JPS6277492A - Manufacture of electroformed die - Google Patents

Abstract

PURPOSE:To prevent the stripping of a strippable layer in an electroforming stage and to facilitate handling by forming an Al2O3 layer by ion plating as the strippable layer formed on the patterned surface of a matrix. CONSTITUTION:A strippable layer 9 is formed on the patterned surface of a matrix 8 having a fine uneven pattern, an electrically conductive film 10 is formed on the the layer 9 and electroforming is carried out to obtain a plated layer 11 formed integrally with the film 10. The film 10 and the layer 11 are then stripped from the matrix 8 to obtain a stamper die 12. The strippable layer 9 is an Al2O3 layer formed by ion plating.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a method for manufacturing an electroforming mold used as a synthetic resin molding mold or the like.

(Prior Art) Conventionally, electroforming molds have been used as synthetic resin molding molds that require reproduction of precise patterns. For example, based on a single master on which a fine and precise uneven pattern such as a rainbow pattern is formed, a large number of electroforming molds (stamper molds) having patterns whose unevenness is opposite to the uneven pattern of the master are created. There are known means to obtain .

That is, after forming a conductive film on the patterned surface of the master (depending on the material of the master, a conductive film may be formed through a release layer), electroforming is performed, and the conductive film is integrally formed by electroforming. After removing the formed plating layer from the master to obtain a mask mold having a pattern with an uneven pattern opposite to that of the master, the mask mold is placed on the patterned surface of the mask mold through a release layer. In the same manner as in the formation of the mask mold, a plurality of mother molds having a pattern in which the uneven pattern of the mask mold is opposite to the uneven pattern (i.e., a pattern that matches the uneven state of the master) are obtained, and each mother mold is further formed. Then, by the same means, a plurality of stamper molds each having a pattern having an uneven state opposite to that of the mother mold (that is, a pattern matching the uneven state of the mask mold) are obtained.

In this case, in the relationship between the master and the mask mold, the master is the mother mold and the mask mold is the child mold. Similarly, the relationship between the master mold and the mother mold is such that the former is the mother mold and the latter is the child mold, and the same holds true for the relationship between the mother mold and the skumper mold.

(Problems to be Solved by the Invention) In the electroforming mold manufacturing method described above, the release layer is a chromate film formed on the surface of the matrix by immersing the matrix in sodium chromate, sodium sulfide solution, etc. or sulfide film.

However, such chemically formed films are easily contaminated with impurities and have problems with the insulation between the matrix and the conductive film formed thereon. In addition, the thickness of the film is unstable and requires skill to control.Furthermore, the film is extremely fragile, so care must be taken when washing with water after the film is formed. There was a problem that the workability was poor due to peeling during electroforming.

The present invention has been made in view of such problems, and an object of the present invention is to provide a means for forming a release layer that can easily form a release layer on a matrix, has excellent insulation properties, and is free from problems in terms of strength. With the goal.

(Means for Solving the Problems) The method for manufacturing an electroforming mold of the present invention, which was taken to achieve the above object, is characterized by the fact that the peeling layer is formed by ion plating. The point lies in the use of layers.

(Example) Hereinafter, the present invention will be described in detail with reference to an example in which a large number of Sumpah molds are manufactured from a single master disk on which a fine uneven pattern is formed.

The master disk used in this example has a rainbow pattern with a depth of 0.
．． A plastic film, glass plate, or a photoresist film coated on a glass original plate is coated with a concave-convex pattern in which six protrusions of about 1 μm are spaced at intervals of several μm, and the unexposed areas are irradiated with a precise line drawing using a laser beam. A non-conductive master disc such as a holographic master disc which has been removed to form a fine uneven pattern is used. It goes without saying that the pattern on the master disc may be formed by superimposing a suitable pattern on such a fine pattern by screen printing or the like.

First, as shown in FIG. 1, a conductive film 2 is formed on a master 1. The conductive film 2 is necessary for integrally forming a plating layer by electroforming in the next step, and is usually formed using Ni or Cu by vacuum evaporation, sputtering, ion plating evaporation, or the like. One formed by ion plating is preferable because it does not peel off during electroforming. The thickness of the conductive film 2 is usually 0.04 to 1 μm.

After the conductive film 2 is formed, it is immediately attached to an electrolytic plating jig and electroforming is started to form a plating r53 integrally with the conductive film 2 as shown in FIG. For electroforming, nickel plating or copper plating is applied depending on the material of the conductive film 2. The thickness of the plating layer 3 is such that it can sufficiently reinforce the conductive film 2 and can be handled mechanically, and a thickness of about 200 μm is sufficient. Of course, it may be made thicker than this. In order to obtain this level of plating thickness, in the case of nickel plating, 0.
35-3.5 hours at a current density of 5-5 A/dm2, 24-3.5 hours at a current density of 1-5 A/dm2 for copper plating
It takes 4.5 hours.

After electroforming is completed, the master 1 on which the conductive film 2 and the plating layer 3 are formed is removed from the jig, and after washing and drying, the electroformed plate on which the conductive film 2 and the plating rii3 are integrally formed is mechanically removed from the master 1. A mask mold 4 is obtained by peeling.

When the thickness of the mask mold 4 is about 200 μm, a glass plate with a thickness of about several mm may be bonded to the back surface of the mask mold 4 for reinforcement.

Further, when a holographic master is used as the master, the resist film adheres to the mask mold during peeling, so it is necessary to melt and remove the resist film with an organic solvent such as alcohol. Further, when a glass master is used, it is preferable to first provide a release layer, which will be described later, on the patterned surface of the master, and then form a conductive film. The release layer serves as a protective layer for the master.

Next, as shown in Figure 3, the patterned surface of the mask mold 4 is ion plated to cause 0 damage! After forming the peeled + IS layer 5 and forming a conductive film 6 thereon, a plating layer 7 is integrally formed on the conductive film 6 by electroforming. This conductive film 6
The electroformed plate composed of the plating layer 7 is peeled off from the interface of the conductive film 6 of the peeling layer 5 formed on the mask mold 4 to become the mother mold 8. The conductive film 6 and the metal layer 7 are formed by the same means as in the case of manufacturing the mask mold 4.

The thinner the peeling [5] is, the better in order to accurately copy the fine pattern of the mask mold 4 onto the mother mold B, but insulation and strength must be ensured. If the insulation is impaired due to the occurrence of pinholes or the incorporation of impurities, the mask mold 4 and the mother mold 8 will be partially fused together, which will not only make it difficult to separate, but also damage the patterned surface of the matas mold 4. That means doing so. In addition, if the strength is insufficient, handling becomes difficult and peeling occurs during a long electroforming process.

In the present invention, peeling ill N5 is aj2. O! Since the layer is formed by ion plating, 0.04
It is possible to easily form a thin film with a density on the order of μm and excellent strength, and this thin film has excellent insulation properties due to its high purity, and is suitable as a release layer.

Note that an upper limit of the thickness of the release layer is 0.2 μm.

After the peeling layer 5 is aluminum ion plated,
Wi, elemental gas is introduced, and the aluminum layer is oxidized by oxygen discharge to obtain an AR, ot layer.

Furthermore, in aluminum ion plating, oxygen gas may be introduced from the beginning, and aluminum may be vapor-deposited in oxygen discharge to form the vapor-deposited film as the Aρi01 layer.

When performing an oxidation treatment after forming an aluminum layer, it is helpful to protect the pattern surface if the aluminum layer is left in contact with the pattern surface without oxidizing the entire aluminum layer. That is, when the mother mold 8 is peeled off from the mask mold 4, the peeling layer may partially adhere to the mother mold 8 side and the patterned surface of the mask mold 4 may be damaged. If the surface is coated, damage will not extend to the pattern surface. A large number of mother molds 8 from the mask mold 4
Considering that the mask mold 4 is manufactured, it is important that the pattern of the mask mold 4 is not damaged. The release layer of such a two-layer structure is
It is also possible to introduce oxygen gas during the vapor deposition of aluminum ion plating and convert it into aluminum oxide during evaporation of aluminum, thereby obtaining aluminum AρaO*Iil.

When manufacturing a large number of mother molds 8 from the mask mold 4, it is better to completely remove the release layer 5 formed on the patterned surface of the mask mold 4 each time and form a new release layer again. Electroforming can be performed faithfully to the mask mold 4. This is because, as described above, when the mother mold 8 is peeled off from the mask mold 4, the peeled part 5 formed on the mask mold 4 may be damaged.

As shown in FIG. 4, a release layer 9 is formed on the patterned surface of the mother mold 8 obtained as described above, and then a conductive film 10 is formed and electroformed to form an integral part of the conductive film 10. 1ill of plating is obtained. Then, as shown in FIG. 5, the conductive film 10 and the plating N11 are peeled off from the mother mold 8.
Stamper mold 1 having the same uneven pattern as mask mold 4
Get 2. In this case, the stripping M1i9, the conductive film 10, and the plating 1ill are formed as described above. Also, regarding the method of obtaining a large number of stamper molds 12, a large number of mother molds 8
The same is true for obtaining .

The surface of the stamper mold 12 opposite to the pattern is flat-face polished to eliminate variations in thickness during plating, cut to an appropriate size, and mounted in a resin molding mold.

In this way, a mask mold 4 and a mother mold 8 are created from a single master 1, and a number of stamper molds 12 can be manufactured by repeatedly electroforming each of them.

Next, a specific example will be described in which a large number of stamper molds are obtained using a PET (polyethylene terephthalate) film on which a rainbow pattern is formed as a master.

(11 Convex portion with a height of 0.1 μm (pinch of the convex portion 1 to 1.
8 μm), with a rainbow pattern formed by
The μ-box PET film was cut into 150×150 tm pieces and washed with an organic solvent. Thereafter, marks, letters, figures, etc. were printed on the patterned surface of the PET film by screen printing and dried.

(2) Next, a conductive film of nickel or copper was formed on the patterned surface of the PET film by high frequency excited ion plating.

・Ion plating condition achieved vacuum degree 5 X 10-' Torr Argon pressure 3 X 10-' Torr High frequency power 1
00W Film thickness 0.044m 0.06μm O
, 1/jm Evaporation method Nickel Electron beam evaporation copper Resistance heating method (3) Immediately after the conductive film was formed, it was attached to an electrolytic jig and electroforming was started using nickel plating or copper plating.

(4) Electroforming was completed when the thickness of the plating layer reached 200 μm, and it was removed from the jig, washed with water, dried, and then only the electroformed plate was peeled off from the PET film with tweezers to obtain a mask mold.

(5) After adhering and reinforcing a glass plate with a thickness of 2 cranes to the back of the mask mold using epoxy adhesive, a 0.1 μm aluminum layer is formed on the patterned surface of the mask mold by ion plating, and then Oxygen gas was introduced into the ion plating apparatus, and the aluminum surface was oxidized by oxygen discharge to form a release layer. Ion plating conditions etc. are as follows.

・Achieved vacuum level for aluminum ion plating 5 X 10-5 Torr Argon pressure during bombardment 5 X 10-' Torr Argon pressure during evaporation 3 X 10-' Torr High frequency power 100 W Bombardment time 1O minute evaporation method Resistance heating method/Oxidation Processing conditions Oxygen pressure 5 x 10-'Torr
High frequency power 100W Oxidation time
After forming the release layer for 20 minutes (6), a conductive film was deposited thereon by ion plating. The ion plating conditions are the same as in (2).

(7) Immediately after forming the conductive film, it was attached to a plating jig and electroforming was performed until the plating layer reached 200 μm.

(8) After electroforming, it was removed from the jig, washed with water, dried, and then the plating W1 (electroformed plate) integrally formed on the conductive film was peeled off from the mask mold using tweezers. At this time, the peeling layer remained completely on the mask mold side, and only the electroformed plate was peeled off, yielding a mother mold.

(9) Using the mother mold as the mother mold, steps (5) to (8) above were performed in the same manner to obtain a stamper mold.

QO) When obtaining a stamper mold from the same mother mold again, remove the peeling layer remaining on the mother mold by 20% each time.
Dissolve and remove with sodium hydroxide aqueous solution to create a new peel 1i
! ttFi was formed and steps (6) to (8) were performed.

As described above, a large number of stamper molds were obtained from a PET film master on which a single rainbow pattern was formed, but since the release layer was of extremely high quality, the pattern of the matrix was not damaged (
, all stamper molds formed extremely clear uneven patterns.

(Effects of the Invention) As explained above, according to the present invention, A Qz Ch N formed by ion plating is used for the release layer formed on the patterned surface of the matrix, so a thin film that is dense and has excellent strength can be obtained. can be easily formed, and it does not peel off during the electroforming process after Wi, making it easy to handle. In addition, high purity A9. Since the tCh layer can be easily formed, it has excellent insulation even if it is a thin film, the patterned surface of the master mold is not damaged during the electroforming process, and the reproducibility of the child mold is excellent.

As described above, the electroforming mold manufacturing method of the present invention can easily form a release layer with excellent strength and insulation properties, and has great industrial utility value.

[Brief explanation of drawings]

Figures 1 to 5 are explanatory diagrams of the manufacturing process of the example. Figure 1 is a cross-sectional diagram showing a state in which a conductive film is formed on a master, and Figure 2 is a diagram showing a state in which a mask mold is formed. FIG. 3 is an explanatory cross-sectional view showing the state of formation of the mother mold, FIG. 4 is an explanatory cross-sectional view showing the state of formation of the stamper mold, and FIG. 5 is a cross-sectional view of the standby mold. 1... Master disc, 2,6.10... Conductive film, 3,7.1
1... Plating layer, 4... Mask mold, 5.9...
Peeling layer, 8... Mother mold, 12... Standby mold. Patent applicant Toyokuni Jushi Kogyo Co., Ltd. Figure 7 Figure 3 Figure 2 Figure 4

Claims (1)

[Claims] 1. Form a release layer on the patterned surface of the master mold on which a fine uneven pattern is formed, form a conductive film on the release layer, and then form a plating layer on the conductive film by electroforming. , a method for manufacturing an electroforming mold in which a plating layer integrated with the conductive film is removed from the mother mold to obtain a child mold having a pattern having an uneven state opposite to that of the mother mold, wherein ion plating is used as the peeling layer. A method for manufacturing an electroforming mold, characterized by using an Al_2O_3 layer formed by.