JP2015082542A - Roller mold blank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a roller mold blank in which a fine concavo-convex pattern can be formed while suppressing influences of reflected light in exposure for forming the fine concavo-convex pattern.SOLUTION: A roller mold blank 1 includes a rotating body 2 rotatable around a rotation axis O, a patterning layer 3 disposed on an outer periphery of the rotating body 2 along a direction of the rotation axis O, a resist layer 4 disposed on the patterning layer 3, and a light-absorbing layer 5 that absorbs reflected light induced when the resist layer 4 is exposed. The light-absorbing layer 5 is composed of at least a first light-absorbing layer 5a and a second light-absorbing layer 5b, separated from each other. The first light-absorbing layer 5a is disposed between the rotating body 2 and the patterning layer 3 so as to absorb reflected light generated from the rotating body 2; and the second light-absorbing layer 5b is disposed between the patterning layer 3 and the resist layer 4 so as to absorb reflected light generated from the patterning layer 3.

Description

  The present invention relates to a roller mold blank, and more particularly to a roller mold blank for producing a roller mold having an uneven pattern.

  In recent years, attention has been focused on an imprint technique, which is a method for transferring a concavo-convex pattern onto a transfer medium like a stamp using a mold having a concavo-convex pattern formed thereon. By this imprint technique, nano-order microstructures can be produced in large quantities at low cost with good reproducibility.

  Several methods are known as imprint techniques. For example, a batch transfer method that presses the mold and the transfer object at once, or a step-and-repeat method that repeats the above imprint method using a flat plate mold and finally transfers the uneven pattern to a large area substrate Etc.

  On the other hand, using a roller with a concavo-convex pattern in advance on the roller surface as a mold, applying a load to the roller while heating the transfer object with this roller, and rotating this roller, the pattern on the roller surface is transferred to the transfer object There is a roller mold method for transferring images sequentially (for example, see Patent Documents 1 to 3 by the present applicant).

  With this method, the pattern can be transferred onto the transfer target continuously by the repeated rotation of the roller. Therefore, this method is an effective method for pattern transfer to a transfer target having a length of several meters or more.

  However, in the case of the roller mold method, a metal material (for example, stainless steel) is often used as a rotating body that is the basis of the roller mold. For this reason, it is known that when a resist is exposed to form a concavo-convex pattern in a roller mold, light transmitted through the resist is reflected by a rotating body (see [0040] of Patent Document 4).

  In this case, incident light and reflected light interfere with each other, the exposure characteristics fluctuate, and a fine pattern cannot be formed accurately (see [0041] in Patent Document 4). In order to solve the problem, Patent Document 4 discloses a technique in which the surface layer formed on the outer peripheral surface of the rotating body has a refractive index within a predetermined range and an extinction coefficient of a predetermined value or less. (Refer to [0047] of Patent Document 4). It is also disclosed that a light absorption layer is provided between the rotating body and the surface layer (see [0059] of Patent Document 4).

WO2011 / 093356 WO2011 / 093357 Publication JP2013-35243A WO2010 / 140648

  As a result of the study of the technique described in Patent Document 4 above, the following problems have been newly clarified.

  The problem is that even if a light absorption layer is provided between the rotating body and the surface layer, the exposure characteristics still vary. That is, it has been clarified by the study of the present inventor that interference between incident light and reflected light still occurs and hinders formation of a fine uneven pattern.

  An object of the present invention is to provide a roller mold blank capable of suppressing the influence of reflected light during exposure for forming a concavo-convex pattern and forming a fine concavo-convex pattern on a roller mold.

  About this subject, this inventor added earnest examination. As a result, the reflected light is generated not only from the rotating body that is the basis of the roller mold, but also from a new boundary surface formed by the presence of the patterning layer on which the concavo-convex pattern is formed. It has been clarified by the present inventors that the influence of this reflected light cannot be ignored as the pattern becomes finer.

  Based on the above findings, the present inventor has studied a means for suppressing the influence of reflected light from the patterning layer. At first, a technique was considered in which a light absorption layer was provided on a patterning layer and a resist layer was provided on the light absorption layer, instead of providing a light absorption layer on the rotating body. In this way, it was considered that the reflected light from the rotating body and the reflected light from the patterning layer could be absorbed at once by the light absorption layer on the patterning layer.

  When the above idea is realized, it is desired to provide a light absorption layer having a larger film thickness in order to suppress reflected light. On the other hand, considering the pattern line width and pitch required at present, and the aspect ratio (height / width) as high as 1 to 3, the light absorption layer provided on the patterning layer is as much as possible. A thin film thickness is preferable. In order to form a concavo-convex pattern on the patterning layer, the concavo-convex pattern must also be formed on the light absorption layer present thereon. At this time, if the light absorption layer is thick, pattern collapse may occur at the stage where the uneven pattern is formed on the light absorption layer. In this case, the yield is lowered due to a configuration that is not originally related to pattern formation. For this purpose, it is necessary to make the light absorption layer as thin as possible and to obtain a process margin as much as possible.

  When the required pitch of the uneven pattern becomes as fine as about 300 to 500 nm, this trade-off relationship starts to become apparent. Here, in order to control the reflected light, a film thickness of preferably about 150 nm or more is required. However, when forming a desired shape at present, it is extremely difficult or impossible to use a resist pattern as described above, transfer a predetermined uneven pattern to a thick light absorption layer, and then form a pattern on the patterning layer. It is possible.

  As described above, in order to solve the problems relating to “reflected light from the patterning layer” and “thickness of the light absorption layer”, the present inventor uses at least the first light absorption layer as the light absorption layer formed on the rotating body. A new technique has been conceived in which the layer and the second light absorption layer are separated. And by each light absorption layer which became comparatively thin by being constituted separately, the reflected light from the rotating body and the reflected light from another boundary surface such as the patterning layer play a role by each divided light absorption layer. We have come up with an innovative method of sharing and absorbing.

The embodiment of the present invention based on this finding is as follows.
The first aspect of the present invention is:
A rotating body that is a base of a roller mold that is rotatable along a rotation axis;
A layer provided on the outer peripheral portion along the rotation axis direction in the rotating body, the patterning layer serving as a basis for the uneven pattern of the roller mold,
A resist layer provided on the patterning layer;
A light-absorbing layer that absorbs reflected light generated when exposure corresponding to the concavo-convex pattern is performed on the resist layer;
A roller mold blank having
The light absorption layer is composed of at least a first light absorption layer and a second light absorption layer,
The first light absorption layer is provided between the rotating body and the patterning layer to absorb reflected light generated from the rotating body,
The second light absorption layer is a roller mold blank provided between the patterning layer and the resist layer so as to absorb reflected light generated from the patterning layer.
A second aspect of the present invention is the aspect described in the first aspect,
The thickness of the first light absorption layer is 30 nm or more, and the thickness of the second light absorption layer is 100 nm or less.
A third aspect of the present invention is the aspect described in the first or second aspect,
The first light absorption layer and the second light absorption layer are made of nitrogen carbide.
A fourth aspect of the present invention is the aspect according to any one of the first to third aspects,
The patterning layer is made of polysilazane.
A fifth aspect of the present invention is the aspect according to any one of the first to fourth aspects,
The rotating body is made of stainless steel or quartz.

  ADVANTAGE OF THE INVENTION According to this invention, the influence by reflected light can be suppressed in the exposure for forming an uneven | corrugated pattern, and the roller mold blank which can form a fine uneven | corrugated pattern in a roller mold can be provided.

It is the schematic of the roller mold in this embodiment, (a) is a perspective view of the roller mold 101, (b) is sectional drawing of the AA 'part of (a), (c) is B- of (a). It is sectional drawing of a B 'part. It is a section schematic diagram of a roller mold blank in this embodiment. It is a cross-sectional schematic diagram which shows the manufacturing method of the roller mold in this embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the present embodiment, description will be given in the following order.
1. 1. Outline of roller mold Composition of roller mold blank
2-A) Rotating body 2-B) First light absorption layer 2-C) Patterning layer 2-D) Second light absorption layer 2-E) Resist layer 2-F) Others (antireflection layer, adhesion enhancement) Layer and elastic layer)
3. 3. Method for Producing Roller Mold 3-A) Preparation of Roller Mold Blank 3-B) Exposure Step 3-C) Development Step 3-D) Concave / Pattern Formation Step for Patterning Layer 3-E) Cleaning / Drying Step 4. Effects of the embodiment Modifications etc. In addition, about the structure which is not described below, you may employ | adopt suitably a well-known structure (For example, the structure as described in patent documents 1-3 by this applicant). The contents described in Patent Documents 1 to 3 and related to the present embodiment are described in this specification.

<1. Outline of Roller Mold>
The present embodiment relates to a roller mold blank that is a base for manufacturing a roller mold. Before describing the roller mold blank, first, an outline of the roller mold 101 in a completed form will be described with reference to FIG. FIG. 1 is a schematic view of a roller mold 101, (a) is a perspective view of the roller mold 101, (b) is a cross-sectional view of the AA 'portion of (a), (c) is a B- of (a). It is sectional drawing of a B 'part.

  As described in Patent Documents 1 to 3 by the present applicant, the roller mold 101 in the present embodiment is a rotary cylindrical mold used for imprinting. The roller mold 101 includes two end portions (102a and 102b, collectively referred to as reference numeral 102 hereinafter) through which the rotation axis O passes, and a portion sandwiched between the two end portions 102 in the direction of the rotation axis O. And an outer peripheral portion 103 extending along the line. A predetermined pattern is formed on the main surface of the outer peripheral portion 103. The predetermined pattern mentioned here is a pattern configured by a periodic uneven shape. In the present embodiment, there is a concavo-convex pattern formed from the patterning layer on the outer periphery of the cylindrical rotating body.

  In the following description, “′” as a reference sign indicates a pattern in which a concavo-convex pattern is formed. As a specific example, in FIGS. 2 and 3 to be described later, a pattern having a concavo-convex pattern formed on the patterning layer 3 is referred to as a “concave / convex pattern 3 ′”, and the concavo-convex pattern was formed on the resist layer 4. This is referred to as “resist pattern 4 ′”.

  Further, a rotation auxiliary portion 104 is provided along the rotation axis O at the two end portions 102 of the roller mold 101. This is the portion that contacts the roller mold rotating roll 105 for rotating the roller mold 101. The rotation of the roller mold rotating roll 105 is transmitted to the rotation assisting unit 104, and as a result, the roller mold 101 integrated with the rotation assisting unit 104 can be rotated.

<2. Configuration of Roller Mold Blank 1>
In order to manufacture the roller mold 101 as described above, in this embodiment, a roller mold blank 1 having the following configuration is used. This will be described below with reference to FIG. 2 which is a schematic sectional view of the roller mold blank 1.
The rotating body 2 that is the basis of the roller mold 101 that is rotatable along the rotation axis O
A patterning layer 3 which is a layer provided on the outer peripheral portion 103 along the direction of the rotation axis O in the rotating body 2 and serves as a basis for the uneven pattern 3 ′ of the roller mold 101.
A resist layer 4 provided on the patterning layer 3

The above configuration is marked in the order of stacking. That is, the patterning layer 3 is provided on the outer peripheral portion 103 of the rotating body 2, and the resist layer 4 is provided on the patterning layer 3. In this specification, the meaning of “B is provided on A” also means that “B is provided so as to cover A”. More specifically, the above expression includes the case where B is laminated immediately above A, and there is a case where another layer is laminated immediately above A and B is laminated immediately above the other layer. Including. In the case of the present embodiment, the description is made on the assumption that the layers are stacked in the top-to-bottom direction. Therefore, although the expression “on top” is used for convenience, even if the stacking is performed in the direction of the top and bottom, it means that “B is provided so as to cover A”. does not change. Therefore, even if the stacking is performed in the direction of the top and bottom, the expression “B is provided on A” may be used.
That is, in the present embodiment, the patterning layer 3 is provided on the outer peripheral portion 103 along the rotation axis direction in the rotating body 2. However, the expression “the patterning layer 3 is provided so as to cover the outer peripheral portion 103 of the rotating body 2” includes the case where the patterning layer 3 completely covers the outer peripheral portion 103, and at the end of the roller mold 101. Includes the case where the patterning layer 3 is not formed, and the patterning layer 3 is formed only in the main part used for transferring the concavo-convex pattern 3 ′ in the outer peripheral part 103.

  In the present embodiment, a resist pattern 4 ′ is formed from the resist layer 4 by exposing and developing the roller mold blank 1 having the above-described configuration. Thereafter, an uneven pattern 3 ′ is formed on the patterning layer 3 using the resist pattern 4 ′ as a mask.

In addition, in this embodiment,
A light absorbing layer 5 that absorbs reflected light generated when exposure corresponding to the uneven pattern 3 ′ is performed on the resist layer 4
Also have.

  And one of the characteristic points in this embodiment is that the light absorbing layer 5 is separately arranged in the roller mold blank 1.

Specifically, the light absorption layer 5 is constituted by being divided at least by the first light absorption layer 5a and the second light absorption layer 5b. The first light absorption layer 5 a is provided between the rotating body 2 and the patterning layer 3 so as to absorb the reflected light generated from the rotating body 2. The second light absorption layer 5 b is provided between the patterning layer 3 and the resist layer 4 so as to absorb the reflected light generated from the patterning layer 3. The above content has one of the features of this embodiment.
Each configuration will be described below. Hereinafter, each structure will be described in the order of the structures stacked on top of the rotating body 2 that is the basis of the roller mold blank 1, that is, in the stacking order.

2-A) Rotating body 2
As long as the rotating body 2 can be used as the roller mold 101, a known configuration may be used. For example, stainless steel (SUS), aluminum, or quartz may be used as the material. Also, the shape may be cylindrical or other shapes may be used.

  Although it is advantageous in terms of cost to use stainless steel or aluminum, it is preferable to use quartz in view of suppressing reflection from the rotating body 2 as much as possible. Certainly, reflected light from the rotating body 2 can be absorbed by a first light absorption layer 5a described later. However, there is a limit to the intensity of light that can be absorbed. For this reason, it has never been possible to suppress reflection from the rotating body 2 as much as possible. Therefore, it is particularly preferable to use quartz as the rotating body 2.

2-B) First light absorption layer 5a
In this embodiment, one of the major features is that the first light absorption layer 5a and the second light absorption layer 5b described later are provided by dividing the conventional light absorption layer into a plurality of parts. When exposure corresponding to the uneven pattern 3 ′ is performed on the roller mold blank 1, reflected light is generated from the rotating body 2. In order to form a precise resist pattern 4 ', it is necessary to absorb this reflected light. Therefore, the reflected light is absorbed by the first light absorption layer 5a.

The first light absorption layer 5a has a light absorption function at the wavelength of the exposure light, and absorbs the reflected light from the patterning layer 3 while absorbing the reflected light from the rotating body 2. As long as the resist pattern 4 ′ can be precisely formed by cooperation with the layer 5b, a known configuration may be used. For example, the material may be carbon, transition metal (for example, chromium), oxides, nitrides, sulfides thereof, or a mixture thereof. Moreover, you may use the organic adhesive agent which used these substances as a filler. However, it is preferable to use nitrogen carbide because appropriate light absorption can be performed by relatively thin film formation. On the other hand, an elastic black elastomer may be used as the first light absorption layer 5a.
Hereinafter, an example in which the first light absorption layer 5a and the second light absorption layer 5b are made of nitrogen carbide (CN) will be described.

The thicknesses of the first light absorption layer 5a and the second light absorption layer 5b are set according to the relationship between the reflectance of the rotating body 2 and the reflectance of the patterning layer 3 when the exposure light is irradiated. You can decide. For example, when stainless steel is used as the material of the rotating body 2 and polysilazane is used as the material of the patterning layer 3, stainless steel has a higher reflectance. In this case, it is preferable to increase the absorption degree of the reflected light by increasing the thickness of the first light absorption layer 5a on the rotating body 2.
In addition, it is desirable to increase the thickness of the second light absorption layer 5b in consideration of leakage light that cannot be absorbed by the first light absorption layer 5a. On the other hand, if the thickness of the second light absorption layer 5b is excessively increased, the fine uneven pattern 3 ′ cannot be stably formed.
Therefore, the second light absorption layer 5b on the patterning layer 3 is formed relatively thin. In this case, it is preferable to make the thickness of the first light absorption layer 5a larger than the thickness of the second light absorption layer 5b. In addition, as a numerical range, it is preferable that the thickness of the 1st light absorption layer 5a shall be 30-300 nm, and the thickness of the 2nd light absorption layer 5b shall be 30-100 nm.
Therefore, even if the thickness of the first light absorption layer 5a is made smaller than the thickness of the second light absorption layer 5b and the patterning characteristics are taken into consideration, the thickness of the second light absorption layer 5b is 100 nm or less. I do not care. And the thickness of the 1st light absorption layer 5a should just be set from the point of productivity and pattern intensity, if the influence of the reflection from a base material is prevented, for example, 30 nm or more is desirable.

  However, conversely, the thickness of the first light absorption layer 5a may be smaller than the thickness of the second light absorption layer 5b. As described above, even if the first light absorption layer 5a cannot completely absorb the reflected light from the rotating body 2, if the second light absorption layer 5b finally exists with a sufficient thickness, The interference between the emitted light and the reflected light can be suppressed.

2-C) Patterning layer 3
As long as the patterning layer 3 can become the uneven | corrugated pattern 3 'provided in the roller mold 101, you may use a well-known structure. For example, a Si thin film, a SiO ₂ thin film, or polysilazane may be used as the material.

2-D) Second light absorption layer 5b
The second light absorption layer 5b has a light absorption function at the wavelength of the exposure light, and absorbs the reflected light from the rotating body 2 while absorbing the reflected light from the patterning layer 3. As long as the resist pattern 4 ′ can be precisely formed in cooperation with the layer 5a, a known configuration may be used. Others are the same as described in 2-B) the first light absorption layer 5a.

  However, the second light absorption layer 5b has the following special effects. <3. Although it is also related to the manufacturing method of the roller mold 101>, the resist pattern 4 ′ is formed from the resist layer 4, and then the unevenness is also formed in the second light absorption layer 5b using the resist pattern 4 ′ as a mask. The Thereafter, an uneven pattern 3 ′ is also formed on the patterning layer 3. Thereafter, the resist pattern 4 ′ is peeled off, but the second light absorption layer 5 b remains on the uneven pattern 3 ′ in the patterning layer 3. In this state, by inspecting the concavo-convex pattern 3 ′, the inspection can be performed more accurately and easily than in the case of inspecting the concavo-convex pattern 3 ′ in the patterning layer 3. This is because, when inspecting with an optical system, when the patterning layer 3 is polysilazane, it is very difficult to recognize the uneven pattern 3 ′ because polysilazane has high transparency. However, when the second light absorption layer 5b is made of a material having low transparency (for example, nitrogen carbide), the concave / convex pattern 3 ′ can be confirmed in a state where the second light absorption layer 5b exists. It becomes possible. When inspecting with an SEM (scanning electron microscope), the light absorption layer 5b, which is a material different from polysilazane, is present on the pattern top (above the convex portion of the concave / convex pattern 3 ′), so that the pattern edge boundary portion in the SEM image. Can be captured with different tones. As a result, the uneven pattern 3 ′ can be inspected accurately and easily.

  The second light absorption layer 5b may be made of a material different from that of the first light absorption layer 5a. For example, this is a case where an elastic black elastomer is used as the first light absorption layer 5a, and the first light absorption layer 5a is formed thick, for example, at 100 nm or more.

2-E) Resist layer 4
The resist layer 4 may have a known configuration as long as the concavo-convex pattern 3 ′ can be formed by exposure. For example, the resist layer 4 may be formed by applying a resist on the second light absorption layer 5b and then baking. The type of resist may be arbitrary. For example, a heat-reactive resist using heat generated by exposure may be used, or a photoreactive resist may be used. Moreover, there is no restriction | limiting also about the composition of each resist. In the present embodiment, a case where a heat-reactive inorganic resist composed of an inorganic compound, specifically tungsten oxide (WO _x ), is used as the heat-reactive resist.

  The resist layer 4 using tungsten oxide is a positive-type heat-sensitive material that changes its state by thermal change when exposed to blue laser light, and is preferable from the viewpoint of improving resolution. Furthermore, the resist layer 4 is suitable for an etching process performed to form the uneven pattern 3 ′. Therefore, it is preferable in this embodiment that the resist layer 4 using tungsten oxide is used. In addition, the resist layer 4 using tungsten oxide has a high transmittance with respect to exposure light (for example, blue laser light), and the amount of light reaching the patterning layer 3 and the rotating body 2 increases. Therefore, the above-described reflection problem is likely to occur. However, by adopting a configuration in which the light absorption layer is separately provided on the rotating body 2 and the patterning layer 3 as in the present embodiment, there are disadvantages when the resist layer 4 using tungsten oxide is employed. It can be eliminated and only the merit can be enjoyed.

  The “exposure” referred to here may use a known method as long as it can form a resist pattern 4 ′ having unevenness by causing a difference in solubility when developing the resist layer 4. For example, you may use exposure using the mask which has a shape corresponding to the uneven | corrugated pattern 3 'to be finally formed, and it exposes so that it may draw with respect to the roller mold blank 1 with the laser which has a predetermined wavelength. You can go. In this embodiment, a case where exposure is performed by laser drawing will be described.

2-F) Others (antireflection layer, adhesion reinforcing layer and elastic layer)
Said structure is a minimum required structure in the roller mold blank 1 of this embodiment. Of course, you may provide the roller mold blank 1 with structures other than said structure.

  For example, an antireflection layer using interference between incident light and reflected light may be provided on the roller mold blank 1. Due to the presence of the antireflection layer, it is possible to eliminate the influence of the reflected light on the first light absorption layer 5a and the second light absorption layer 5b. An antireflection layer may be disposed between the patterning layer 3 and the resist layer 4 in order to use the antireflection layer as a post-packaging for eliminating the influence of reflected light. The antireflection layer is preferably disposed between the second light absorption layer 5 b and the resist layer 4. In that case, the antireflection layer may have the same effect as described in the second light absorption layer 5b. That is, it is possible to check the uneven pattern 3 ′ in a situation where an antireflection layer exists. As a result, the uneven pattern 3 ′ can be inspected accurately and easily.

A known antireflection layer may be used. For example, a material containing chromium oxide (CrO) may be used. Although it is difficult to completely suppress the reflected light with only the antireflection layer using interference, the process of using the chromium oxide with good pattern transfer characteristics can reduce the thickness of the CN layer on the upper layer. The possibility of earning a margin can be expected. The antireflection layer may have the same configuration as the first light absorption layer 5a and the second light absorption layer 5b. Note that <5. Modification> As will be described later, a third light absorption layer or a fourth light absorption layer may be provided to interfere with the reflected light and reduce the influence of the reflected light.
If a third light absorption layer or a fourth light absorption layer is provided to reduce the influence of reflected light instead of the antireflection layer, the thickness of each light absorption layer existing on the patterning layer 3 is 100 nm. The following is preferable.
If an antireflection layer is provided separately from the light absorption layer 5, the total thickness of the light absorption layer 5 as described above does not include the thickness of the antireflection layer.

  Moreover, in order to strengthen the adhesive force between each layer, you may provide an adhesion reinforcement layer in the roller mold blank 1 separately. As the adhesion reinforcing layer, a known layer may be used as long as it can reinforce the adhesive force between the layers. However, for example, it includes at least one of Si and tungsten (W). The adhesion reinforcement layer comprised by these is mentioned.

  Moreover, the resist layer 4 using tungsten oxide has a high transmittance with respect to exposure light, and in some cases, the heat of the laser is not stored well in the resist layer 4. As a countermeasure, a heat absorption layer may be provided for the resist layer 4. As the heat absorbing layer, a known layer may be used as long as it absorbs the heat of the exposure light when irradiated with the exposure light and can be transmitted to the resist layer 4.

  Furthermore, a functional layer (elastic layer) for giving elasticity like an elastomer may be provided under the patterning layer 3. In addition, as above-mentioned, you may use as the light absorption layer 5a by using a black elastomer.

<3. Manufacturing method of roller mold 101>
Next, the manufacturing method of the roller mold 101 in this embodiment is demonstrated using FIG.
FIG. 3 is a schematic cross-sectional view showing a method for manufacturing the roller mold 101 in the present embodiment.
The contents of the following steps are <2. There is a part which overlaps with the contents explained in <Configuration of Roller Mold Blank 1>. Therefore, for contents not described below, <2. It is as having demonstrated by the structure of roller mold blank 1.

3-A) Preparation of Roller Mold Blank 1 In order to form the roller mold 101 in the present embodiment, first, the rotation axis O that is not physically formed, the two end portions 102 through which the rotation axis O passes, the rotation A roller mold blank 1 having a cylindrical structure having an outer peripheral portion 103 along the axial direction is prepared. In addition, as a formation method of the rotary body 2 which comprises the roller mold blank 1, and each layer, you may use a well-known method. For example, for the first light absorption layer 5a and the second light absorption layer 5b, nitrogen carbide may be formed by sputtering. The patterning layer 3 may be coated with polysilazane as described in Patent Document 3. In the case of this embodiment, the application target of polysilazane in Patent Document 3 is “the rotator 2 in which the first light absorption layer 5 a is provided on the outer peripheral portion 103”. As for the resist layer 4, tungsten oxide may be formed by sputtering.

3-B) Exposure process The uneven | corrugated pattern 3 'is drawn and exposed with respect to said roller mold blank 1 using a blue laser drawing apparatus. In this exposure, a known method may be used.

3-C) Development Step Thereafter, development is performed on the exposed resist layer 4 to obtain a resist pattern 4 ′ having a desired uneven pattern 3 ′.

3-D) Concavity and convexity pattern 3 ′ forming step for patterning layer 3 After applying concavity and convexity pattern 3 ′ to resist layer 4 to form resist pattern 4 ′ as described above, patterning layer 3 is formed using resist layer 4 as an etching mask. Etching is performed on the substrate. For this etching process, a known etching method may be used according to the patterning layer 3. For example, dry etching using a fluorine-based gas or wet etching using hydrofluoric acid can be used.
By this etching process, the rotating body 2 having a desired uneven pattern 3 ′ is obtained.

  A predetermined uneven pattern is also formed on the second light absorption layer 5b to form the second light absorption layer 5b '. As described above, in the present embodiment, since the second light absorption layer 5b is composed of nitrogen carbide, the confirmation of the concave / convex pattern 3 ′ is performed in a state where the second light absorption layer 5b ′ exists. Is possible. As a result, the uneven pattern 3 ′ can be inspected accurately and easily.

3-E) Washing / Drying Step Thereafter, the resist pattern 4 ′ and the second light absorption layer 5b ′ are removed. A known method may be used as the removal method. Then, after the resist pattern 4 ′ and the second light absorption layer 5b ′ are removed, the rotating body 2 is subjected to pure water cleaning and vapor drying with isopropanol. Thereby, the roller mold 101 by which the desired uneven | corrugated pattern 3 'was transcribe | transferred to the outer peripheral part 103 of the rotary body 2 can be produced.

  In addition, you may form a predetermined uneven | corrugated pattern with respect to the 1st light absorption layer 5a. Moreover, you may form an uneven | corrugated pattern in the rotary body 2 itself. In that case, the concavo-convex pattern 3 ′ and the first light absorption layer 5 a are not necessary and are removed.

<4. Advantages of the embodiment>
According to this embodiment, the following effects can be obtained.

  First, of the two problems “reflected light from the patterning layer 3” and “thickness of the light absorbing layer” that have been clarified by the present inventors, the “reflected light from the patterning layer 3” is the conventional light absorbing layer. Is taking measures to divide the One of the divided light absorption layers is provided on the rotating body 2 that is one of the causes of reflected light, and the other is on the patterning layer 3 that is one of the causes of reflected light. The provision solves the problem.

  In addition, with respect to the other problem “thickness of the light absorption layer”, the thickness of each light absorption layer is reduced by dividing the conventional light absorption layer into two as compared with the case of having one light absorption layer. can do. By doing so, each light absorption layer can absorb the reflected light from the rotating body 2 and the reflected light from the patterning layer 3 without providing a thick light absorption layer on the patterning layer 3. Furthermore, since the thickness of each light absorption layer can be made relatively small, the period of the concavo-convex pattern 3 ′ can be ensured without causing an aspect ratio problem between the thickness of the light absorption layer and the period of the concavo-convex pattern 3 ′. It can be very fine.

  As described above, according to the present embodiment, the roller mold blank 1 capable of suppressing the influence of reflected light and forming the fine uneven pattern 3 ′ on the roller mold 101 during the exposure for forming the uneven pattern 3 ′. Can provide.

<5. Modified example>
The technical scope of the present invention is not limited to the above-described embodiments, but includes forms to which various modifications and improvements are added within the scope of deriving specific effects obtained by the constituent features of the invention and combinations thereof. .
Hereinafter, modifications other than the above will be listed.

(3rd, 4th light absorption layer)
In the above embodiment, the example in which the light absorption layer is divided into two parts has been described. Of course, a third, fourth or higher nth (n is a natural number) light absorbing layer may be provided on the roller mold blank 1. For example, when reflected light is generated by the adhesion enhancing layer, a third light absorbing layer may be provided on the adhesion enhancing layer. When providing the layer which produces reflected light in the roller mold blank 1, you may provide a 3rd light absorption layer on the layer.

(Other layers constituting the roller mold blank 1)
In the above embodiment, the antireflection layer and the adhesion reinforcing layer have been described as examples of the layers constituting the roller mold blank 1. On the other hand, a layer other than the antireflection layer or the adhesion reinforcing layer may be provided between the rotating body 2 and the resist layer 4. Examples of this other layer include a hard mask including a conductive layer and an antioxidant layer, and an adhesion layer. Note that the “hard mask” here refers to a layered layer composed of a single layer or a plurality of layers and used for etching a groove on a substrate. Note that the antioxidant layer in the hard mask may also serve as a conductive layer. In that case, the conductive layer can be omitted.

(Working replica)
In the above-described embodiment, an example in which the roller mold 101 serving as a master is manufactured has been described. In addition to this, the concave / convex pattern 3 ′ of the roller mold 101 serving as a master may be transferred to a film-like transferred body, and the transferred body may be wound around another rotating body 2 to produce a working replica. Furthermore, the working replica may be formed by bringing the transferred body into contact with the rotating body 2 on which the resist layer 4 is formed and transferring the uneven pattern 3 ′. Even if the working replica is deformed / damaged, the working replica can be accurately manufactured if the roller mold 101 serving as the master is safe.

(Pattern shape)
In addition, any shape can be used as the shape of the uneven pattern 3 ′ of the present embodiment. For example, when manufacturing a master for producing a magnetic medium (Bit Patterned Media) for recording a signal as a bit pattern (dot pattern), the shape of the dots may be rectangular or other shapes. Absent. Further, a linear pattern may be used in a plan view, such as a discrete track recording media (Discrete Track Recording Media) formed by magnetically separating data tracks of a magnetic disk. May be mixed.

  Furthermore, although it is the order of the specific period of this uneven | corrugated pattern 3 ', although the pattern of the range from nano order to micro order (period less than 1 micrometer) may be sufficient, the performance of electronic devices in recent years and final products From the viewpoint of performance, it is even better if it is a nano-order periodic structure of several nm to several hundred nm. If specific numerical values are given, it is preferable to use the roller mold blank 1 in order to form the concavo-convex pattern 3 ′ having a period of 350 nm or less.

(Aspect using an antireflection layer instead of the light absorption layer 5)
In said embodiment, the structure which divided | segmented the light absorption layer 5 into 2 is employ | adopted. On the other hand, even if an antireflection layer is used in place of the light absorption layer 5, the above-described problems can be solved and the above-described effects can be achieved.
A summary of the above contents is as follows.

A rotating body that is a base of a roller mold that is rotatable along a rotation axis;
A layer provided on the outer peripheral portion along the rotation axis direction in the rotating body, the patterning layer serving as a basis for the uneven pattern of the roller mold,
A resist layer provided on the patterning layer;
An antireflection layer for suppressing the generation of reflected light when performing exposure corresponding to the uneven pattern on the resist layer;
A roller mold blank having
The antireflection layer is composed of at least a first antireflection layer and a second antireflection layer,
The first antireflection layer is provided between the rotating body and the patterning layer in order to suppress generation of reflected light from the rotating body,
The second antireflection layer is a roller mold blank provided between the patterning layer and the resist layer in order to suppress generation of reflected light from the patterning layer.

(Combination of the patterning layer 3 with high transparency and the light absorption layer 5 with low transparency)
In the above embodiment, the example in which the light absorption layer 5 is divided into at least two has been described. On the other hand, it is a problem found by the present inventors that the reflected light from the patterning layer 3 affects the formation of the fine uneven pattern 3 ′. In order to solve this problem, the light absorption layer 5 may be provided on the patterning layer 3 instead of providing the light absorption layer 5 on the rotating body 2. However, as described in the knowledge of the present invention, the thickness of the light absorption layer 5 is preferably 100 nm or less. In addition, when the patterning layer 3 (polysilazane) has transparency and the light absorption layer 5 (nitrogen carbide) has a relatively low transparency, the concavo-convex pattern 3 ′ can be inspected accurately and easily. The roller mold blank 1 having such a patterning layer 3 and a light absorption layer 5 also has the above-mentioned unique problems and effects.
A summary of the above contents is as follows.

A rotating body that is a base of a roller mold that is rotatable along a rotation axis;
A layer provided on the outer peripheral portion along the rotation axis direction in the rotating body, the patterning layer serving as a basis for the uneven pattern of the roller mold,
A resist layer provided on the patterning layer;
A light-absorbing layer that absorbs reflected light generated when exposure corresponding to the concavo-convex pattern is performed on the resist layer;
A roller mold blank having
The light absorption layer is provided between the patterning layer and the resist layer in order to absorb reflected light generated from the patterning layer,
A roller mold blank in which the light absorption layer is less transparent than the patterning layer.

  Even if the “light absorption layer” in the above configuration is replaced with an “antireflection layer”, the above-described unique problems exist and there are also unique effects. The above contents can also be applied to the relationship of transparency between the first light absorption layer 5a and the second light absorption layer 5b and the patterning layer. In other words, the above-described effects can be obtained by making the transparency of the first light absorption layer 5a and the second light absorption layer 5b lower than the transparency of the patterning layer.

(Application of the present invention to other than the roller mold 101)
In the above embodiment, absorption of reflected light in the roller mold 101 has been described. On the other hand, the present invention can be applied to other than the roller mold 101. In other words, if the light absorbing layer is divided, the structure can absorb each reflected light, such as absorption of reflected light to the “base material” and absorption of reflected light to the “patterning layer 3”. The present invention can be applied. As an example close to the roller mold 101, the present invention is naturally applicable to a flat imprint mold blank used for step and repeat. Eventually, reflected light is generated by exposure, and the present invention is applicable to a technical field in which the problem that the uneven pattern 3 ′ cannot be precisely formed occurs.
A summary of the above contents is as follows.

A base material on which the structure is based;
A layer provided on the base material, the patterning layer serving as a base of the concavo-convex pattern of the structure;
A resist layer provided on the patterning layer;
A light-absorbing layer that absorbs reflected light generated when exposure corresponding to the concavo-convex pattern is performed on the resist layer;
A structure having
The light absorption layer is composed of at least a first light absorption layer and a second light absorption layer,
The first light absorption layer is provided between the substrate and the patterning layer to absorb reflected light generated from the substrate,
The second light absorption layer is a structure provided between the patterning layer and the resist layer so as to absorb reflected light generated from the patterning layer.

  The structure having the above-described structure has a very advantageous effect of suppressing the influence of reflected light and having a fine concavo-convex pattern during exposure for forming the concavo-convex pattern.

DESCRIPTION OF SYMBOLS 1 ......... Roller mold blank 2 ......... Rotating body 3 ......... Pattern layer 3 '... Uneven pattern 4 ......... Resist layer 4' ... Resist pattern 5 ......... Light absorption layer 5a ... First Light Absorbing Layer 5b ... Second Light Absorbing Layer 101 ... Roller Mold 102 ... End 103 ... Outer Peripheral 104 ... Rotation Auxiliary Part 105 ... Roll Mold Roll O ...

Claims (5)

A rotating body that is a base of a roller mold that is rotatable along a rotation axis;
A layer provided on the outer peripheral portion along the rotation axis direction in the rotating body, the patterning layer serving as a basis for the uneven pattern of the roller mold,
A resist layer provided on the patterning layer;
A light-absorbing layer that absorbs reflected light generated when exposure corresponding to the concavo-convex pattern is performed on the resist layer;
A roller mold blank having
The light absorption layer is composed of at least a first light absorption layer and a second light absorption layer,
The first light absorption layer is provided between the rotating body and the patterning layer to absorb reflected light generated from the rotating body,
The second light absorption layer is a roller mold blank provided between the patterning layer and the resist layer so as to absorb reflected light generated from the patterning layer.   The roller mold blank according to claim 1, wherein the thickness of the first light absorption layer is 30 nm or more, and the thickness of the second light absorption layer is 100 nm or less.   The roller mold blank according to claim 1 or 2, wherein the first light absorption layer and the second light absorption layer are made of nitrogen carbide.   The roller mold blank according to claim 1, wherein the patterning layer is made of polysilazane.   The roller mold blank according to claim 1, wherein the rotating body is made of stainless steel or quartz.

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