCON, CrF, CrNF, CrOF, CrCF, CrCNF, CrONF, and CrCONF. I have it. The component content is 0 to 95 at%, respectively, or a mixed content of carbon, oxygen, and nitrogen, and the remainder may be made of chromium.

Preferably, the light shielding film 30 forms chromium carbide (CrC) by reactive sputtering using argon and methane gas, targeting chromium. Among the various films formed on the transparent substrate 10, the etch rate is formed to be the smallest, so that the chromium carbide film, which is the light shielding film 30, is made from 0 to 95 at% of carbon and the remainder is made of chromium so that the etching proceeds slowly. The light shielding film 30 uses argon as an inert gas, methane as a reactive gas, and a mixing ratio of argon to methane under a condition of a vacuum chamber (300 in FIG. 1) having a vacuum degree of 2 mTorr and an applied power of 1 kW. 80%: Formed in a state of 0 to 30%, the thickness is formed to about 500 to 1000Å.

Then, in order to improve the adhesion and growth of the light-shielding film 30, the transparent substrate 10 is heated to a temperature of 50 ℃ to 700 ℃, a method for improving stress relaxation and resistance to chemicals 150 ℃ to 700 It may further comprise the step of heat treatment for 1 to 60 minutes in the range.

In the present embodiment, the first anti-reflection film 40 formed on the light shielding film 30 is also, for example, 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, S, InSnO and any combination thereof may be formed, and in particular, the same metal as the light shielding film 30 It is preferable to form with a substance which is a matrix, ie, a chromium compound. Possible chromium compounds are those having components comprising at least one of CrN, CrO, CrC, CrCO, CrCN, CrON, CrCON, CrF, CrNF, CrOF, CrCF, CrCNF, CrONF, and CrCONF. The component content is 0 to 95 at%, respectively, or a mixed content of carbon, oxygen, and nitrogen, and the remainder may be made of chromium.

Preferably, the first antireflection film 40 is formed of a chromium oxynitride carbide (CrCON) film, the composition of which is 0 to 20 at% carbon, 0 to 60 at% oxygen, 0 to 60 at% nitrogen, The remainder is made of chromium, in order to make the etching rate larger than that of the light shielding film 30 for the same wet etching solution.

The first anti-reflection film 40 uses argon as an inert gas and nitrogen and carbon dioxide as a reactive gas under a condition that the vacuum degree of the vacuum chamber (300 in FIG. 1) is 2 mTorr and the applied power is 1 kW. Nitrogen: Carbon dioxide is formed in a state of 5 to 80%: 20 to 95%: 0 to 30%, and the thickness is formed to about 100 to 300 kPa.

In order to improve the adhesion and growth of the first anti-reflection film 40, the transparent substrate 10 is heat treated at a temperature of 50 ° C to 700 ° C, and is 150 ° C to 700 as a method for improving stress relaxation and chemical resistance. It may further comprise the step of heat treatment for 1 to 60 minutes in the range.

On the first anti-reflection film 40, for example, AZ-1500 is applied to a thickness of 7000 Å using a spin coating method to form a resist film PR1. Then, soft bake is performed for about 15 minutes on a hot plate of about 200 ° C. In this way, the blank mask B1 for the liquid crystal display device is manufactured.

Next, a method of performing a photomask process with the primary blank mask B1 as shown in FIG. 2A is shown in FIG. 2B.

The resist film PR1 is exposed by a description method using an electron beam or a laser of monochromatic light, and a development process is performed on the exposed portion to form a resist pattern (not shown). Using the formed resist pattern as a mask, a wet etching solution, for example, Cr-7S solution, was used to sequentially wet the first layer 20, here, the first antireflection film 40 and the light blocking film 30, for about 170 seconds. The first layer pattern 20a exposing a part of the surface of the transparent substrate 10 is formed.

The remaining resist pattern is completely removed in a sulfuric acid solution by dipping, and then a cleaning process is performed to remove foreign substances that may remain on the surface of the first anti-reflection film 40.

By this process, the primary photomask P1 as shown in FIG. 2B is manufactured, which is transported for the secondary manufacturing process, and the cleaning process is performed again in consideration of contamination of foreign matters during transportation.

Next, referring to FIG. 2C, a second layer 50 is formed on the primary photomask P1 as shown in FIG. 2B, and a new resist film PR2 is formed on the second layer 50. Here, the second layer 50 is formed by sequentially stacking the second anti-reflection film 60 and the semi-transmissive film 70 to protect the first anti-reflection film 40, in some cases the second anti-reflection film It may be formed of only the 60, or may be formed of only the semi-transmissive film 70, or may be formed by changing the stacking order of the second anti-reflection film 60 and the semi-transmissive film 70. That is, the second layer 50 can be formed regardless of the stacking order of the second anti-reflection film 60 and the semi-transmissive film 70. Each of the second anti-reflection film 60 and the semi-transmissive film 70 may have a single film or a continuous film structure of two or more layers. In addition, the light shielding film 30, the first antireflection film 40, the second antireflection film 60, and the transflective film 70 have a semi-transmissivity capable of controlling phase and transmittance in combination with each other.

Preferably, the second anti-reflection film 60 is formed of a chromium oxynitride carbide (CrCON) film, the composition of which is 0 to 20 at% carbon, 0 to 60 at% oxygen, 0 to 60 at% nitrogen, The remainder is made of chromium, and is formed to have the same etching rate as that of the first anti-reflection film 40 with respect to the same wet etching solution.

The process of forming the second anti-reflection film 60 is the same as the process of forming the first anti-reflection film 40. That is, argon is used as the inert gas, nitrogen and carbon dioxide are used as the inert gas under the condition that the vacuum degree of the vacuum chamber (300 in FIG. 1) is 2 mTorr and the applied power is 1 kW, and the mixing ratio is 5 to 5 argon: nitrogen: carbon dioxide. 80%: 20 to 95%: 0 to 30% formed in a state, the thickness is formed to about 100 to 300Å.

Then, in order to improve the adhesion and growth of the second anti-reflection film 60, the transparent substrate 10 is heated to a temperature of 50 ℃ to 700 ℃, and a method for improving the stress relaxation and chemical resistance 150 It may further comprise the step of heat treatment for 1 to 60 minutes in the range of ℃ to 700 ℃.

The semi-transmissive film 70 is, for example, 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, S, InSnO, and any combination thereof. The light shielding film 30, the first antireflection film 40, and the second antireflection film 60 may be formed. It is preferable to form the same metal as) as a parent material, that is, a chromium compound. Possible chromium compounds are those having components comprising at least one of CrN, CrO, CrC, CrCO, CrCN, CrON, CrCON, CrF, CrNF, CrOF, CrCF, CrCNF, CrONF, and CrCONF. The component content is 0 to 95 at%, respectively, or a mixed content of carbon, oxygen, and nitrogen, and the remainder may be made of chromium.

Preferably, the semi-permeable membrane 70 is formed of chromium nitride (CrN), the composition of the film is 0 to 90 at% of nitrogen, the remainder is made of chromium, for the same wet etching solution, the light shielding film 30, The etching speed is higher than that of the first antireflection film 40 and the second antireflection film 60 so that the etching may proceed faster.

The semi-permeable membrane 70 uses argon as an inert gas and nitrogen as a reactive gas under a condition in which the vacuum degree of the vacuum chamber (300 in FIG. 1) is 2 mTorr and the applied power is 1 kW, and the ratio is argon: nitrogen. 5 to 80%: 20 to 95% in a state of forming a thickness of about 100 ~ 350 ~. At this time, the role of the transflective film 70 is formed in consideration of the transmittance and the phase difference between the second anti-reflection film 60 and the transflective film 70. The semi-transmissive film 70 may have a transmittance of 5% to 70% with respect to light having a wavelength of 190 nm to 500 nm, an optical phase shift of 0 to 100 degrees, and a thickness of 50 to 4,500 Hz.

On the transflective film 70, for example, AZ-1500 is applied to a thickness of 10000 kPa using a spin coating method to form a resist film PR2. Then, soft bake is performed for about 15 minutes on a hot plate of about 200 ° C. In this way, the final blank mask B2 for the liquid crystal display device is manufactured.

The blank mask (B2) prepared as described above is a transparent substrate 10; A first layer pattern 20a formed on the transparent substrate 10 to partially expose the surface of the transparent substrate 10 and including a light shielding film 30 and a first anti-reflection film 40; A second layer 50 formed on the transparent substrate 10 including the first layer pattern 20a and including a second anti-reflection film 60 and a semi-transmissive film 70; And a resist film PR2 applied on the second layer 50. For the same wet etchant, the etching rate of the light blocking film 30 is smaller than the etching rate of the transflective film 70, and the etching rate of the first antireflection film 40 and the etching rate of the second antireflection film 60 are light blocking films ( 30 is between the etching rate of the semi-permeable membrane 70 and the etching rate. As described above, the etching rate of the first anti-reflection film 40 and the etching rate of the second anti-reflection film 60 may be the same.

Next, a method of performing a photomask process with a blank mask B2 as shown in FIG. 2C is shown in FIG. 2D.

The resist film PR2 is exposed by a description method using an electron beam or a laser of monochromatic light, and a development process is performed on the exposed portion to form a resist pattern (not shown). Using the formed resist pattern as a mask, the second layer 50, the semi-transmissive layer 70, and the second anti-reflection layer 60 were sequentially wetted for about 25 seconds using a wet etching solution, for example, Cr-7S solution. By etching, a second layer pattern 50a exposing a part of the surface of the transparent substrate 10 is formed. The portion of the transparent substrate 10 where only the transflective film 70 and the second anti-reflective film 60 are placed is defined as the semi-transmissive film region H, so that the resist of the semi-transmissive film region during the exposure process of the liquid crystal display manufacturing process Since the residual amount of the resist during the developing process may be uniformly controlled due to incomplete exposure, the productivity and the process margin may be increased according to the manufacturing process.

As described above, in the present invention, the films are made of the same metal, for example, a chromium compound, but the etching rate of the transflective film 70 is the largest and the etching rate of the light shielding film 30 is the smallest. In the wet etching of 70, the light shielding film 30 and the like can be prevented from being etched. Therefore, since the light shielding film 30 and the semi-permeable film 70 can be patterned by using a wet etching method during the etching process, the process can be easily operated, and the cost through quality completion and process simplicity without investment of dry etching equipment. Reduction and high value-added products can be manufactured to increase competitiveness.

After the second layer pattern 50a is formed, the remaining resist pattern is completely removed by a dipping method in a sulfuric acid solution, and then a cleaning process is performed to remove foreign substances that may remain on the surface of the semi-permeable membrane 70. In this way, manufacture of the photomask P2 is completed.

The photomask P2 manufactured as described above may include a transparent substrate 10; A first layer pattern 20a formed on the transparent substrate 10 to partially expose the surface of the transparent substrate 10 and including a light shielding film 30 and a first anti-reflection film 40; And a second layer formed on the transparent substrate 10 including the first layer pattern 20a and partially exposing the surface of the transparent substrate 10, and including a second anti-reflection film 60 and a semi-transmissive film 70. The pattern 50a will be included. For the same wet etchant, the etching rate of the light blocking film 30 is smaller than the etching rate of the transflective film 70, and the etching rate of the first antireflection film 40 and the etching rate of the second antireflection film 60 are light blocking films ( 30 is between the etching rate of the semi-permeable membrane 70 and the etching rate.

As described above, according to the present invention, the blank mask manufacturing process and the photomask manufacturing process are performed discontinuously, and easy wet etching can be applied to the process in the large-area photomask process. It can be applied to the photomask manufacturing process without changing the blank mask material, thereby providing reliability and convenience for the blank mask.

Meanwhile, blank masks and photomasks for liquid crystal display devices having various thin film structures may be manufactured using the same blank mask and photomask manufacturing method as in the first embodiment.

First, FIG. 3A illustrates that only the light shielding film 30 is formed and patterned without forming the first antireflection film 40, and thereafter, the second antireflection film 60 (which is substantially the first antireflection film) and transflective thereon is formed. A cross-sectional view of the blank mask B3 in which the film 70 is sequentially formed and the resist film PR2 is applied, and FIG. 3B is used to pattern the second antireflective film 60 and the semi-transmissive film 70 to make it transparent. It is sectional drawing of the photomask P3 which exposed a part of surface of the board | substrate 10. FIG. It can be seen that the first anti-reflection film 40 is omitted as compared to the blank mask B2 of FIG. 2C and the photomask P2 of FIG. 2D.

Next, FIG. 4A shows that after forming and patterning only the light shielding film 30 without forming the first antireflection film 40, the transflective film 70 and the second antireflective film 60 are formed thereon. The anti-reflective film) is formed sequentially, and a cross-sectional view of the blank mask B4 to which the resist film PR2 is applied, and FIG. 4B is used to pattern the semi-transmissive film 70 and the second anti-reflective film 60 by using the same. FIG. 4 is a diagram of a photomask P4 exposing a part of the surface of the transparent substrate 10. It can be seen that the stacking order of the semi-transmissive film 70 and the second anti-reflection film 60 is changed to the blank mask B3 of FIG. 3A and the photomask P3 of FIG. 3B.

Subsequently, in FIG. 5A, after forming and patterning only the light shielding film 30 without forming the first antireflection film 40, the semi-transmissive film 70 is formed without forming the second antireflection film 60. Fig. 5B is a cross sectional view of a photomask P5 in which a part of the surface of the transparent substrate 10 is exposed by patterning the semi-transmissive film 70 using the resist film PR2 coated thereon. to be. It can be seen that the second anti-reflection film 60 is omitted as compared to the blank mask B4 of FIG. 4A and the photomask P4 of FIG. 4B.

Next, FIG. 6A illustrates a blank mask in which only the second anti-reflection film 60 is formed and the resist film PR2 is applied after forming and patterning only the light shielding film 30 without forming the first anti-reflection film 40. 6B is a cross-sectional view of the photomask P6 exposing a part of the surface of the transparent substrate 10 by patterning the second anti-reflection film 60 using the same. It can be seen that the semi-transmissive layer 70 is omitted as compared to the blank mask B3 of FIG. 3A and the photomask P3 of FIG. 3B.

As mentioned above, the present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications may be made by those skilled in the art within the technical spirit of the present invention. It is obvious.

As described above, the blank mask and the photomask manufacturing method for a liquid crystal display according to the present invention control the etching rate of the chromium material which is generally used in the process for manufacturing the transflective film of the photomask manufacturing process. In addition, the antireflection film may be formed of the same series material. It can be applied to the photomask manufacturing process without changing the blank mask material, thereby providing reliability and convenience for the blank mask.

The blank mask manufacturing process and the photomask manufacturing process are performed discontinuously, and easy wet etching can be applied to the process in the large-area photomask process.

Therefore, the process can be easily operated, and cost reduction and high value-added products can be manufactured through quality completion and process simplification without the investment of dry etching equipment, thereby increasing competitiveness.

In addition, since the resist of the semi-transmissive layer region is incompletely exposed during the exposure process of the liquid crystal display manufacturing process, the residual amount of the resist may be uniformly controlled during the development process, thereby increasing productivity and process flexibility according to the manufacturing process.

Claims (17)

Forming a first layer including at least one selected from a light shielding film and a first anti-reflection film on the transparent substrate; Patterning the first layer by wet etching to form a first layer pattern partially exposing the surface of the transparent substrate; Forming a second layer including at least one selected from a second anti-reflection film and a semi-transmissive film on the transparent substrate including the first layer pattern; And Applying a resist on the second layer; For the same wet etchant, the etch rate of the light blocking film is smaller than the etch rate of the semi-transmissive film, and the etch rate of the first anti-reflective film and the etch rate of the second anti-reflective film are etched from the light-shielding film and the etch rate of the semi-transmissive film. Method for producing a blank mask, characterized in that between speeds. The method of claim 1, wherein the light shielding film, the first antireflection film, the second antireflection film, and the semi-transmissive film are made of a material having the same metal as a matrix. The method of claim 2, wherein the light blocking film, the first antireflection film, the second antireflection film, and the transflective film are cobalt (Co), tantalum (Ta), tungsten (W), molybdenum (Mo), chromium (Cr), and 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), zirconium (Zr), magnesium (Mg), lithium (Li), selenium (Se), copper (Cu), yttrium (Y), sulfur (S) ), Indium tin oxide (InSnO) and a blank mask manufacturing method characterized in that it is formed by any one selected from the group consisting of these. The method of claim 1, wherein the light shielding film, the first antireflection film, the second antireflection film, and the transflective film are formed of a chromium (Cr) compound, and the chromium compound is chromium nitride (CrN), chromium oxide (CrO), or chromium carbide ( CrC), chromium carbide (CrCO), chromium nitride (CrCN), chromium oxynitride (CrON), chromium carbide oxynitride (CrCON), chromium fluoride (CrF), chromium fluoride (CrNF), chromium fluoride (CrOF) ), Chromium fluorocarbon (CrCF), chromium oxynitride (CrCNF), chromium oxynitride (CrONF), and chromium fluoronitride (CrCONF) is a component comprising a blank mask manufacturing method characterized in that . The light blocking film of claim 1, wherein the first layer is formed regardless of the stacking order of the light blocking film and the first antireflection film, and the second layer is formed regardless of the stacking order of the second antireflection film and the semi-transmissive film. The blank mask manufacturing method, characterized in that the first anti-reflection film, the second anti-reflection film and the semi-transmissive film has a semi-transmissive ability to control the phase and transmittance in combination with each other.  The method of claim 1, wherein each of the light blocking film, the first antireflection film, the second antireflection film, and the transflective film has a structure of two or more layers. The method of claim 1, wherein the component of the light shielding film, the first antireflection film, the second antireflection film and the semi-transmissive film is each of carbon (C), oxygen (O) and nitrogen (N) or a mixed content of 0 to 95 at% , The remainder is made of a blank mask, characterized in that made of chromium (Cr).  The method of claim 1, wherein the light shielding film, the first antireflection film, the second antireflection film, and the transflective film are formed using a reactive sputtering or vacuum deposition method in which an inert gas and a reactive gas are introduced into a vacuum chamber. Blank mask manufacturing method. The method of claim 8, wherein the inert gas is selected from one or more selected from the group consisting of argon (Ar), helium (He), neon (Ne), and xenon (Xe), and the reactive gas may be 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 ) And at least one selected from the group consisting of fluorine (F). According to claim 8, wherein the vacuum degree of the vacuum chamber is 1 to 5mTorr, the applied power is 0.5 to 2 kW, argon as the inert gas, nitrogen, carbon dioxide and methane as the reactive gas is mixed with each gas A ratio of argon: nitrogen: carbon dioxide: methane is 5 to 80%: 0 to 95%: 0 to 95%: 0 to 95%. The method of claim 10, wherein at least one of oxygen, nitrous oxide, nitrogen oxide, and nitrogen dioxide is used in place of the carbon dioxide, and a mixing ratio of the inert gas and the reactive gas is 1 to 95%: 0.1 to 0.1% of the inert gas. Blank mask manufacturing method, characterized in that maintained within 100% range. The blank of claim 1, wherein the transflective film has a transmittance of 5% to 70%, a light phase shift of 0 ° to 100 °, and a thickness of 50 ° to 4,500 ° with respect to light having a wavelength of 190 nm to 500 nm. Mask manufacturing method. The method of claim 1, wherein the transparent substrate is heat-treated at a temperature of 50 ℃ to 700 ℃ in order to improve the adhesion of the light-shielding film, the first anti-reflection film, the second anti-reflection film and the semi-transmissive film and the growth of the film, the stress relaxation and chemical Method for improving the resistance to the blank mask manufacturing method characterized in that it further comprises the step of heat treatment for 1 to 60 minutes in the range of 150 ℃ to 700 ℃. Transparent substrate; A first layer pattern formed on the transparent substrate to partially expose the surface of the transparent substrate and including at least one selected from a light shielding film and a first anti-reflection film; A second layer formed on the transparent substrate including the first layer pattern and including at least one selected from a second anti-reflection film and a semi-transmissive film; And It includes a resist film applied on the second layer, For the same wet etchant, the etch rate of the light blocking film is smaller than the etch rate of the semi-transmissive film, and the etch rate of the first anti-reflective film and the etch rate of the second anti-reflective film are etched from the light-shielding film and the etch rate of the semi-transmissive film. Blank mask, characterized in that between speeds. The second layer pattern which partially exposes the surface of the transparent substrate by using a blank mask according to the blank mask manufacturing method according to any one of claims 1 to 13, and patterning the second layer of the blank mask by wet etching. Photomask manufacturing method comprising the step of forming a. Forming a light shielding film as a single film or a continuous film of two or more layers on the transparent substrate; Forming a first anti-reflection film as a single film or a continuous film of two or more layers on the light shielding film; Patterning the first anti-reflection film and the light shielding film by wet etching to form a first layer pattern partially exposing the surface of the transparent substrate; Forming a second anti-reflection film as a single film or two or more continuous films on the transparent substrate including the first layer pattern; Forming a transflective film as a single film or a continuous film of two or more layers on the second anti-reflection film; And Patterning the second anti-reflection film and the semi-transmissive film by wet etching to form a second layer pattern partially exposing the surface of the transparent substrate; For the same wet etchant, the etch rate of the light blocking film is smaller than the etch rate of the semi-transmissive film, and the etch rate of the first anti-reflective film and the etch rate of the second anti-reflective film are etched from the light-shielding film and the etch rate of the semi-transmissive film. A method of manufacturing a photomask, characterized in that between speeds. Transparent substrate; A first layer pattern formed on the transparent substrate to partially expose the surface of the transparent substrate and including at least one selected from a light shielding film and a first anti-reflection film; And A second layer pattern formed on the transparent substrate including the first layer pattern and partially exposing the surface of the transparent substrate, the second layer pattern including at least one selected from a second anti-reflection film and a semi-transmissive film, For the same wet etchant, the etch rate of the light blocking film is smaller than the etch rate of the semi-transmissive film, and the etch rate of the first anti-reflective film and the etch rate of the second anti-reflective film are etched from the light-shielding film and the etch rate of the semi-transmissive film. A photomask, characterized in that between speeds.

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