TWI513566B - Manufacturing method of forming mold - Google Patents

Description

Manufacturing method of forming mold

The present invention relates to a method of manufacturing a forming die and a forming die.

For a display member such as a liquid crystal display device, a recording medium such as a DVD, a mobile phone device, or a biochip such as a DNA wafer, a molded article having a fine uneven structure centering on a micron order and a submicron order is used, and the molded article is formed. The material of the molded article may be resin, enamel or glass.

Examples of the method of forming the resin molded article having such a fine uneven structure include injection molding, nanoimprint molding, emboss molding, roll transfer molding, and the like. Moreover, as a method of forming the tantalum molded article having the fine uneven structure, dry etching and wet etching of tantalum are exemplified. In addition, examples of the method of forming the glass molded article having the fine uneven structure include dry etching of glass and wet etching.

Among these methods, a resin molding method using a mold having a fine uneven structure on the surface is used as a method for producing a general-purpose member, and it is low-cost and has been widely used. According to this resin molding method, a molding die having a structure corresponding to the fine uneven structure of the product is used. By injecting a resin into the molding die, a resin molded article having a fine uneven structure on the surface can be obtained. When the molding die is formed of a metal material having durability, a large number of resin molded articles can be obtained from one molding die, and low cost can be achieved.

The method for producing a molding die formed of such a metal material includes: (1) forming a fine concavo-convex structure by using a resist material that reacts with active energy light such as X-ray, electron beam, laser light, or ultraviolet light; After the concavo-convex pattern) (hereinafter, also referred to as lithography for short), a method of depositing metal by electroplating to obtain a molding die; (2) after directly cutting a metal or glass to form a fine concavo-convex structure, by electroplating a method of depositing a metal to obtain a molding die; (3) a method of depositing a metal by electroplating to obtain a molding die after etching a crucible or glass to form a fine concavo-convex structure; and (4) a metal for directly cutting a mold A method of forming a fine uneven structure or the like.

In view of the size, the degree of freedom of the shape, the in-plane uniformity, and the cost of the fine concavo-convex structure (concave-convex pattern), a method of manufacturing a molding die by lithography and electroplating is preferable. A molding die manufactured by a method of manufacturing a molding die by lithography and electroplating, which is a process of resin molding, is called a LIGA process and has been widely used.

As shown in FIGS. 2A to 2E, an example of a manufacturing process of a molding die used in the LIGA process is a master molding step (Fig. 2A), an energization film forming step (Fig. 2B), and a reinforcing layer forming step ( The second step (Fig. 2C) and the master mold removing step (Fig. 2D) are performed, and a smoothing step (Fig. 2E) may be added as the case may be.

In the master mold forming step (FIG. 2A) of the first step, a concave-convex pattern (resistant structure) 31 obtained from a resist is formed on the substrate 32. The substrate may be a flat substrate such as glass or tantalum, and a resist film is formed on the substrate 32, and is formed by irradiating active energy light, for example, UV light (365 nm), by the contrast of dissolution/non-dissolution of the resist film. The mold is based on a resist-based fine concavo-convex pattern 31.

Next, in the energization film forming step (Fig. 2B) of the second step, the electrification film 33 is formed on the entire surface of the substrate 32 and the concavo-convex pattern 31 obtained in the first step. The energization film forming step (Fig. 2B) is a step of imparting conductivity (conductivity) to the surface of the entire surface of the master mold by metal vapor deposition or electroless plating. In the energization film forming step (Fig. 2B), it is preferable to appropriately reduce the electric resistance of the plating current, so that the film is usually about 0.1 to 0.3 μm.

Next, in the reinforcing layer forming step of the third step, the plating layer 34 is formed on the conductive film 33 by the dielectric film 33 of the substrate 32 obtained in the second step.

This reinforcing layer forming step is substantially a plating step for uniformly depositing a metal on the surface of the resist-based fine uneven pattern 31, for example, on the surface of a plating layer (film thickness) 34 of a metal of 300 μm (as a mold) On the opposite side of the molding surface, the surface of the back surface 34a is formed with a concavo-convex structure indicated by the reference numeral 34b reflecting the fine concavo-convex structure of the master mold.

In other words, a fine concavo-convex structure corresponding to the master mold is formed on the molding surface of the mold, and a fine concavo-convex structure 34b reflecting the concavo-convex pattern 31 of the master mold is formed on the back surface 34a on the opposite side. Among them, it is reflected that the master mold has the same shape as the master mold, but strictly speaking, it is not completely the same shape. That is, the concavo-convex structure 34b of the back surface 34a does not have the same height as the concavo-convex pattern 31, and for example, the height is slightly lower, or the width is smaller or larger, and the same is not the same.

Next, in the master mold removing step (Fig. 2D) of the fourth step, the substrate 32 and the resist structure 31 are removed from the plating layer 34 obtained in the third step, and the mold 40 is produced. The mold 50 for flattening the back surface 34a may be formed by adding a smoothing step (Fig. 2E), wherein the smoothing step removes the uneven structure 34b on the back surface of the mold 40 by polishing or the like.

When molding is performed using a mold (the above-described mold 40) having irregularities on the back surface of the fine concavo-convex structure of the master mold, the mold is easily deformed by the unevenness on the back surface, and the moldability is remarkably deteriorated, or the molding is performed. The surface side of the product has a problem corresponding to the transfer mark of the unevenness on the back surface of the mold. In order to solve this problem, a method of planarizing the back surface polishing (Patent Document 1) or a method of flattening an epoxy resin or the like into the unevenness of the back surface has been reviewed.

[Patent Document 1] Japanese Patent Laid-Open No. 62-232733

However, in the molding die (the above-described mold 50) obtained by the back grinding, since the metal is thermally extended by the polishing for removing the uneven structure 34b of the back surface 34a, the flatness of the molding surface of the molding die is significantly changed. Poor question.

On the other hand, in the molding die obtained by filling the resin into the back surface, there is a problem that the moldability is deteriorated due to a decrease in heat conduction, and the durability is deteriorated due to deterioration or peeling of the filler resin.

The present invention has been made in order to solve the above problems, and an object of the invention is to provide a molding die having a molding die on which a molding surface based on a fine uneven structure of a master mold is transferred, which can ensure the planarity of the molding surface and Durable.

The inventors of the present invention have deliberately studied the above-mentioned problems corresponding to the problems, and formed a convex structure based on a resist by lithography on a substrate having an energized film, and constructed of a substrate and a resist. The body forms a concave-convex structure as a master. Then, by electroforming, only the metal having the same height as the convex structure based on the resist is deposited on the substrate on which the resist is not formed. Then, electroforming is performed on the surface of the substrate by the energization film, and the mold which can be energized by the master mold (hereinafter referred to as a current-carrying substrate) and the convex structure based on the resist are removed to obtain a stamper (forming mold) ). The back surface of the stamper produced by such a step is flat, and it is not necessary to grind or fill the resin. Therefore, it has been found that a molding die excellent in planarity and uniform in thermal conductivity can be obtained.

That is, the present invention is a method for producing a molding die having a fine uneven structure on a molding surface, and the method comprises the following steps.

In the master mold forming step (first step), a conductive substrate having an energization portion on at least one surface of the substrate is used, and a fine convex resist structure based on a resist is applied to the current-carrying portion to form a master mold.

In the metal structure forming step (second step), a metal having a thickness corresponding to the height of the resist structure is deposited in the current-carrying portion, thereby forming a metal structure.

In the energization film forming step (third step), an energization film is formed on the surface of the resist structure.

a reinforcing layer forming step (fourth step), forming a reinforcing layer on the conductive film by a plating treatment; and a master removing step (fifth step), removing the master mold, and forming a surface having a fineness based on the metal structure The mold of the bump pattern.

Here, the first to fifth steps are included, and the first to fifth steps are sequentially performed, but it is also included that other steps can be added between these steps. That is, it is clearly indicated that, for example, in the energization film forming step of the third step, a well-known pretreatment step for forming an energization film may be included before the energization film is applied.

According to the present invention, a metal-shaped surface to which a fine uneven structure based on a master mold is transferred can be obtained based on a method of lithography and electroplating, and a fine surface reflecting the mother mold is not formed on the back surface facing the forming surface. The embossed structure, that is, has a substantially smooth back surface.

In view of the above, a molding die having a molding surface on which a fine uneven structure based on a master mold is transferred is provided, and the molding surface is made of metal to ensure durability, and has a smooth back surface. Therefore, the planarity of the forming surface can be ensured.

An example of a preferred embodiment for carrying out the invention will be described with reference to the drawings, but the invention is not limited to the embodiments described below.

1A to 1E are cross-sectional views schematically illustrating the configuration of each step in the production of a molding die according to an embodiment of the present invention.

Here, FIG. 1A is a cross-sectional view obtained by the master mold forming step of the first step, and shows the mother mold 10A on which the conductive resist structure 11 based on the resist is formed on the conductive substrate 12. Further, Fig. 1B is a cross-sectional view obtained by the metal structure forming step of the second step, and the metal structure 13 having a thickness corresponding to the height of the resist structure 11 obtained by the master molding step is imparted thereto. The energization portion 12a of the resist structure 11 is not formed. In addition, FIG. 1C is a cross-sectional view obtained by the energization film forming step of the third step, covering the surfaces of the resist structure 11 and the metal structure 13 obtained by the first and second steps, thereby forming the dielectric film 14 . Further, Fig. 1D is a cross-sectional view obtained by the reinforcing layer forming step of the fourth step, and the reinforcing layer 15 is formed by electroplating on the dielectric film 14 obtained by the third step. Further, Fig. 1E is a cross-sectional view showing the molding die (main mold) of the present invention obtained by the master mold removing step of the fifth step, and after the reinforcing layer is formed by the fourth step, the energized substrate 12 as the master mold is removed. The resist structure 11 is obtained as a molding die having a fine concavo-convex pattern based on the metal structure 13 on the surface.

Hereinafter, the description will be sequentially made based on the first to third embodiments.

As shown in FIG. 1A, in the first step (master mold forming step) of forming the master mold 10A, the fine convex resist structure 11 is formed on the energized substrate 12 in accordance with the desired arrangement, and the substrate is energized. Above the 12, it is ensured that the upper space 13' of the resist structure 11 is not formed.

Here, the method of forming the resist structure 11 on the current-carrying substrate 12 is not particularly limited, and for example, a method based on ordinary photolithography can be employed. In the method based on such photolithography, for example, a step of imparting a resist layer, a pattern processing step, and a developing step are included. In the step of imparting a resist, a resist layer having a thickness corresponding to a desired unevenness is applied to the substrate. Further, in the patterning step and the developing step, the resist layer is removed by a mask or the like or by a suitable method, and a part of the resist layer is removed in accordance with the pattern. Thereby, the resist applied by a predetermined thickness is removed in accordance with the pattern, whereby the master 10A shown in FIG. 1A is formed, and the master 10A is obtained by applying the remaining resist structure 11 to the conductive substrate 12.

The resist material to be used is a master mold forming step (first step), a metal structure forming step (second step), an energized film forming step (third step), and a reinforcing layer forming step (fourth step). In each step, the material has a property of maintaining the morphology without deformation or the like, and has a property that can be removed in the final master mold removal step (the fifth step). The material is not particularly limited and can be widely used. . In addition, the width, height, pitch, and shape of the resist structure as the object may be appropriately selected.

As the resist material to be used, for example, a resist material which can react with active energy light such as X-ray, electron beam, laser light, or ultraviolet light can be cited.

For example, in the case of using ultraviolet light, a phenol resin, a dichromic resin, a polyvinyl alcohol cinnamate resin, an azide resin, an epoxy resin, or the like can be given.

In addition, it is also possible to illuminate the near-ultraviolet light of the i-light (365 nm) on the negative resist or the positive resist to form a contrast of dissolution/non-dissolution of the solvent corresponding to the two-dimensional pattern of the chrome cover, by solvent A method of obtaining a 3-dimensional structure like this.

The current-carrying substrate 12 of the present invention is a substrate having a portion (electroconducting portion 12a) having conductivity (electrical conductivity) on at least one surface, and the current-carrying portion 12a is a surface characteristic and a current level from which the resist material can form the master 10A. Selected from the substrate. Examples thereof include metals such as nickel, aluminum, copper, chromium, gold, and platinum, and alloys such as stainless steel, and nickel, aluminum, copper, chromium, and gold are deposited on the surface by vapor deposition, sputtering, or electroless plating. Glass, enamel, and resin made of white gold. The above-described methods for forming the resist structure 11 can be suitably selected.

Here, the surface characteristics to such an extent that the master mold 10A can be formed include appropriate adhesion properties determined by the characteristics against the resist material, peelability in the master mold removal step to be described later, and various resistances. As various kinds of resistance, for example, when the resist structure 11 is formed, when an alkaline aqueous solution is used as the developing liquid, nickel, stainless steel, nickel vapor-deposited glass, or the like having alkali resistance can be selected.

Further, the peelability includes a case where the metal structure 13 deposited by the metal structure forming step can be peeled off from the substrate 12 constituting one of the master molds. That is, the plating treatment exemplified as a preferred method in the metal structure forming step described later is generally used for coating a solid surface with a metal. Therefore, in the plating treatment, there is a case where the pre-treatment is performed, and the pre-treatment makes the adhesion between the solid surface of the metal coating object and the precipitated metal good.

On the other hand, in the present invention, since the metal deposited on the current-carrying substrate and the current-carrying substrate 12 are peeled off, it is not necessary to perform the process for improving the adhesion, or to limit the process to a minimum. Further, the current-carrying substrate can be selected from those having good peelability depending on the relationship with the deposited metal.

For example, there is always a thin, transparent and tightly adherent film on the surface of stainless steel. Moreover, even if the film is removed, it is immediately regenerated in other oxidized states exposed to the air. The presence of this film generally hinders the adhesion of "plating". This is because in the usual plating treatment, the plating treatment is performed immediately regardless of whether or not the film is removed, and it is necessary to pay attention to the film to be regenerated before the plating treatment. In the energized substrate 12 of the present invention, there is no need to be concerned with such an improvement in adhesion.

Next, the arrangement and size of the resist structure 11 can be appropriately determined depending on the resin molded article to be the object of interest. The third and fourth figures show the configuration of the pattern used in the embodiment for verifying the effects of the present invention to be described later. Here, Fig. 3 is a plan view showing the arrangement of the resist structures 11, and Fig. 4 is a cross-sectional view taken along line iv-iv' in Fig. 3.

In the figures, the symbol a indicates the height of the resist structure, the symbol b indicates the width of the resist structure, the symbol c indicates the length of the resist structure, and the symbol d indicates the distance between the resist structures.

Among them, in the present invention, when the height a of the resist structure is high, a remarkable effect can be obtained. In other words, when the height a of the resist structure is low, as described above, the mold is easily deformed by the unevenness on the back surface, and the problem of deterioration in formability is small. On the other hand, in the case where the height a of the resist structure is higher, the mold is deformed by the unevenness of the back surface, and the problem of deterioration in moldability is more remarkable. However, the method for producing a molding die according to the present invention (which can be produced) In the molding die having substantially no irregularities on the back surface, even if the height a of the resist structure is increased, since no irregularities are formed on the back surface, deformation of the mold does not occur.

The height a of the resist structure which causes such deformation is usually 10 μm or more, and in most cases, 20 μm or more. On the other hand, although the height a of the resist structure of the present invention has no upper limit, it is usually about 1000 μm or less. In the present invention, it is characterized in that the step of lithography is carried out in the manufacturing step of the forming mold, and one of the characteristics of the lithography is microfabrication. This is because the greater the height or spacing, the less obvious the features of the invention become. In order to clearly produce the characteristics of lithography, it is preferably 300 μm or less, and particularly preferably 200 μm or less.

Further, for the same reason, the width b and the pitch d are not particularly limited, but in general, the width is selected from the range of 0.5 μm to 500 μm, and the pitch is selected from the range of 1 μm to 1000 μm.

Next, as shown in FIG. 1B, in the second step (metal structure forming step), in the upper space 13' obtained by the first step (mother mold forming step), the deposition thickness is equivalent to a fine convex resistance. The metal structure 13 is formed by the metal of the height of the agent structure 11.

The precipitation of the metal is preferably a so-called electroforming method in which a metal structure corresponding to the resist structure 11 can be formed without electroless plating, but a metal is deposited by an electroplating method.

The metal structure 13 is formed by simply performing the surface side of the master 10A obtained in the first step by a usual electroplating method (so-called electroforming method). The convex resist structure 11 and the conductive portion 12a to which the convex resist structure 11 is not provided are exposed on the surface side of the master 10A obtained in the first step, but the exposed portion of the resist structure 11 ( Since the tip end surface 11a and the side surface 11b) have no electrification (conductivity), the metal is not deposited by electroforming, and only the metal is deposited in the current-carrying portion 12a. Thereby, if the usual electroplating is performed, the metal can be selectively deposited only in the upper space 13'. Further, by appropriately selecting the amount of energization, the metal structure 13 having a thickness corresponding to the height of the fine convex resist structure 11 can be formed. According to the usual electroplating, a thick film-like metal having a substantially uniform thickness can be deposited on the upper portion of the conducting portion 12a. Thereby, the surface of the deposited film (or the deposited film) is substantially parallel to the plane of the conductive portion 12a, and the metal structure 13 having a thickness corresponding to the height of the fine convex resist structure 11 can be formed.

Since the metal structure 13 serves as a pattern surface of the molding die, it can be suitably selected from materials suitable for the hardness of the surface of the mold and durability. In addition, the peeling property with the master mold 10A should be considered at the same time, as described above. Further, the stability of the electroplating bath, the plating conditions, and the like can be appropriately selected according to a usual method.

Examples of the material for forming the metal structure 13 include copper, iron, nickel, nickel phosphorus alloy, nickel manganese alloy, nickel cobalt alloy, nickel molybdenum alloy, nickel tungsten alloy, cobalt molybdenum alloy, and cobalt tungsten alloy. Wait.

In order to form the metal structure 13 by electroless plating, the electrically conductive substrate 12 having reducibility to the electroless plating solution can be used. Examples of such a current-carrying substrate 12 include a Group VIII metal such as iron, nickel, or platinum. These energized substrates 12 may be subjected to activation treatment or the like as needed within a range in which the structure of the resist structure 11 is not broken or damaged. These processes are, for example, active treatment of active energy light, plasma, etc., whereby the electroless plating treatment can be smoothly performed.

Next, as shown in FIG. 1C, in the third step (the energization film forming step), the energization film 14 is formed on the surface (tip surface 11a) of the resist structure 11 obtained in the first step. It is preferable that the conductive film 14 can be easily formed on the surface of the metal structure 13 obtained in the second step at the same time. Thereby, a plating layer as the reinforcing layer 15 can be provided to the front end surface 11a and the surface 13a of the metal structure 13.

The conductive film 14 of the present invention is not particularly limited as long as it can be in close contact with the resist material and can be energized, and examples thereof include nickel, aluminum, and copper by vapor deposition, sputtering, electroless plating, or the like. , film of chromium, gold, platinum, etc. It can be suitably selected according to the purpose, but it is preferably the same composition as the metal structure 13.

In addition, in the step of providing the conductive film 14 in the above, in general, the conductive film 14 which is not only in close contact with the metal structure 13 but also smooth as a whole can be provided.

Here, the film thickness of the current-carrying film 14 is not particularly limited, and if it is too thin, it is likely to cause an abnormality in electricity or film peeling, and if it is too thick, it takes a long time to produce. Further, in the energization film forming step, when the vapor deposition or sputtering treatment is performed, the temperature of the resist surface will rise. This is because when a thick film is formed by such treatment, the amount of heat accumulated in the surface of the resist increases, and the adhesion between the resist and the conductive film is improved, and the peeling of the resist material becomes difficult. From the above viewpoints, in the normal case, it is preferable that the film thickness of the dielectric film 14 is in the range of 25 nm to 500 nm.

Next, as shown in FIG. 1D, in the fourth step (reinforcing layer forming step), the reinforcing layer 15 is formed on the dielectric film 14 by a plating process. Thereby, a plating layer (reinforcing layer 15) having a flat back surface 15a can be obtained. Here, the back surface 15a of the present invention refers to the surface on the opposite side to the molding surface 10a of the molding die 10, and the air interface of the plating layer 15 is referred to as the back surface 15a.

This plating layer 15 can be substantially the same as the method of imparting the metal structure 13. That is, in consideration of the durability and the reinforcing property of the molding die 10, the hardness is more preferable than the metal structure 13, and the same as the metal structure 13, the shape can be appropriately selected depending on the purpose.

Next, as shown in FIG. 1E, in the fifth step (master mold removing step), the mother mold 10A is removed by an appropriate method, and the molding surface 10a having the fine uneven pattern based on the metal structure 13 is exposed to obtain electricity. The molding die 10 in which the back surface 15a of the film 14, the reinforcing layer 15, and the metal structure 13 is flat is flat.

When the conductive film 14 exposed on the molding surface 10a is not suitable as the surface material of the molding die 10, the exposed portion of the surface of the dielectric film 14 can be removed. In the case where the dielectric film 14 is removed, it is of course preferable to determine the height a of the resist structure 11 in consideration of the thickness of the current-carrying film.

(variation)

In the following, a modification of the preferred embodiment of the present invention will be described with reference to the drawings, and the same or equivalent components will be denoted by the same reference numerals, and the detailed description will be omitted.

In the first embodiment of the display embodiment, the convex resist structure 11 is formed in the central portion of the conductive substrate 12. However, the position of the resist structure 11 on the conductive substrate 12 is not limited.

For example, in the master 20A of the present modification, as shown in FIG. 9A, the resist structure 11' is formed along the side wall 12b except for the resist structure 11 located at the central portion of the conductive substrate 12. In the master mold 20A, the area of the distal end surface 11a' of the resist structure 11' is wider than the area of the distal end surface 11a of the resist structure 11 located at the center.

Hereinafter, the mold 20 shown in Fig. 9E can be obtained by the same procedure as in the embodiment. In the mold 20, the surface structure of the mother die 20A is reflected, and the metal structure 13 is not formed around the molding surface 10a and is not formed.

The surface roughness of the back surface 15a of the molding dies 10, 20 of the present invention obtained by the above steps, that is, the surface opposite to the molding surface 10a of the fine concavo-convex structure corresponding to the resist structure 11 is equivalent to electroplating. The surface roughness of the layer 15 has, for example, irregularities of 1 μm or less in the case of electroforming. This unevenness is not caused by the fine concavo-convex structure of the resist structure 11, but is caused by the electroforming method, and the unevenness of this degree does not cause molding failure, but it is not possible to use sandpaper or the like. There is a slight grinding of the degree of thermal elongation, but this is not meant to exclude the practice of the invention.

The mold thus obtained can be used as a mold for precision microfabrication technology. As such a precision microfabrication technique, for example, nanoimprint molding (hereinafter, simply referred to as imprint) may be mentioned. Here, the imprinting means a method of pressing a very fine unevenness formed on a molding surface of a mold against a resin applied to a substrate, and transferring the shape of the molding surface to the resin. In general, a polymer film of a thermoplastic resin such as polymethyl methacrylate on a substrate is pressed against a substrate by a molding die (mold) under a reduced pressure atmosphere, and the substrate is heated to heat. The plastic resin has a glass transition temperature or higher. After a certain period of time, the forming mold (mold) and the substrate were cooled to room temperature, and the forming mold was peeled off from the substrate. Thereby, a technique of a step of forming a fine uneven pattern on a polymer film is passed.

A treatment for improving mold release property may be performed on the surface of the mold as needed.

In addition, the molding die obtained by the above method is expected to be applied to various resin molded articles by resin molding, such as display members such as liquid crystals, recording media such as DVDs, mobile phone devices, and DNA. A molded article requiring a fine uneven structure centering on a micron-order or sub-micron-order such as a biochip such as a wafer.

(Example)

Next, an embodiment of the present invention will be described by way of specific examples. Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to the examples.

Further, the examples shown below are based on Figs. 1A to 1E and Figs. 3 and 4 without any limitation, and the comparative examples are based on Figs. 2A to 2E and Figs. 3 and 4. The figure is carried out.

Here, the height a, the width b, the length c, and the pitch d of the resist structures of the examples and the comparative examples were a = 20 μm, b = 20 μm, c = 80 μm, and d = 100 μm, respectively. Further, in the molding dies of the examples and the comparative examples, fine concavo-convex structures corresponding to the third and fourth figures were formed in a circle having a diameter of 16 mm.

When the fine concavo-convex structure of the mold was formed on the resin by the molding dies of the above examples and comparative examples, the molding was carried out using a nanoimprint molding apparatus manufactured by Jenoptik. A stainless steel of SUS304 having a thickness of 10 mm was used as a substrate (hereinafter referred to as a SUS substrate), and a molding die was attached to the SUS substrate with a double-sided tape, and the SUS substrate to which the molding die was attached was attached to the molding apparatus. Acrylic acid (polymethyl methacrylate) was heated and pressurized to obtain a resin fine concavo-convex structure. The heating was carried out at 125 ° C, the pressurization was carried out at 5 MPa, and the maximum holding pressure was maintained for 120 seconds. The moldability of 100 moldings was evaluated as an index of moldability.

The planarity of the molding dies of the examples and the comparative examples was measured by NH-3SP manufactured by Three Eagles.

[Example 1]

On the planar SUS substrate having a thickness of 1 mm, the resist structure 11 of the size shown in Figs. 3 and 4 was produced by photolithography using near-ultraviolet light, and 20 μm was deposited on the SUS substrate by Ni electroforming. Ni. Then, vacuum deposition of Ni was performed, and an electric current film was formed on the substrate formed in the second step, and Ni electroforming was further performed to deposit 500 μm of Ni.

After the resist is removed, the forming mold 10 is obtained. The surface of the forming mold is subjected to oxygen plasma treatment for forming.

[Comparative Example 1]

A molding die having irregularities of a fine structure on the back surface is produced by the manufacturing method shown in Figs. 2A to 2D. On the flat glass substrate having a thickness of 1 mm, the resist structure 31 having the size shown in Figs. 3 and 4 was produced by photolithography using near-ultraviolet light. Then, an energization film was formed by vacuum deposition of Ni, and Ni electroforming was performed to deposit 500 μm of Ni. After the resist is removed, the forming mold 40 is obtained. The surface of the forming mold is subjected to oxygen plasma treatment for forming.

[Comparative Example 2]

A molding die having a back surface polished to a smooth surface was produced by the manufacturing method shown in Figs. 2A to 2E. On the flat glass substrate having a thickness of 1 mm, the resist structure 31 having the size shown in Figs. 3 and 4 was produced by photolithography using near-ultraviolet light. Then, an energization film was formed by vacuum deposition of Ni, and Ni electroforming was performed to deposit 500 μm of Ni. After the resist was removed, the surface of the mold was coated with a protective film, and the unevenness of the back surface was polished with #80 and #400 sandpaper to obtain a flat molding die 50. Then, the protective film was peeled off, washed with a solvent, and then subjected to an oxygen plasma treatment to form.

In the molding die produced in Example 1 and Comparative Example 2, although the transfer marks corresponding to the unevenness on the back surface of the mold were not observed, in the molding die manufactured by Comparative Example 2, it was observed. A transfer mark corresponding to the unevenness of the back surface.

Fig. 5 is a view showing the planarity of a region in which the fine concavo-convex structure is formed in the molding die produced by the method of the first embodiment. The difference between the lowest part and the highest part (hereinafter, ΔH) is ΔH = 4 μm, and the flatness is good, and the mold is used for embossing. The filling property of the acrylic resin is uniform in the plane, and stable molding of 100 times of molding can be achieved.

Fig. 6 is a view showing the planarity of a region in which a fine concavo-convex structure is formed in a molding die produced by the method of Comparative Example 1. Where ΔH = 7 μm, the mold was used for embossing. Although the filling property to the outermost peripheral portion of the formation region of the fine concavo-convex structure is obtained, the filling becomes insufficient as the center of the region is formed, and the transfer rate of the fine concavo-convex structure is lowered at the center portion. Fig. 7 shows the planarity of the forming mold after the fifth forming. After the fifth molding, ΔH = 23 μm, and the molding die was largely deformed by the fifth molding, and the molding was not stopped.

In addition, Fig. 8 shows the planarity of the region in which the fine concavo-convex structure is formed in the molding die produced by the method of Comparative Example 2. Among them, ΔH = 47 μm, which is poor in planarity, and is formed by imprinting using this mold. Although the outermost peripheral portion of the formation region of the fine concavo-convex structure is formed with one portion of the upper surface of the structure, the entire upper surface is not formed, and the filling is insufficient, so that the transfer rate is further toward the center of the formation region of the fine concavo-convex structure. Lower, the height of the center is about 12μm.

As a result of changing the pressing force to 7.5 MPa, the transfer rate of the central portion of the formation region of the fine concavo-convex structure is improved, and one of the upper portions is formed, but in the vicinity of the outermost peripheral portion, acrylic acid is caused during demolding. The resin is deformed and it is impossible to form a uniform shape.

Further, the present invention is not limited to the above-described embodiments. Within the scope of the present invention, the elements of the above-described embodiments can be changed, added, and converted into contents that can be easily considered by those skilled in the art.

The present application claims priority based on the invention disclosed in Japanese Patent Application No. 2008-204372.

10. . . Mold

10A. . . Master model

11. . . Resistor structure

11'. . . Resistor structure

11a. . . Top surface

11a'. . . Top surface

11b. . . side

12. . . Powered substrate

12a. . . Power supply department

12b. . . Side wall

13. . . Metal structure

13'. . . Upper space

13a. . . surface

14. . . Power film

15. . . Reinforcing layer

15a. . . back

20. . . Mold

20A. . . Master model

31. . . Resistor structure

32. . . Substrate

33. . . Power film

34. . . Plating

34a. . . back

34b. . . Concave structure

40. . . Mold

50. . . Mold

a. . . Height of the resist structure

b. . . Width of the resist structure

c. . . Resistor structure length

d. . . Distance between resist structures

Fig. 1A is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to an embodiment and a first embodiment.

Fig. 1B is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to an embodiment and a first embodiment.

Fig. 1C is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to an embodiment and a first embodiment.

Fig. 1D is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to an embodiment and a first embodiment.

Fig. 1E is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to an embodiment and a first embodiment.

Fig. 2A is a cross-sectional view schematically illustrating a method of manufacturing a molding die of a conventional example or a comparative example.

Fig. 2B is a cross-sectional view schematically illustrating a method of manufacturing a molding die of a conventional example or a comparative example.

2C is a cross-sectional view schematically illustrating a method of manufacturing a molding die of a conventional example or a comparative example.

Fig. 2D is a cross-sectional view schematically illustrating a method of manufacturing a molding die of a conventional example or a comparative example.

Fig. 2E is a cross-sectional view schematically illustrating a method of manufacturing a molding die of a conventional example or a comparative example.

Fig. 3 is a plan view showing the configuration of a resist structure of the examples and the comparative examples.

Fig. 4 is a cross-sectional view showing the configuration of a resist structure of Examples and Comparative Examples.

Fig. 5 is a perspective view showing the planarity of a region of the fine concavo-convex structure of the molding die of the first embodiment.

Fig. 6 is a perspective view showing the planarity of a region of the fine concavo-convex structure of the molding die of Comparative Example 1.

Fig. 7 is a perspective view showing the planarity of a region of the fine concavo-convex structure of the molding die of Comparative Example 1.

Fig. 8 is a perspective view showing the planarity of a region of the fine concavo-convex structure of the molding die of Comparative Example 2.

Fig. 9A is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to a modification.

Fig. 9B is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to a modification.

Fig. 9C is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to a modification.

Fig. 9D is a cross-sectional view schematically showing a method of manufacturing a molding die according to a modification.

Fig. 9E is a cross-sectional view schematically illustrating a method of manufacturing a molding die according to a modification.

10A. . . Master model

11. . . Resistor structure

11a. . . Top surface

11b. . . side

12. . . Powered substrate

12a. . . Power supply department

13. . . Metal structure

13'. . . Upper space

13a. . . surface

14. . . Power film

15. . . Reinforcing layer

15a. . . back

Claims (4)

A manufacturing method of a molding die having a fine concavo-convex structure on a molding surface, and the manufacturing method includes the following steps: a master molding step (first step), using a current having a current-carrying portion on at least one surface of the substrate a substrate, a mother resist is formed by providing a fine convex resist structure based on a resist, and a metal structure forming step (second step), wherein a thickness of the conductive portion is equal to a height of the resist structure a metal structure for forming a metal structure; an energization film forming step (third step), forming an energization film on the surface of the resist structure; and a reinforcing layer forming step (fourth step) by electroplating treatment The reinforcing layer is formed thereon; and the master mold removing step (the fifth step) removes the master mold to form a mold having a fine uneven pattern on the surface based on the metal structure. The method for producing a molding die according to the first aspect of the invention, wherein the height of the resist structure is 10 μm or more. The method of manufacturing a molding die according to claim 1, wherein the plating treatment of the reinforcing layer forming step is electroforming. The method for producing a molding die according to the first aspect of the invention, wherein the energized film forming step is formed by a method selected from the group consisting of vapor deposition, sputtering, and electroless plating.