JPH1180997A - Formation of insulating part and conductive molding having insulating part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form insulating parts of various kinds of patterns of a uniform thickness having an excellent adhesion property regardless of shapes, sizes, etc., by sticking a photoresist by electrodeposition to the surface of a conductive molding, exposing this resist to cure the resist. SOLUTION: The photoresist 2 is stuck by electrodeposition to the entire surface of a metallic sheet 1, for example, a copper sheet, which is the conductive molding. A mask 3 having the patterns of non-photosensitive parts is brought near to the desired part on the formed photoresist 2 and is exposed by a light source 4. The photoresist 2 of the parts not subjected to light shielding by the mask 3 is cured by this treatment. After the mask 3 is removed, the photoresist 2 of the uncured parts (unexposed parts) is removed by development to allow only the cured photoresist 2 of the desired patterns to remain. The remaining parts are formed as the insulating parts. The photoresist 2 forming the insulating parts is subjected to a heat treatment in order to improve the acid resistance and wear resistance thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating material capable of forming an insulating layer having a uniform thickness on a desired portion of the surface of a molded article having conductivity regardless of the shape and size of an object to be processed. The present invention relates to a method for forming a part. Further, the present invention relates to a conductive molded article having an insulating portion obtained by applying the method.

[0002]

2. Description of the Related Art When an insulating layer is formed between metal conductors, a method is generally employed in which an insulator is sandwiched between conductors, or an insulating material is adhered to or applied to one or both contact surfaces. Have been. These methods are easy to apply, for example, in the case of a flat conductor, but the operation is very complicated if a complete insulating layer is to be formed on a conductor having a complicated shape or a minute conductor. It is not economical, and it cannot be said that it is industrial. In the case of a three-dimensional object or a conductor having minute irregularities on the surface, it is difficult to form an insulating layer having a uniform thickness. It may be.

As a method of forming an insulating layer on a conductor having such a complicated shape, for example, in the case of a center conductor of a non-reciprocal circuit device used as an isolator or a circulator in mobile communication such as a car phone or a mobile phone. Is
The above-mentioned problem will appear more remarkably. Various structures of the non-reciprocal circuit device are known. The structure described in JP-A-6-196907 will be described as an example.

In this non-reciprocal circuit device, as shown in FIG. 8, a ground plate 101 is soldered on a metal lower case 100, a dielectric substrate 102 is soldered thereon, and a central hole of the dielectric substrate 102 is formed. A ferrite core 103, which is a ferrimagnetic material, and a center conductor 104 are inserted and soldered into 102a. And the ferrite core 103
In order to apply a direct current magnetic field to the vertical direction, a magnet 105 is provided, and a metal upper case 106 is further mounted.

Among them, the central hole 10 of the dielectric substrate 102
2a and the center conductor 1
04 has a structure as shown in FIG. 9 in more detail. That is, the center conductor 104 is spaced apart from the central circular shield plate 104a by 120 degrees.
4a and a conductor piece 104b projecting radially from the conductor piece 104b. Then, the ferrite core 103 is placed on the shield plate 104a, and each conductor piece 104b is bent from the boundary with the shield plate 104a, passes through the peripheral surface of the ferrite core 103, and is placed on the upper surface of the ferrite core 103. It is bent so as to intersect and overlap at each degree. Also, a sheet-like insulator 107 made of polyimide or the like is interposed between the conductor pieces 104b so that the conductor pieces 104b bent on the upper surface of the ferrite core 103 are insulated from each other. .

[0006]

In order to bend the conductor piece of the center conductor with a ferrimagnetic material and to overlap the conductor piece, as described above, the insulator is attached or sandwiched between the conductor pieces. Must. Therefore, it is necessary to prepare insulators in accordance with the number of conductor pieces, and it is necessary to attach or sandwich the insulators according to the number, that is, the number of times of folding, and the folding of the conductor pieces is required. This requires a lot of work and time. Further, since the sheet-shaped insulator as shown in FIG. 9 has the same size as the shield plate, the insulating portion may be provided only in a portion where the conductor pieces overlap each other. There will be extra parts. For this reason, cost is also wasted. On the other hand, when an insulator having a size corresponding to only the overlapping portion of the conductor pieces is provided, positioning when attaching or sandwiching is very troublesome. Further, the sheet-shaped insulator generally has a problem that it is easily shifted or peeled off.

Therefore, the present invention has an insulating portion of various patterns including a fine pattern having excellent adhesion and a uniform thickness regardless of the shape and size of the conductor to be processed. It is an object of the present invention to provide a method for forming an insulating portion from which a conductive molded body can be obtained. Also, the present invention
It is another object to provide a conductive molded article having an insulating portion obtained by applying the above method.

[0008]

Means for Solving the Problems The present invention comprises, as means for solving the problems, a step of attaching a photoresist to the surface of a molded article having conductivity by electrodeposition, and a step of exposing and curing the photoresist. A method for forming an insulating portion is provided. Further, the present invention provides, as means for solving the problems, a step of attaching a photoresist to the surface of a molded article having conductivity by electrodeposition, a step of exposing and curing the photoresist through a mask of a desired pattern, and an unnecessary step. A method for forming an insulating portion, comprising a step of removing a portion of photoresist.

Further, the present invention provides a method for forming an insulating portion, further comprising a step of heating the remaining photoresist in each of the above methods.

The present invention also provides, as another means for solving the problems, an insulating portion, wherein an insulating portion made of a photoresist having a desired pattern is formed on a surface of a molded body having conductivity. Provided is a conductive molded article having the same.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings. FIG. 1 is a process diagram for explaining a basic embodiment of a method for forming an insulating portion according to the present invention, in which (a) is a schematic conceptual diagram for explaining electrodeposition, and (b) to (b). d) is a cross-sectional view for explaining each step.

First, in a first step, as shown in FIG. 1A, a photoresist is deposited on the entire surface of a metal plate (eg, a copper plate) 1 as a conductive molded body by electrodeposition. By this electrodeposition, as shown in FIG. 1B, the photoresist 2 can be attached to the entire surface of the metal plate 1 as a conductive molded body. The conductive molded body used in the present invention has a composition, a shape, a size, and the like according to the use and the like, and is not particularly limited. Further, the photoresist used in the present invention may be either a negative type or a positive type. Hereinafter, the case where a negative type photoresist is used will be described. As the electrodeposition in the first step, either a cationic electrodeposition method or an anion electrodeposition method can be applied.

Next, in a second step, as shown in FIG. 1C, a mask 3 having a pattern of a non-photosensitive portion is formed on a desired portion on the photoresist 2 formed on the surface of the metal plate 1. It comes close and is exposed by the light source 4. By this process, the photoresist 2 in a portion not shielded by the mask 3 is hardened.

Next, in a third step, as shown in FIG. 1D, after the mask 3 is removed, an unnecessary portion, in this case, an uncured portion (unexposed portion) of the photoresist 2 is developed. After removal, only the hardened photoresist 2 having the desired pattern is left. The cured photoresist 2 becomes an insulating portion.

Thereafter, if necessary, a heat treatment can be performed to improve the acid resistance and the wear resistance of the cured photoresist 2 forming the insulating portion. The conditions for this heat treatment vary depending on the type of photoresist and the like.
It can be performed by heating at 0 ° C. for about 2 to 5 minutes.

In this way, it is possible to obtain the conductive molded body (metal plate) 1 having the uniform thickness and having the insulating portion 2 free of defective portions such as pinholes. According to such a method for forming an insulating portion, an insulating portion having a desired pattern can be formed on a desired portion of the molded body regardless of the shape or size of the conductive molded body to be processed. . Therefore, if the method for forming an insulating portion of the present invention is applied,
For example, a continuity checker 50 for a semiconductor as shown in FIG.
As described above, only the portion 52 excluding the very small needle 51 (about 200 μm in width and about 150 μm in thickness) can be insulated. When conducting continuity of a plurality of pins (not shown) provided on a semiconductor, the plurality of semiconductor continuity checkers 50 are arranged adjacent to each other. Since the portions 52 except the needles 51 where the insulating portions are formed are in contact with each other, a short circuit can be prevented.

Next, formation of an insulating portion on a center conductor for a non-reciprocal circuit device as an example of an object having a more complicated shape,
This will be described with reference to FIGS. 3 to 6 are process diagrams for explaining a more complicated embodiment of the method for forming an insulating portion according to the present invention. 3 and 5 are front views for each step, and FIGS. 4 and 6 are cross-sectional views of each step corresponding to FIGS. 3 and 5, respectively. FIG. 5A is a conceptual diagram for explaining electrodeposition.

First, in a first step, as shown in FIGS. 3A and 4A, a photoresist 1 is formed on both surfaces of a metal plate 11 as an original plate by the electrodeposition method shown in FIG.
2 is deposited. Since the photoresist 12 does not directly form an insulating portion, the photoresist 12 may be attached by another method such as a method of attaching a dry film resist, a method of dipping in a liquid resist, and then pulling up.

Next, in the second step, as shown in FIGS. 3 (b) and 4 (b), a desired central conductor (product part 21) is formed into a desired shape as shown in FIG. 5 (e). A mask 13 having a pattern 31 along the periphery, that is, a pattern 31 of a non-photosensitive portion having a periphery 31a of a portion corresponding to a circular shield plate, a periphery 31b of a portion corresponding to each conductor piece, and a corresponding portion 31c of a punched portion of each conductor piece. The portion excluding the pattern 31 of the photosensitive portion is transparent) is brought close to the surface of each photoresist 12 attached to both surfaces of the metal plate 11. In the pattern 31, a part 31d of a periphery 31b of each conductor piece corresponding part is formed from a bridge connection part 23 connected to an unnecessary part 22 which does not become the product part 21 of the original metal plate 11 from the viewpoint of workability. (See FIG. 3 (e)).
It is a photosensitive section. Then, the mask 13 is exposed by the light source 14 in a state of being close to the mask 13.

Next, in a third step, as shown in FIGS. 3C and 4C, the photoresist 12 which has been developed and is not cured according to the pattern 31 is removed, and the photoresist along the pattern 31 is removed. The part 28 is formed.

Next, in a fourth step, as shown in FIG. 3D and FIG. 4D, a portion of the metal plate 11 corresponding to the resist removing portion 28 is through-etched using an etching solution, A through portion 25 is formed.

Next, in a fifth step, as shown in FIGS. 3E and 4E, the remaining photoresist is removed by washing with an alkaline aqueous solution or the like. In this state,
As apparent from FIG. 3E, the product part 21 and the unnecessary part 22 are partially connected via the bridge connection part 23.

Next, in the sixth step, as shown in FIG. 5A, the state shown in FIG. 3E and FIG. A photoresist is deposited on the substrate. As a result, as shown in FIGS. 5B and 6A, the photoresist 16 adheres.

Next, in a seventh step, a mask 1 having a pattern 71 as shown in FIG. 5 (c) and FIG.
7 is brought close to both sides of the metal plate 11 and exposed by the light source 14. This pattern 71 is formed so that only the photoresist 16 at the portion forming the resist remaining portion 61 serving as an insulator, that is, the portion corresponding to the two straight portions opposed to each other through the punched portion 21c, forming the conductor piece 21b is cured. ,
Only a portion corresponding to the portion has a pattern through which light can be transmitted (see FIG. 5E).

Next, in an eighth step, after the development and the removal of the uncured photoresist 16, the steps shown in FIGS.
As shown in (c), the hardened photoresist residue 61 remains at a desired portion of the conductor piece.

Next, by cutting the bridge connection portion 23 from the unnecessary portion 22 of the metal plate 11 and separating the product portion 21,
As shown in FIG. 5 (e), a photoresist remaining portion 61 is provided as an insulator on both surfaces and inner and outer end surfaces of the linear portion of each conductor piece 21b.
Can be obtained. Note that the heat treatment described above can be performed on the one shown in FIG.

As shown in FIG. 7, a ferrite, YIG (yttrium-iron-garnet), or the like is placed on a circular shield plate 21a formed at the center of the product portion (center conductor) 21 obtained in this manner. The ferrimagnetic material 18 is placed.
Then, each conductor piece 21b is bent from the boundary with the shield plate 21a, passes through the peripheral surface of the ferrimagnetic body 18, and is further folded on the upper surface of the ferrimagnetic body 18 so that the conductor pieces 21b overlap each other. At this time, since the remaining photoresist 61 as an insulator is attached to the portion where the conductor pieces 21b overlap as described above, insulation is maintained. Therefore, it is not necessary to separately arrange a sheet-shaped insulator, and the center conductor and the ferrimagnetic material, which are parts of the non-reciprocal circuit element, can be combined into a required shape only by folding the conductor pieces 21b.

[0030]

According to the method of forming an insulating portion of the present invention, an insulating portion having a desired pattern is formed on a desired portion of a molded body having conductivity, irrespective of the shape, size, etc. of the molded body having conductivity. Can be formed. In addition, since the adhesiveness is excellent, there is almost no possibility of displacement or peeling. Moreover, the insulating part formed by the method of the present invention is:
It is possible to hold a good insulating body with a uniform thickness and no pinholes.

[Brief description of the drawings]

FIG. 1 is a process chart for explaining a method of forming an insulating portion according to the present invention.

FIG. 2 is a perspective view of a conduction checker for a semiconductor obtained by applying the method of forming an insulating part according to the present invention.

FIG. 3 is a plan view for explaining a process in a case where the method of forming an insulating portion of the present invention is applied to a central conductor for a non-reciprocal circuit device according to one embodiment.

FIG. 4 is a cross-sectional view for explaining a process in a case where the method for forming an insulating portion of the present invention is applied to a central conductor for a non-reciprocal circuit device according to an embodiment.

FIG. 5 is a plan view for explaining a process in a case where the method for forming an insulating portion of the present invention is applied to a central conductor for a non-reciprocal circuit device according to an embodiment.

FIG. 6 is a cross-sectional view for explaining a process in a case where the method of forming an insulating portion according to the present invention is applied to a central conductor for a non-reciprocal circuit device according to an embodiment.

FIG. 7 is a perspective view showing a state where the center conductor manufactured according to the embodiment is combined with a ferrimagnetic material.

FIG. 8 is an exploded perspective view showing a general structure of a conventionally used non-reciprocal circuit device.

FIG. 9 is an exploded perspective view showing a general structure of a center conductor and a ferrimagnetic material used in a conventionally used nonreciprocal circuit device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal plate 2 Photoresist 3 Mask 4 Light source 5 Electrodeposition bath 11 Metal plate 12 Photoresist 13 Mask 14 Light source 16 Photoresist 61 Photoresist remainder 17 Mask 18 Ferrimagnetic material 21 Product part 21a Shield plate 21b Conductor piece

Claims (4)

[Claims] 1. A method for forming an insulating part, comprising the steps of: attaching a photoresist to the surface of a molded article having conductivity by electrodeposition; and exposing and curing the photoresist. 2. A process for attaching a photoresist to the surface of a molded article having conductivity by electrodeposition, exposing and curing the photoresist through a mask having a desired pattern, and removing an unnecessary portion of the photoresist. A method for forming an insulating part, comprising: 3. The method according to claim 1, further comprising the step of heat-treating the remaining photoresist. 4. A conductive molded article having an insulating part, wherein an insulating part made of a photoresist having a desired pattern is formed on the surface of the molded article having conductivity.