JPH11172487A - Production of fine electroformed parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing fine electroformed parts capable of producing fine parts for which the external shapes, characteristics and accuracy obtainable heretofore only by the electroless plating method are required by an electroforming method. SOLUTION: In the case the fine electroformed parts are produced by patterning opaque conductive films 50 on a transparent substrate, patterning a photosensitive insoluble material 22 applied thereon by exposure from the transparent substrate 30 side and using such material as an electroforming mold, the process has a stroke for forming the opaque film consisting of fine parts forming regions 501 where the fine parts are formed by electroforming on the transparent substrate, electrode regions 502 for taking out of the electrodes at the time of the electroforming and wiring regions 503 for electrical connection of the fine parts forming regions 501 and the electrode regions 502 to each other. In addition, the width of the wiring regions 503 is set at a size in a range from 1/60 to 1/6 the thickness of the photosensitive insoluble material 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fine component formed by an electroforming method.

[0002]

2. Description of the Related Art In recent years, in the field of micromachines, there has been an increasing demand for fine parts having fine and complicated shapes.
In such a situation, many methods for manufacturing a fine component have been devised. Among them, the manufacturing method disclosed in Japanese Patent Application No. 8-141841 is a manufacturing method in which a master is formed by a photolithography method, and a fine part is formed by a plating method using the master. This is one of the effective methods as a method for manufacturing a fine component because it can be formed by using the method described above.

[0003] Hereinafter, a method for manufacturing a micropart using conventional photolithography and plating will be described.

FIG. 3 is a view showing a conventional method of manufacturing a fine component using a photolithography method and a plating method.
First, an opaque film 40 for blocking light is formed on a transparent substrate 30 having a light-transmitting property in a planar shape of a fine component (FIG. 3).
(A)).

Next, after coating the photosensitive insoluble material layer 20 on the opaque film 40, exposure is performed through the transparent substrate 30 (FIG. 3B). At this time, the opaque film 40 existing between the transparent substrate 30 and the photosensitive insoluble material layer 20 causes
In the photosensitive insoluble material layer 20, only a portion other than the planar shape of the fine component is exposed. Such an exposure method of exposing from the transparent substrate 30 side is generally called a back exposure method.

Thereafter, by developing the photosensitive insoluble material layer 20, the unexposed portion is dissolved and patterned as shown in FIG. 3 (c). In this way, a master including the photosensitive insoluble material layer 20, the opaque film 40, and the transparent substrate 30 is completed. Finally, a plating layer 10 is formed on the opaque film 40 by a plating method, and finally a fine component made of the plating layer 10 is formed (FIG. 3D). Thereafter, the original photosensitive insoluble material layer 20, the opaque film 40, and the transparent substrate 30 are removed from the plating layer 10, and the plating layer 1 is removed.
Thus, a fine part made of zero is completed.

[0007]

SUMMARY OF THE INVENTION In a manufacturing method using the photolithography method and the plating method as described above,
It is effective to use the electroforming method as the plating method because the plating rate is high and the plating thickness can be increased. However, since the electroforming method is a kind of the electrolytic plating method, it is necessary to take out the electrodes.

FIG. 4 is a view showing an example of forming a fine gear by the above method. An opaque film 41 patterned in a plane shape of a gear is formed on a transparent substrate 30. On the opaque film 41, a plating layer 11 serving as a fine gear is formed.
However, the photosensitive insoluble material layer 21 is formed on the transparent substrate 30 without the opaque film 41. In the case of a component requiring a fine shape and precision in the external shape such as a fine gear, the electrode cannot be taken out as is clear from FIG. Therefore, conventionally, there has been no other method but to form a fine gear, which is a fine part, using an electroless plating method. In the case of the electroless plating method, productivity is poor due to a low plating speed,
It is not suitable for forming thick fine parts.

Therefore, the manufacturing method of the present invention aims at improving the productivity by forming a fine component, which could only be formed by the electroless plating method in the past, by the electroforming method.

[0010]

In order to solve the above-mentioned problems, a method of manufacturing a micro electroformed component according to the present invention is to provide a method for manufacturing a fine electroformed part on a transparent substrate on which an opaque film having a predetermined shape is formed. Next, a photosensitive insoluble material is formed into a film, and the photosensitive insoluble material is patterned by exposing and developing the photosensitive insoluble material from the transparent substrate side through the opaque film, and forming a fine component on the opaque film using an electroforming method. In the method for manufacturing a fine electroformed component, a fine component forming region in which a fine component is electroformed on the transparent substrate, an electrode region for taking out an electrode during electroforming, and a space between the fine component forming region and the electrode region A step of forming an opaque film including a wiring region for electrical connection, and wherein the width of the wiring region is set to a size in the range of 1/60 to 1/6 of the thickness of the photosensitive insoluble material. Specially To.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an outline of a method for manufacturing a fine electroformed part according to the present invention will be described. FIG. 1 is a schematic view of a method for producing a fine electroformed part according to the present invention. FIG. 1 shows an example of the case of manufacturing a fine electroformed part having a hexagonal shape.

In FIG. 1, an opaque conductive film 50 is patterned on a transparent substrate 30 into a desired shape.
The opaque conductive film 50 is composed of the following three regions. Fine part forming region 50 in which fine parts are formed by electroforming.
1 and an electrode region 502 to be an electrode extraction portion during electroforming.
And a wiring region 503 having a small line width for electrically connecting the fine component forming region 501 and the electrode region 502.

The photosensitive insoluble material layer 22 formed on the transparent substrate 30 and the opaque conductive film 50 is exposed from the transparent substrate 30 side through the opaque conductive film 50 so that the opaque conductive film 50 is exposed. Only the non-existing portions are exposed.

Usually, development is performed after this. In the present embodiment, the thickness of the photosensitive insoluble material layer 22 is set to 100%.
By setting the line width of the wiring region 503 of the opaque conductive film 50 to 10 μm, the photosensitive insoluble material only on the fine component forming region 501 and the electrode region 502 is reduced as shown in FIG. It could be developed.

Thereafter, the electrode region 502 is connected to an external power source and electroforming is performed to form the fine component forming region 50.
A microelectroformed part having a hexagonal shape is formed on 1.

Hereinafter, this embodiment will be described in detail. The transparent substrate 30 is made of a glass substrate. First, an opaque conductive film 50 made of copper (Cu) is formed on the transparent substrate 30 to a thickness of about 0.2 μm by a sputtering method.
After that, the opaque conductive film 50 was patterned by a wet etching method. As described above, the line width of the wiring region 503 was formed to be about 10 μm by this patterning. Note that the fine component region 501 and the electrode region 502 are formed in a size enough to be sufficiently developed.

Next, the opaque conductive film 50 on the transparent substrate 30
The photosensitive insoluble material layer 22 is formed on one surface where
Was formed by spin coating. The photosensitive insoluble material layer 22 has a resist (trade name: THB) manufactured by Nippon Synthetic Rubber Co., Ltd.
-30) was used. This resist is a resist that can be applied to a thickness of about 50 μm by spin coating at 1000 rpm for 10 seconds. In the present embodiment, the coating was performed twice under the above conditions, and the photosensitive insoluble material layer 22 was able to have a thickness of 100 μm.

Further, the photosensitive insoluble material layer 22 applied on the entire surface of the transparent substrate 30 was exposed from the transparent substrate 30 side through the opaque conductive film 50 at an exposure amount of 600 mJ / cm 2.

Thereafter, development is performed for about 5 minutes using a dedicated developing solution, so that the fine component region 5 shown in FIG.
01 and the electrode region 502 could be developed.

Thereafter, wiring was performed from the electrode region 502 to an external power supply, and a Ni (Ni) electroformed component was formed on the fine component region 501 by a nickel (Ni) electroforming method. The thickness of the Ni electroformed part formed in the present embodiment was 60 μm.

Finally, it is necessary to separate the fine electroformed part made of Ni from the transparent substrate.
Separation was performed by dissolving the opaque conductive film 50 made of u by an etching method. In this way, a hexagonal fine electroformed part almost as designed could be manufactured.

In the present embodiment, the electroforming time required to form a micro electroformed part having a thickness of 60 μm was 3 hours. This is about one-fourth of the time required for plating when microparts of the same size are formed by electroless plating.
This also shows that the productivity is improved by the production method of the present invention.

Next, the line width of the wiring region of the opaque conductive film will be described. According to the results obtained by experiments by the present inventors, it has been clarified that the development state is different by changing the ratio of the line width b of the opaque conductive film to the thickness t of the photosensitive insoluble material layer. FIG. 2 is a diagram showing a difference in the development state when the ratio of the line width b of the opaque conductive film to the thickness t of the photosensitive insoluble material layer is changed.

FIG. 2A shows the ratio of the line width of the opaque conductive film 50a to the thickness of the photosensitive insoluble material layer 22a in b / t.
= Development state when = 1/2. The wall surface of the developed photosensitive insoluble material layer 22 a stands up substantially perpendicularly to the plane of the transparent substrate 30. In the case of such a cross-sectional shape, the electroforming solution can easily enter the developed portion during the electroforming, so that stable electroforming growth is performed.

FIG. 2B shows the ratio of the line width of the opaque conductive film 50b to the thickness of the photosensitive insoluble material layer 22b in b / t.
= 1/5. In this case, the width of the unexposed portion (that is, the portion to be developed) is narrow, so that the development tends to be insufficient. As a result, the development of the photosensitive insoluble material layer 22b is less advanced than that in FIG. The reason why the inversely tapered shape occurs near the opaque conductive film 50b is that light diffraction occurs at the edge of the opaque conductive film 50b during exposure, and the effect is clearly apparent due to insufficient development. However, the opaque conductive film 50b
The upper photosensitive insoluble material layer 22b is sufficiently developed,
In this state, electroforming is performed on the opaque conductive film 22b.

FIG. 2C shows the ratio of the line width of the opaque conductive film 50c to the thickness of the photosensitive insoluble material layer 22c in b / t.
= 1/6 in a developed state. In this case, FIG.
Since the development is further insufficient compared with (b), the development is slightly performed near the surface of the photosensitive insoluble material layer 22c, but the development does not progress to the vicinity of the opaque conductive film 50c. In this case, even if electroforming is performed, electroforming does not occur on the opaque conductive film 50c.

FIG. 2D shows the ratio of the line width of the opaque conductive film 50d to the thickness of the photosensitive insoluble material layer 22d in b / t.
= 1/10 is a developed state. In this case, even if the photosensitive insoluble material layer 22d is exposed from the transparent substrate 30 side, the entire surface is exposed near the surface of the photosensitive insoluble material layer 22d due to the light scattering phenomenon. As a result, little development occurs.

From the above results, it can be understood that electroforming is not performed on the wiring region by setting the line width of the wiring region of the opaque conductive layer to 1/6 or less of the thickness of the photosensitive insoluble material layer.

On the other hand, it is not always better to reduce the width of the wiring region. In order to achieve the purpose of flowing a current serving as a wiring region, a sufficient width for the current to flow is required. According to our consideration, it was concluded that electroforming can be performed if the width of the wiring region is 5 μm or more.

On the other hand, regarding the thickness of the photosensitive insoluble material layer, it is desirable that the thickness be less than 300 μm in order to perform fine and accurate patterning by one exposure, I have found it.

The above limitation of the thickness of the photosensitive insoluble material layer (3)
It was found that the line width of the wiring region of the opaque conductive layer had to be at least 1/60 of the thickness of the photosensitive insoluble material layer due to the limitation of the width of the wiring region (at least 5 μm width). .

As described above, based on the results of the experiments, the present inventors, in the method of manufacturing a micro electroformed component of the present invention, the line width of the wiring region is 1/60 or more 1 / th of the thickness of the photosensitive insoluble material layer.
It has been found that it is important to make it 6 or less.

In the above embodiment, the case where one wiring region is provided for one fine component formation region has been described. However, if the line width condition of the wiring region is satisfied,
A plurality of wiring regions may be connected to one fine component formation region. By uniformly arranging the plurality of wiring regions, the current density can be made uniform at the time of electroforming, so that the electroforming growth can be progressed stably.

[0034]

As described above, according to the method of manufacturing a fine electroformed part of the present invention, the electroforming (electrolytic plating) is not performed by the conventional manufacturing method using the photolithography method and the plating method.
Fine parts, such as fine gear parts, which could not be formed and whose characteristics and accuracy are required in the outer shape can be formed by electroforming. Therefore, the plating speed is high, and it is possible to cope with a component having a large plating thickness, and productivity is remarkably improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a method for manufacturing a micro electroformed part according to the present invention.

FIG. 2 is a diagram showing a difference in a development state when a ratio of a line width b of an opaque conductive film to a thickness of a photosensitive insoluble material layer is changed.

FIG. 3 is a view showing a conventional method of manufacturing a fine component using a photolithography method and an electroforming method.

FIG. 4 is a view schematically showing a method for manufacturing a fine gear by a conventional method.

[Explanation of symbols]

 Reference Signs List 10 plating layer 11 plating layer 20 photosensitive insoluble material layer 21 photosensitive insoluble material layer 22 photosensitive insoluble material layer 22a photosensitive insoluble material layer 22b photosensitive insoluble material layer 22c photosensitive insoluble material layer 22d photosensitive insoluble material layer 30 transparent substrate 40 opaque film 41 opaque film Reference Signs List 50 opaque conductive film 50a opaque conductive film 50b opaque conductive film 50c opaque conductive film 50d opaque conductive film 501 micro component forming region 502 electrode region 503 wiring region

Claims (1)

[Claims] 1. A photosensitive insoluble material is formed on a transparent substrate on which an opaque film having a predetermined shape and having conductivity is formed, and the photosensitive insoluble material is applied from the transparent substrate side through the opaque film. A fine component formed on the opaque film by electroforming using an electroforming method, wherein the fine component is electroformed on the transparent substrate. A step of forming an opaque film including a region, an electrode region for taking out an electrode at the time of electroforming, and a wiring region for making an electrical connection between the fine component forming region and the electrode region; A method for manufacturing a fine electroformed part, wherein the width of the region is set to a size in the range of 1/60 to 1/6 of the thickness of the photosensitive insoluble material.