KR101512158B1 - Master for imprint and manufacturing method thereof - Google Patents

Abstract

A master for imprinting which forms a concave-convex pattern by mechanical processing and a method for producing the same. A method of manufacturing a master for imprinting includes: preparing a substrate of a brittle material; forming a first concavo-convex pattern by scratching the surface of the substrate with a tool to increase a processing depth, Fitting the measured load to one of the machining depth and the machining length and determining a limit load of the tool from the fitting data; and applying a load value lower than the limit load to the tool, And scratching the surface of the second concavo-convex pattern with a tool to form a second concavo-convex pattern.

Description

[0001] MASTER FOR IMPRINT AND MANUFACTURING METHOD THEREOF [0002]

The present invention relates to a master for imprinting, and more particularly, to a master for imprinting which forms a concave-convex pattern by mechanical working and a method of manufacturing the same.

The nanoimprint technique proposed for ultra-fine processing is attracting attention as an efficient and economical pattern forming technique. The nanoimprint technique uses a mold (or stamper) for imprinting in which a nano-sized irregular pattern is formed on the surface.

In a typical nanoimprinting process, a resin is coated on a substrate to be processed, a mold for imprinting is laminated on the substrate so that the concavo-convex pattern is in contact with the resin, the resin is deformed by pressing, and the resin is cured by heat or ultraviolet rays ≪ / RTI > By using this nanoimprint technology, complicated stepped patterns can be easily formed in one step on a substrate to be processed.

The imprint mold is manufactured by a method of replicating a master for imprint. A conventional method of manufacturing a master for imprinting includes a step of forming a mask layer on a substrate and exposing a part of the substrate by patterning the mask layer by a method such as electron beam or interference lithography and etching the exposed substrate surface .

However, the imprinting master thus produced mainly forms a continuous pattern of a rectangular cross section or a discontinuous pattern such as a cylinder or a quadrangular column, and the pattern shape that can be embodied is very limited. In addition, since the electron beam or interference lithography technique is very difficult to apply to a large-area flat plate or a cylindrical mold (roll mold), it is also technically difficult to manufacture a large-area master that can secure economical efficiency.

It is an object of the present invention to provide a master for imprinting and a method for manufacturing the same that can form concave-convex patterns of various shapes by a simpler method without using electron beam or interference lithography and etching process.

The present invention also provides a master for imprinting which can be manufactured in a large-area flat plate or a cylindrical shape, and a method of manufacturing the same.

A method of manufacturing a master for imprinting according to an embodiment of the present invention includes the steps of preparing a substrate of a brittle material, forming a first concavo-convex pattern by scratching the surface of the substrate with a tool, Measuring a depth, a machining length and a load of the tool in real time, fitting the measured load to one of the machining depth and machining length, determining a limit load of the tool from the fitting data, And applying a lower load value and then scratching the surface of the substrate with a tool to form a second concave-convex pattern.

The tool can be a diamond tool. The depth and width of the first irregular pattern can be formed on a nanometer scale or a micrometer scale.

When measuring the load of the tool, the horizontal load and the vertical load of the tool can be measured using the sensor installed in the machining unit. When forming the first concavo-convex pattern, the soft machining section and the brittle machining section may appear in order along the machining length.

The fitting may be applied to a case where a horizontal load is fitted to the machining length, a horizontal load is fitted to the machining depth, a vertical load is fitted to the machining length, and a case where the vertical load is fitted to the machining depth .

In the fitting data, there are several points at which the load changes abruptly, and the limit load of the tool can be determined by the load at the point having the smallest load among the points where the load suddenly changes.

The depth of the second irregular pattern may be formed on the nanometer scale, and the width of the second irregular pattern may be formed on the nanometer scale or the micrometer scale. The substrate may be formed of either a flat plate or a cylindrical shape. The substrate may include any one selected from the group consisting of silicon, glass, sapphire, and germanium.

The imprinting master according to an embodiment of the present invention is made of a brittle material and forms a concavo-convex pattern formed by mechanical scratching.

The brittle material may include any one selected from the group consisting of silicon, glass, sapphire, and germanium. The depth of the concavo-convex pattern can be formed on the nanometer scale, and the cross-sectional shape of the concavo-convex pattern can correspond to the cross-sectional shape of the tool tip used in the scratch processing. The master for imprinting may be formed in a flat or cylindrical shape.

According to the present embodiment, it is possible to easily form a concavo-convex pattern of various cross-sectional shapes by using a simple mechanical scratching process without using an electron beam or an interference lithography technique and an etching process. In addition, it is possible to easily form a concavo-convex pattern on a large-area or cylindrical substrate, and the imprint master can be easily made into a large-sized or roll-formed mold, thereby improving the economical efficiency of the nanoimprint technique.

FIG. 1 is a process flow diagram illustrating a method of manufacturing a master for imprinting according to an embodiment of the present invention.
Fig. 2 is a schematic view showing the substrate of the second step shown in Fig. 1. Fig.
3 is a scanning electron microscope (SEM) photograph of a concave-convex pattern obtained by the scratch processing in the second step.
4 is a graph showing the result of fitting the load measured in the second step with respect to the processing length.
Fig. 5 is a schematic view showing the substrate of the fourth step shown in Fig. 1. Fig.
6 is an optical microscope photograph of a silicon wafer on which the scratch processing of the fourth step is completed.
Fig. 7 is a graph showing the result of measuring the cross-section of the concavo-convex pattern of Fig. 6 with an atomic force microscope (AFM).
8 is a schematic view showing a modified example of the substrate shown in Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

FIG. 1 is a process flow diagram illustrating a method of manufacturing a master for imprinting according to an embodiment of the present invention.

Referring to FIG. 1, a method of manufacturing a master for imprinting includes a first step (S10) of preparing a substrate of a brittle material, a step of scratching the surface of the substrate with a tool to form a first concavo-convex pattern, And a second step (20) of measuring the machining depth and the machining length and the load of the tool in real time while increasing the machining depth.

The manufacturing method of the imprinting master further includes a third step (S30) of fitting the measured load to one of the machining depth and the machining length and determining the limit load of the tool from the fitting data, And a fourth step (S40) of forming a second concave-convex pattern by scratching the surface of the substrate with a tool after applying a low load value.

In the first step S10, the substrate is made of a brittle material such as silicon, glass, sapphire, or germanium. For example, the substrate may be a silicon wafer. Since such a substrate is excellent in strength, a plurality of imprint molds (or stamps) can be reproduced without surface damage.

The first concavo-convex pattern is a test pattern for forming a second concavo-convex pattern, and the second concavo-convex pattern is a pattern of an imprint master for replicating an actual imprint mold. The first concavo-convex pattern can be formed in the clearance space at the edge of the substrate.

Fig. 2 is a schematic view showing the substrate of the second step shown in Fig. 1. Fig.

Referring to FIG. 2, in the second step S20, the surface of the substrate 100 is scratched by the tool 50. As shown in FIG. Scratching is a processing method for moving the tool 50 along one direction while pressing the substrate 100 with the tool 50. The first irregular pattern 110 is formed along the movement trajectory of the tool 50. [ The depth and width of the first concave-convex pattern 110 may be formed on a nanometer scale (1 nm or more and less than 1,000 nm) or a micrometer scale (1 μm or more and less than 1,000 μm).

The tool 50 used in the second step S20 consists of an ultra hard tool having a very sharp tip to form the first irregular pattern 110 of nanometer or micrometer size. For example, a diamond tool may be used. In the course of the scratching process, the tool 50 is subjected to a vertical load pressing the substrate 100 and a horizontal load for moving the determined locus.

In the second step S20, the first concavo-convex pattern 110 is formed by scratching, and at the same time, the machining depth and the machining length and the load (horizontal load and vertical load) of the tool 50 are measured in real time do. The load of the tool 50 can be measured by using a sensor provided on a machining apparatus (not shown) that supports the tool 50. Since the measurement of the load of the tool 50 using the sensor is well known, detailed description thereof will be omitted.

In Fig. 2, P1 represents a machining start point, and P2 represents a machining complete point. The tool moves from the point P1 to the point P2 to form the first concavo-convex pattern 110. As the moving distance (working length) increases, the load applied to the tool gradually increases, so that the depth and width of the first concavo- Increases gradually.

When the substrate 100 is scratch-processed while the load of the tool 50 is constantly increased, the soft machining sections P1 to P3 showing a clean machined cross section along the machining length and the soft machining sections P1 to P3 showing cracks, The outgoing brittle machining sections (P3 to P2) appear in order. In Fig. 2, P3 represents a transition point between the soft machining section and the brittle machining section, and reference numeral 115 represents a crack formed in the brittle machining section.

This result means that although the substrate 100 is a brittle material, it can be soft-worked like a metal at a certain processing depth.

In the method for manufacturing an imprinting master according to the present embodiment, the soft machining section of the brittle material is quantitatively measured and the limit load of the tool 50 is determined by using the measurement data, so that the second unevenness So that a pattern can be formed.

Fig. 3 is a scanning electron microscope (SEM) photograph of the first concavo-convex pattern obtained by the scratch processing in the second step, Fig. 4 is a photograph showing the results obtained by fitting the load (horizontal load) Fig.

Referring to FIGS. 3 and 4, in the third step S30, the load measured in the second step S20 is fitted to either the machining depth or the machining length. Since the load measured in the second step S20 includes the horizontal load and the vertical load, the horizontal load may be fitted to the processing length, the horizontal load may be fitted to the processing depth, the vertical load may be fitted to the processing length, The vertical load can be fitted to the machining depth.

According to the characteristics of the processing apparatus and the processing conditions, one of the four cases described above is selected for fitting. Fig. 4 shows the result of fitting the horizontal load to the machining length.

When the fitting data of FIG. 4 is analyzed, the horizontal load tends to be proportional thereto as the machining length increases. At this time, in the fitting data, it is observed that there are a plurality of points at which a load suddenly changes, that is, a so-called load splashing point. 4A, 4B, 4C, 4D and 4E show the points at which the load suddenly changes.

The abrupt change in the load means that the substrate 100 breaks during the scratching process. The points (a) to (e) shown in FIG. 3 correspond to the points (a) to (e) in FIG. 4 and it can be confirmed that the substrate is broken at each of the points (a) to (e) .

In the third step S30, a point at the foremost point among the plurality of points at which the load changes abruptly, that is, a point having the smallest load value (point (a) in FIGS. 3 and 4) is selected, Is determined as the limit load of the tool. In FIGS. 3 and 4, the point (a) represents the turning point at which the brittle machining section starts, and the limit load of the tool 50 means the load at the turning point at which the brittle machining section starts.

Fig. 5 is a schematic view showing the substrate of the fourth step shown in Fig. 1. Fig.

Referring to FIG. 5, in a fourth step S40, a load value lower than a limit load is applied to the tool 50, and then the surface of the substrate 100 is scratch-processed to form a second concavo-convex pattern 120. FIG. The second uneven pattern 120 is formed on the substrate 100 to complete the manufacturing of the imprinting master 200. [

As a load value lower than the limit load is applied to the tool 50, only the soft machining section exists in the second concavo-convex pattern 120. In other words, the second concavo-convex pattern 120 has a smooth machining shape without breaking the entire machining length. The depth of the second concavo-convex pattern 120 may belong to the nanometer scale, and the width of the second concavo-convex pattern 120 may belong to the nanometer scale or the micrometer scale.

In addition, since the cross section of the second concavo-convex pattern 120 corresponds to the cross-sectional shape of the tip of the tool 50, various patterns of concavo-convex patterns can be formed on the imprinting master 200. For example, when the tip of the tool 50 is formed into a triangular section, a second concavo-convex pattern 120 having a triangular section can be formed. Since the triangular pattern exerts the same optical effect as the prism, the nano imprint technique can be applied to the manufacture of various optical members by forming the triangular second concavo-convex pattern 120 on the imprinting master 200.

FIG. 6 is an optical microscope photograph of a silicon wafer on which the scratch processing of the fourth step is completed, and FIG. 7 is a graph showing a result of measurement of the cross-section of the concavo-convex pattern of FIG. 6 with an atomic force microscope (AFM).

Referring to FIG. 6, it can be seen that a concave-convex pattern having a very constant processing width was formed on the surface of the silicon wafer, and no part of the material was broken around the concavo-convex pattern. As described above, according to this embodiment, the imprinting master which is a brittle material can be smoothly machined as smooth as a general metal without breaking.

7, the cross-section of the concavo-convex pattern formed on the silicon wafer has a triangular shape corresponding to the cross-sectional shape of the tool tip. However, it is important that the inclined angle of the tool tip and the inclination angle of the cross section of the concave and convex pattern are different from each other, but it is important that the concave and convex pattern is machined to correspond to the cross section of the tool tip. It can be confirmed that the tool is machined into a shape corresponding to the cross section of the tool tip.

The mold for imprinting or stamp can be manufactured by replicating the imprinting master 200 described above. The resin on the substrate to be processed is cured by press-molding the resin on the substrate with an imprint mold or a stamp to transfer the concave-convex pattern of the imprint mold to the resin .

8 is a schematic view showing a modified example of the substrate shown in Fig.

Referring to FIG. 8, the substrate 100 is formed in a cylindrical shape, and a second uneven pattern 120 is formed on the substrate 100 using a tool 50 having a load value lower than a critical load. The tool 50 can be set in various ways such as moving along the axial direction of the substrate 100, moving along the circumferential direction, or moving along the oblique direction.

Further, irrespective of the shape of the substrate 100, the machining apparatus (not shown) may include a plurality of tools to simultaneously form a plurality of second concave-convex patterns 120. When the substrate 100 has a cylindrical shape, the processing apparatus may have a plurality of tools arranged along the circumferential direction of the substrate 100.

5 and 8 illustrate the second concavo-convex pattern 120 having a constant depth and a constant width. However, when the load of the tool 50 is changed within a range not exceeding the limit load, ) Can be changed. 5 and 8 show the second concave-convex pattern 120 in a straight line, the second concave-convex pattern 120 may be formed in various shapes such as a curved line or a lattice.

According to the manufacturing method of the imprinting master 200 described above, irregular patterns of various cross-sectional shapes can be easily formed using simple mechanical scratching without using electron beam or interference lithography technique and etching process.

Further, since the electron beam or the interference lithography technique is not used, the concavo-convex pattern can be easily formed on the large-area or cylindrical substrate. Therefore, the imprinting master can be easily faced or roll-molded, which can increase the economical efficiency of nanoimprint technology.

The imprinting master 200 manufactured by the above-described method includes a bumpy material such as silicon, glass, sapphire, and germanium, and includes a concave-convex pattern (second concave-convex pattern) 120 formed by mechanical scratching . At this time, the cross-sectional shape of the concavo-convex pattern 120 corresponds to the cross-sectional shape of the tip of the tool 50 used for the scratch processing, and can be processed into various planar shapes.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Of course.

100: substrate 110: first irregular pattern
120: second concave / convex pattern 50: tool
200: Master for imprint

Claims (13)

Preparing a substrate of brittle material;
A step of scratching a surface of the substrate with a tool to form a first concavo-convex pattern and simultaneously measuring the depth of machining, the machining length and the load of the tool while increasing the machining depth;
Fitting the measured load to either the machining depth and the machining length, and determining a limit load of the tool from the fitting data; And
Applying a load value lower than the limit load to the tool, and scratching the surface of the substrate with the tool to form a second concavo-convex pattern
Wherein the imprinting master is formed by a method comprising the steps of: The method according to claim 1,
The tool is a diamond tool,
Wherein the depth and width of the first concave-convex pattern are formed on a nanometer scale of 1 nm or more and less than 1,000 nm or a micrometer scale of 1 占 퐉 or more and less than 1,000. 3. The method of claim 2,
Wherein a horizontal load and a vertical load of the tool are measured using a sensor installed in the machining apparatus when measuring the load of the tool. 3. The method of claim 2,
Wherein a soft machining section and a brittle machining section appear in order along the machining length when forming the first concavo-convex pattern. The method of claim 3,
The fitting can be used for fitting a horizontal load to the machining length, fitting the horizontal load to the machining depth, fitting the vertical load to the machining length, and fitting the vertical load to the machining depth By weight of the imprinted master. 6. The method of claim 5,
In the fitting data, there are several points at which the load suddenly changes,
Wherein the limit load of the tool is determined as a load at a point having a smallest load value among a plurality of points where the load suddenly changes. The method according to claim 1,
The depth of the second concavo-convex pattern is formed on a nanometer scale of 1 nm or more and less than 1,000 nm, and the width of the second concavo-convex pattern is on a nanometer scale of 1 nm or more and less than 1,000 nm or a micrometer scale of 1 μm or more and less than 1,000 μm Wherein the step of forming the imprinting master comprises the steps of: 8. The method of claim 7,
Wherein the substrate is formed of one of a flat plate and a cylindrical shape. 9. The method according to any one of claims 1 to 8,
Wherein the substrate comprises any one selected from the group consisting of silicon, glass, sapphire, and germanium. An uneven pattern made of a brittle material and formed by mechanical scratching,
The depth of the concavo-convex pattern falls within a range of 1 nm or more and less than 1,000 nm,
Wherein the cross-sectional shape of the concavo-convex pattern corresponds to the cross-sectional shape of the tool tip used for the scratch processing. 11. The method of claim 10,
Wherein the brittle material comprises any one selected from the group consisting of silicon, glass, sapphire, and germanium. 11. The method of claim 10,
An imprinting master formed by the imprinting master plate and the imprinting master plate. 11. The method of claim 10,
9. A master for imprinting, produced by the method according to any one of claims 1 to 8, wherein the second concave-convex pattern functions as a concavo-convex pattern for imprinting.

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