KR20100098780A - Method of manufacturing stamp for nanoimprint - Google Patents

Abstract

The present invention relates to a method for manufacturing a nano imprint stamp having a moth eye pattern having a pitch or line width of 200 nm or less without using photolithography technology. Stamp manufacturing method for nanoimprint, forming a plurality of nanospheres arranged regularly on a substrate; A first etching step of reducing the size of the nanospheres, and a second etching step of etching the substrate using the nanospheres having a reduced size as an etch barrier, and continuously performing the first and second etchings, respectively, one at a time. A plurality of Morse Eye patterns are formed on the substrate by repeating the unit cycle a plurality of times. According to the present invention, a pitch or line width of 200 nm or less is free from pattern deformation occurring during exposure and development processes. There is an effect that can easily produce a stamp for having a nanoimprint.

Description

Manufacturing method of stamp for nanoimprint {METHOD OF MANUFACTURING STAMP FOR NANOIMPRINT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing technique of a semiconductor device, and more particularly, to a method for manufacturing a nano imprint stamp having a moth eye pattern.

Recently, semiconductor devices including optical members such as liquid crystal displays (LCDs), plasma display panels (PDPs), lenses, light emitting diodes (LEDs), and solar cells reduce optical energy loss due to surface reflection. As a method for improving light transmittance, a method of forming a moth eye pattern having periodic irregularities on the surface of the optical member has been proposed.

In general, when light passes through a predetermined material film, diffraction occurs and the straight component of the transmitted light is greatly reduced. However, when forming a moth eye pattern having periodic irregularities on the surface of the optical member, the shape of the moth eye pattern It is known that an antireflection effect and excellent transmission characteristics can be obtained for specific wavelength light corresponding to, height, pitch, line width, and the like. In particular, when the pitch or line width of the Morse eye pattern is 200 nm or less, it is possible to obtain an antireflection effect and excellent transmission characteristics against visible light.

Until now, a method of patterning an optical member using photolithography technology has been used to form a moth eye pattern on the surface of the optical member. However, due to the optical limitation of photolithography technology, it is very difficult to form a Morse Eye pattern with a pitch or line width of 200 nm or less, and form a Morse Eye pattern having a uniform shape on all substrates due to pattern deformation generated during exposure and development processes. There is a problem that is difficult to do. In addition, there is a problem in that a high cost and low productivity between processes. In addition, the photolithography technology has a problem in that it takes a lot of time and cost to form a mos-eye pattern on the entire surface of the large-area substrate.

Recently, in order to solve this problem, a method using nanoimprint lithography technology has been proposed. Nanoimprint lithography technology is known to have a superior effect on cost and productivity compared to conventional photolithography technology, especially on large area substrates.

However, in order to form the MOS eye pattern using the nanoimprint lithography technology, a stamp for the nanoimprint on which the MOS eye pattern is formed is required. At this time, since the stamp is formed by patterning the substrate for stamping using photolithography technology, it is still difficult to form a Morse eye pattern having a pitch or line width of 200 nm or less, and uniform in all stamps due to pattern deformation generated during exposure and development processes. There is a problem that it is difficult to form a Morse eye pattern having a shape.

The present invention has been proposed to solve the above problems of the prior art, and an object thereof is to provide a method for manufacturing a stamp for nanoimprint having a Morse eye pattern having a pitch or line width of 200nm or less.

Another object of the present invention is to provide a method for manufacturing a stamp for nanoimprint having a moth eye pattern without using photolithography technology.

According to an aspect of the present invention, there is provided a method for manufacturing a stamp for nanoimprint, comprising: forming a plurality of nanospheres regularly arranged on a substrate; A first etching step of reducing the diameter of the nanospheres and a second etching step of etching the substrate using the nanospheres having a reduced diameter as an etch barrier, and continuously performing the first and second etchings, respectively, one at a time. A plurality of Morse eye patterns are formed on the substrate by repeatedly performing a unit cycle. In this case, the unit cycle may be repeated until the nanosphere is completely removed.

According to another aspect of the present invention, there is provided a method for manufacturing a stamp for nanoimprint, comprising: regularly arranging a plurality of nanospheres on a substrate and etching the nanospheres to reduce the diameter of the nanospheres. And simultaneously etching the substrate with the nanospheres as an etch barrier to form a plurality of MOSFETs on the substrate. In this case, the forming of the moth eye pattern may be performed until the nanospheres are completely removed.

The present invention based on the above-described problem solving means, by using a nanosphere that can be regularly arranged through the coating step during the substrate etching process for forming a moth eye pattern as an etching barrier, without using a photolithography technology There is an effect that can easily form a Morse eye pattern having a pitch or line width of 200nm or less.

In addition, the present invention does not use the photolithography technology, it is possible to prevent the pattern deformation occurring during the exposure and development process, and has the effect of forming a moth eye pattern having a uniform shape on the entire substrate. .

In addition, the present invention controls the process conditions (for example, etching time, etching gas, etc.) and the number of repetitions of the unit cycle consisting of the first and second etching process parameters such as the sidewall slope, height, etc. of the Morse eye pattern There is an effect that can be easily adjusted.

In addition, the present invention by forming a moth eye pattern using a chemical dry etching method, there is an effect that can improve the productivity by simplifying the process.

DETAILED DESCRIPTION Hereinafter, the most preferred embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily implement the technical idea of the present invention. .

The present invention described below is optical energy loss due to surface reflection in a semiconductor device including an optical member, such as a liquid crystal display (LCD), a plasma display panel (PDP), a lens, a light emitting diode (LED), a solar cell And a moth eye pattern for forming a moth eye pattern having periodic irregularities on the surface of the optical member by using nanoimprint lithography technology as a method for reducing the light transmittance and improving light transmittance. Provided are a method for manufacturing a stamp for nanoimprint. In particular, the present invention provides a MOS eye having a pitch (or inter-pattern spacing) and line width of 200 nm or less in order to form a MOS eye pattern having excellent anti-reflection effect and transmission characteristics against visible light so as to be easily applied to a light emitting device and a display device. Provided is a method for manufacturing a stamp for nanoimprint having a pattern.

[First Embodiment]

1A to 1F are cross-sectional views illustrating a method for manufacturing a stamp for nanoimprint having a Morse Eye pattern according to a first embodiment of the present invention.

As shown in FIG. 1A, a plurality of nanospheres 12 are arranged on the substrate 11 in a regular manner. In this case, the adjacent nanospheres 12 are preferably formed to contact each other. Here, the nanospheres 12 means a spherical structure having a nano size.

The substrate 11 serves as a stamp for nanoimprint, and may use a silicon substrate. In addition, the substrate 11 may use various materials such as plastic, glass, quartz, and metal, and the like is not limited to any one material.

The nanospheres 12 serve as an etch barrier for the substrate 11 during an etching process for forming a moth eye pattern on the substrate 11, and may be formed of polystyrene balls. In addition, the nanospheres 12 may use various materials such as silica balls, glass balls, and the like, but are not limited to any one material.

In addition, the nanospheres 12 preferably have a diameter (or size) of 200 nm or less, for example, in the range of 10 nm to 200 nm, in order to form a Morse eye pattern having a pitch or line width of 200 nm or less. Here, since the nanospheres 12 serve as an etch barrier during the etching process of the substrate 11 for forming subsequent mos-eye patterns, when the diameter of the nanospheres 12 is less than 10 nm, due to insufficient etching margins. Forming a normal Morse eye pattern may not be easy.

The plurality of nanospheres 12 regularly arranged on the entire surface of the substrate 11 may apply a solution in which the plurality of nanospheres 12 are dispersed onto the substrate 11 so that the adjacent nanospheres 12 may contact all of the nanospheres 12. (12) After forming a single layer, it may be formed through a series of processes of removing the solution by vacuum or heat treatment. In this case, the solution in which the plurality of nanospheres 12 is dispersed may be formed by using a spin coating method, a slit coating method, a drop casting method, a dip casting method, or the like. It can be coated on (11).

As shown in FIG. 1B, the nanospheres 12 are partially etched to reduce the diameter of the nanospheres 12. Hereinafter, the reference numerals of the nanospheres 12 having reduced diameters are changed to '12A', and the etching process for reducing the diameters of the nanospheres 12 is referred to as 'first etching'.

The first etching may be performed using a plasma etch method, and an etching gas having an etching selectivity with respect to the substrate 11, that is, the nanospheres 12A may be well etched so that the substrate 11 is well etched. In this case, in order to uniformly reduce the diameter of the nanospheres 12A, the first etching may be performed using a plasma etching method, and the process conditions may be adjusted to have an isotropic etching characteristic. desirable. In addition, the diameter of the nanospheres 12A reduced during the first etching may be adjusted in consideration of the shape of the Morse eye pattern to be finally formed, for example, sidewall inclination and height.

For example, in the case where the substrate 11 is a silicon substrate and the nanospheres 12A are formed of polystyrene balls, the first etching does not apply bias power to the chamber but only source power. It can be carried out using a plasma generated by injecting a gas containing oxygen (O) or a mixed gas in which a gas containing oxygen and an inert gas are mixed in one state. At this time, the gas containing oxygen (O) acts as an etching gas of the nanospheres 12A and may use O ₂ gas, O ₃ gas, H ₂ O gas, N ₂ O gas and the like. The inert gas substantially participates in the etching of the nanospheres 12A and facilitates plasma generation, thereby serving to improve the etching efficiency. The source power serves to generate a plasma, and the bias power serves to accelerate particles in the plasma. Therefore, when the etching process is performed without applying bias power to the chamber and only source power is applied, isotropic etching characteristics can be secured.

As illustrated in FIG. 1C, the substrate 11 is etched using the nanospheres 12A having a reduced diameter as an etch barrier. Hereinafter, the process of etching the substrate 11 by using the nanospheres 12A as an etch barrier is abbreviated as 'second etching', and reference numerals of protrusions protruding onto the substrate 11 due to the second etching are referred to as '11A'. Mark it. At this time, the protrusion 11A finally acts as a Morse eye pattern.

The second etching may proceed in-situ in the same chamber as the first etching. Accordingly, the second etching may be performed using a plasma etching method, and the etching gas having an etching selectivity with respect to the nanospheres 12A as the etching gas, that is, the substrate 11 is well etched and the nanospheres 12A are well etched. It can be done using an etching gas that is not well etched. In this case, in order to form the sidewall S of the protrusion 11A to have a constant inclination, preferably a positive inclination, the second etching may be performed using a plasma etching method, and the process conditions may be adjusted to have anisotropic etching characteristics. It is preferable. Here, the protrusion 11A having a positive slope of the side wall may have a structure in which the line width of the protrusion 11A increases from the upper region to the lower region.

For example, when the nanospheres 12A are polystyrene balls and a silicon substrate is used as the substrate 11, the second etching is a gas containing fluorine (F) while the source power and the bias power are simultaneously applied to the chamber. Alternatively, the method may be performed using a plasma generated by injecting a mixed gas containing a mixture of fluorine-containing gas and inert gas. At this time, the gas containing fluorine acts as an etching gas of the substrate 11, carbon fluoride (C _x F _y , x, y is natural water except 0), methane fluoride gas (C _x H _y F _z , x, y , z is a natural number except 0). The inert gas serves as an etching gas for smoothly generating plasma and etching the substrate 11 to improve etching efficiency. The source power serves to generate a plasma, and the bias power serves to accelerate particles in the plasma. Therefore, when the etching process is performed while the bias power and the source power are simultaneously applied to the chamber, anisotropic etching characteristics can be secured.

The first etching and the second etching described above are performed once in succession, respectively, as a unit cycle. The first embodiment of the present invention is characterized by forming a moth eye pattern on the substrate 11 by repeating the above-described unit cycle a plurality of times.

As shown in FIG. 1D, the first etching is performed to partially reduce the diameter of the nanospheres 12A. Hereinafter, the reference numerals of the nanospheres 12A having a reduced diameter are referred to as '12B'. In this case, the first etching may be performed by the same method as described with reference to FIG. 1B.

As shown in FIG. 1E, the substrate 11 and the protrusion 11A are etched using the nanospheres 12B having the reduced diameter as an etch barrier by performing the second etching. Hereinafter, the reference numeral of the protrusion 11A whose shape is changed through the second etching is changed to '11B' and described. In this case, the second etching may be performed by the same method as described with reference to FIG. 1C.

As shown in FIG. 1F, the first etching process is performed until the nanospheres 12B are completely removed, and then the second etching process of etching the substrate 11 is performed to complete the MOS eye pattern 11C. That is, the MoSE pattern 11C is completed by repeating the unit cycle until the nanospheres 12B are completely removed. In this case, the first etching may be performed by the same method as the method described with reference to FIG. 1B, and the second etching may be performed by the same method as the method described with reference to FIG. 1C. At this time, the second etching is performed in a state in which the nanospheres 12B are completely removed, so that the upper portion of the Morse eye pattern 11C may have a horn shape.

In summary, the unit cycle of continuously performing the first etching for reducing the size of the nanospheres 12B and the second etching for etching the substrate 11 each with the reduced nanospheres 12B as an etch barrier are performed. The substrate 11 having the MOS eye pattern 11C, that is, the nanoimprint stamp having the MOS eye pattern can be completed by repeating a plurality of times until the nanospheres 12B are completely removed. In this case, the moth eye pattern 11C may have a conical shape in which the sidewalls S have a positive slope, and the bottom ends of adjacent moth eye patterns may contact each other and the spacing L between the peaks of the moth eye patterns may range from 10 nm to 200 nm. Can be.

As described above, the present invention uses photolithography technology by using nanospheres 12B as an etch barrier, which can be regularly arranged through a coating process during the etching process of the substrate 11 for forming the moth eye pattern 11C. It is possible to easily form the Morse-eye pattern 11C having a pitch or line width of 200 nm or less without using. In addition, since the photolithography technique is not used in the process of forming the moth eye pattern 11C, pattern deformation occurring during the exposure and development processes can be prevented at the source.

In addition, the present invention by adjusting the process conditions (eg, etching time, etching gas, etc.) of the first etching and the second etching and the number of repetitions of the unit cycle consisting of these, the inclination of the sidewall (S) of the MOS eye pattern (11C), Variables such as height can be easily adjusted.

On the other hand, after forming a predetermined material layer on the substrate 11, the material layer may be etched to form the MOS eye pattern 11C. However, when the MOS eye pattern 11C is formed by etching the material layer formed on the substrate 11, the MOS eye pattern 11C may be formed due to variables such as thermal expansion coefficient and adhesion between the substrate 11 and the material layer. The formed material layer may be peeled off from the substrate 11 or the material layer may be lost. Therefore, it is preferable to form the MOS eye pattern 11C by etching the substrate 11 so that the MOS eye pattern 11C and the substrate 11 are one body.

[Second Embodiment]

Hereinafter, in the second embodiment of the present invention to be described later, a moth-eye pattern having a pitch or line width of 200 nm or less is provided through one etching process without repeating a unit cycle consisting of the first etching and the second etching a plurality of times. It provides a method for producing a stamp for nanoimprint.

2A to 2B are cross-sectional views illustrating a method for manufacturing a stamp for nanoimprint having a Morse Eye pattern according to a second embodiment of the present invention.

As shown in FIG. 2A, a plurality of nanospheres 32 are formed on the substrate 31 which are arranged regularly. At this time, it is preferable to form adjacent nanospheres 32 in contact with each other. Here, the nanospheres 32 refers to a spherical structure having a nano size.

The substrate 31 serves as a stamp for nanoimprint, and may use a silicon substrate. In addition, the substrate 31 may use various materials such as plastic, glass, quartz, metal, and the like, and is not limited to any one material.

The nanospheres 32 serve as an etch barrier for the substrate 11 during an etching process for forming a moth eye pattern on the substrate 31, and may be formed of polystyrene balls. In addition, the nanospheres 32 may use various materials such as silica balls, glass balls, and the like, but are not limited to any one material.

In addition, the nanospheres 32 preferably have a diameter of 200 nm or less, for example, in the range of 10 nm to 200 nm, in order to form a Morse eye pattern having a pitch or line width of 200 nm or less. Here, since the nanospheres 32 serve as an etch barrier during the etching process of the substrate 31 for forming subsequent mos-eye patterns, when the diameter of the nanospheres 32 is less than 10 nm, there is a lack of etching margin. Forming a normal Morse eye pattern may not be easy.

The plurality of nanospheres 32 regularly arranged on the front surface of the substrate 31 may apply a solution in which the plurality of nanospheres 32 are dispersed on the substrate 31 so that the adjacent nanospheres 32 may contact all of the nanospheres 32. (32) After forming a single layer, it may be formed through a series of processes of removing the solution through vacuum or heat treatment. In this case, the solution in which the plurality of nanospheres 12 is dispersed may be formed by using a spin coating method, a slit coating method, a drop casting method, a dip casting method, or the like. It can coat on 31.

As shown in FIG. 2B, while reducing the diameter of the nanospheres 32, the substrate 31 is etched using the nanospheres 32 as an etch barrier to form a moth eye pattern 31A. At this time, the etching process is preferably proceeded to the point where the nanospheres 12 are completely removed.

An etching process for forming the Morse eye pattern 31A may be performed using a plasma etch method. In this case, in the second embodiment of the present invention, a chemical dry etching method (CDE) is used as the plasma etching method.

Here, the chemical dry etching means an etching method capable of simultaneously performing chemical etching and physical etching. Physical etching is a method of generating a plasma by using an inert gas (Ar, He, Xe, etc.) and injecting positive ions in the plasma vertically to the substrate to physically etch the etching target layer physically, Chemical etching is a method of generating a plasma by selecting a gas that is chemically well reacted in the etching layer and the plasma state, and purely chemically etching using activated neutral radicals in the plasma. Therefore, the chemical dry etching method in which the chemical etching and the physical etching are simultaneously performed uses the strong collision energy of ions by injecting cations in the plasma into the wafer, and at the same time, the etching rate is increased by using radicals that react well with the etching layer. It is a way to get synergy effect to increase order.

Hereinafter, when the substrate 31 is a silicon substrate and the nanospheres 32 are polystyrene balls, a method of forming the MOS eye pattern 31A using chemical dry etching will be described in detail.

The substrate 31 on which the nanospheres 32 are formed is loaded into the chamber of the plasma etching apparatus. Subsequently, while the source power and the bias power are simultaneously applied to the chamber, the diameter of the nanosphere 32 is reduced and the nanospheres 32 are reduced by using the plasma of the mixed gas in which the chemical etching gas and the physical etching gas are mixed into the chamber. The substrate 31 is etched using the etch barrier to form the MOS eye pattern 31A. At this time, the source power serves to generate a plasma, and the bias power serves to accelerate the ions in the plasma to enter the substrate 31.

The chemical etching gas may be a gas having an etching selectivity with respect to the substrate 31, that is, the substrate 31 may not be etched well and the nanospheres 32 may be well etched. Therefore, a gas containing oxygen, for example, an O ₂ gas, an O ₃ gas, an H ₂ O gas, an N ₂ O gas, or the like may be used as the chemical etching gas.

Inert gas may be used as the physical etching gas. At this time, the inert gas serves to etch the substrate 31 and at the same time to facilitate the plasma generation to improve the etching efficiency.

Here, the plasma etching apparatus for chemical dry etching may use an inductively coupled plasma (ICP), an electron cyclotron resonance (ECR), a microwave or a capacitively coupled plasma (CCP). In addition, the ratio of the etching gas, the source power, the bias power, the pressure, the top electrode, and the bottom electrode for the purpose of adjusting the inclination, the height, and the like of the sidewall S of the MOS eye pattern 31A. The temperature of the electroed can be adjusted.

The above-described chemical dry etching may be performed until the nanospheres 32 are completely removed, thereby completing a stamp having a plurality of Morse eye patterns 31A. At this time, the Morse eye pattern 31A may have a conical shape in which the sidewall S has a positive slope, and the bottom ends of adjacent Morse eye patterns 31A are in contact with each other, and the spacing L between the peaks of the Morse eye patterns 31A is different. It may have a range of 10nm ~ 200nm.

As described above, the present invention uses the photolithography technology by using the nanospheres 32, which can be regularly arranged through a coating process during the etching process of the substrate 31 for forming the Morse eye pattern 31A, as an etching barrier. It is possible to easily form the Morse eye pattern 31A having a pitch or line width of 200 nm or less without using the?. In addition, since the photolithography technique is not used in the process of forming the moth eye pattern 31A, pattern deformation occurring during the exposure and development processes can be prevented at the source.

In addition, by using the chemical dry etching method in the etching process for forming the MOS eye pattern 31A, it is possible to easily form the MOS eye pattern 31A through one etching process, and to simplify the process to improve productivity. Can be improved. In addition, by adjusting the process conditions during the etching process, it is possible to easily adjust variables such as the inclination, height, and the like of the sidewall S of the Morse eye pattern 31A.

Although the technical spirit of the present invention has been described in detail according to the above preferred embodiment, it should be noted that the above embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will appreciate that various embodiments within the scope of the technical idea of the present invention are possible.

1A to 1F are cross-sectional views illustrating a method for manufacturing a stamp for nanoimprint having a Morse Eye pattern according to a first embodiment of the present invention.

2A to 2B are cross-sectional views illustrating a method for manufacturing a stamp for nanoimprint having a Morse Eye pattern according to a second embodiment of the present invention.

* Description of symbols on the main parts of the drawings *

11, 31: substrate

12, 12A, 12B, 32: nanospheres

11A, 11B: protrusion

11C, 31A: Morse Eye Pattern

Claims (16)

Forming a plurality of nanospheres regularly arranged on the substrate; A first etching step of reducing the diameter of the nanospheres; And And etching the substrate using the nanospheres having a reduced diameter as an etch barrier, A method for manufacturing a stamp for a nanoimprint, wherein a plurality of moth eye patterns are formed on the substrate by repeatedly performing a plurality of unit cycles for continuously performing the first and second etchings, respectively. The method of claim 1, The unit cycle is a nanoimprint stamp manufacturing method is repeated until the nanospheres are completely removed. The method of claim 1, The Morse eye pattern is a nanoimprint stamp manufacturing method comprising a conical shape. The method of claim 3, The Morse eye pattern, A method for manufacturing a stamp for nanoimprinting, wherein the bottom ends of adjacent Morse Eye patterns are in contact with each other, and the spacing between peaks of the Morse Eye patterns is in a range of 10 nm to 200 nm. The method of claim 1, The first and second etching is nano-imprint stamp manufacturing method performed in-situ in the same chamber. The method of claim 1, The first etching and the second etching is performed using a plasma etching method, The first etching is performed by an isotropic etching, the second etching is an anisotropic etching method for producing a stamp for nanoimprint. The method of claim 6, The first etching is performed by applying only the source power in the state in which the bias power is not applied to the chamber, and the second etching is performed by applying the bias power and the source power to the chamber at the same time. The method of claim 1, The nanospheres comprise a polystyrene ball, the substrate comprises a silicon substrate stamp for nanoimprint. The method of claim 8, The first etching is performed using a gas containing oxygen (O), the second etching is performed using a gas containing fluorine (F) nano imprint stamp manufacturing method. Regularly arranging a plurality of nanospheres on a substrate; And Etching the nanospheres to reduce the diameter of the nanospheres and simultaneously etching the substrates using the nanospheres as an etch barrier to form a plurality of moth eye patterns on the substrates. Nanoimprint stamp manufacturing method comprising a. The method of claim 10, Forming the Morse eye pattern, Method for producing a stamp for nanoimprint to be carried out until the nanospheres are completely removed. The method of claim 10, The Morse eye pattern is a nanoimprint stamp manufacturing method comprising a conical shape. The method of claim 12, The Morse eye pattern, A method for manufacturing a stamp for nanoimprinting, wherein the bottom ends of adjacent Morse Eye patterns are in contact with each other, and the spacing between peaks of the Morse Eye patterns is in a range of 10 nm to 200 nm. The method of claim 10, Forming the Morse eye pattern, A method for producing a stamp for nanoimprinting, which is performed using a plasma etching method, but using a physical chemical etching method (CDE). The method of claim 10, The nanospheres comprise a polystyrene ball, the substrate comprises a silicon substrate stamp for nanoimprint. The method of claim 15, Forming the Morse eye pattern, A method for producing a stamp for nanoimprinting, using a mixed gas of a gas containing oxygen and an inert gas.

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