JP3216155B2 - Wiring board manufacturing method - Google Patents

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 wiring board.

[0002]

2. Description of the Related Art In general, a wiring board is formed on the entire upper surface of a substrate including a conductive layer in order to protect a conductive layer formed on the upper surface of the substrate made of resin, ceramic, or the like and to secure insulation. It has a structure provided with an insulating layer.

When an electronic component such as an IC chip is mounted on such a wiring board, a planar rectangular opening is formed in a portion of the insulating layer corresponding to a predetermined portion of the conductive layer. An electronic component such as an IC chip is mounted on a wiring board by bonding a bump electrode or the like of an electronic component such as an IC chip to the conductive layer exposed through the wiring via solder or the like. In this case, there is a screen printing method as a method for forming an insulating layer having a planar rectangular opening. According to this screen printing method, a screen mask having a predetermined pattern is arranged in parallel on a substrate at a predetermined interval, and the insulating ink is extruded by pressing the screen mask with a squeegee. For example, an insulating layer having a square opening can be formed easily and in a short time.

[0004]

However, in such a conventional method of manufacturing a wiring board, since the insulating ink has viscosity, bleeding occurs in the insulating layer immediately after printing, and a screen mask is formed with a squeegee. Is pressed, the screen mask expands and contracts, causing a shift in the printing position.
There is a problem that the size is about 0 μm square and the miniaturization is limited. The same applies to the case where a conductive layer is patterned on a substrate by screen printing, for example, in a hybrid IC.
There is a problem that the degree of S (line and space) is limited and there is a limit in miniaturization. An object of the present invention is to provide a method of manufacturing a wiring board that can be further miniaturized.

[0005]

According to the present invention, when a printing layer is formed by screen printing in a manufacturing process of a wiring board, at least the printing layer forming region is formed in a region other than the printing layer forming region where the printing layer is to be formed. A photoresist layer is provided around the print layer forming area , and the print layer forming area is
Screen mask with smaller ink passage pattern
The printed layer is formed by screen printing using a said printing
After flowing and spreading the layer, the photoresist layer is peeled off.

[0006]

According to the present invention, a photoresist layer capable of forming a fine pattern is formed at least around the print layer forming region in a region other than the print layer formation region. Print layer flows and spreads
A screen mask having an ink passage pattern smaller by an amount
Since the printing layer is formed by screen printing using a mask, the printing range can be regulated at the end face of the photoresist layer, thereby preventing the printing layer immediately after printing from oozing out of a predetermined print forming area. Even if the screen mask expands and contracts and the printing position slightly shifts , the printing layer can be flowed using the viscosity of the printing layer.
With the configuration in which the print layer is expanded , the print layer can be formed only in the predetermined print layer formation region, and therefore, the size can be further reduced.

[0007]

1 to 5 show an example of each manufacturing process when the present invention is applied to a method for manufacturing a wiring board having an insulating layer having an opening. Therefore, a method of manufacturing a wiring board including an insulating layer having an opening will be described with reference to these drawings.

First, as shown in FIG. 1, a conductive layer 2 is patterned on the upper surface of a substrate 1 made of resin, ceramic, or the like. Next, a photoresist layer 3 having a thickness of, for example, about 50 μm is provided on the entire surface. In this case, the film-shaped photoresist may be thermocompression-bonded, or may be applied by spin coating or the like. Next, for example, 1
Irradiation with light such as ultraviolet rays is performed by using a mask having a predetermined pattern corresponding to the opening forming region 4 (see FIG. 5) in which the opening of the 00 μm square is to be formed. The layer 3 is exposed. Thereafter, when development is performed, as shown in FIG. 2, unnecessary portions of the photoresist layer 3 other than the opening formation region 4 are peeled off, and the photoresist layer 3 remains only in the opening formation region 4. Next, by performing screen printing using a screen mask (not shown) having an island pattern slightly larger than the opening forming region 4 and insulating ink, as shown in FIG.
An insulating ink layer 5 is applied to a thickness of about 10 to 25 μm on the entire surface except for the photoresist layer 3 and its surroundings.
In this case, although the size of the island pattern of the screen mask depends on the viscosity of the insulating ink, the size of the opening forming region 4 is not limited.
Is larger by about 20 to 30 μm on each side than the size of 100 μm square. As the insulating ink, one obtained by dissolving an epoxy resin in an organic solvent is used. After that, if left to some extent, the insulating ink layer 5 flows and spreads,
As shown in FIG. 4, the entire surface except the photoresist layer 3 is covered with the insulating ink layer 5 by being dammed at the end face of the photoresist layer 3. Next, the insulating ink layer 5 is dried to have a thickness of about 10 to 20 μm, and then the photoresist layer 3 is peeled off. As shown in FIG. An insulating layer 7 having 6 is formed. Thus, a wiring board including the insulating layer 7 having the opening 6 is manufactured.

In the wiring board manufactured as described above,
In a state where the photoresist layer 3 capable of forming a fine pattern is formed in the region other than the region where the insulating layer 7 is to be formed, that is, in the region other than the region where the insulating layer 7 is to be formed. Insulation layer 7 by screen printing
Is formed, the printing range can be regulated by the end face of the photoresist layer 3, thereby preventing the insulative ink layer 5 immediately after printing from oozing out of the area where the predetermined insulating layer 7 is to be formed. Even if the screen mask expands and contracts and the printing position slightly shifts,
By utilizing the viscosity of the insulating ink layer 5, the insulating layer 7 can be formed only in the area where the predetermined insulating layer 7 is to be formed.
The size can be further reduced to about m square.

Next, FIGS. 6 to 10 show respective manufacturing steps of an example when the present invention is applied to a method for manufacturing a wiring board having a conductive pattern by screen printing. Therefore, a method of manufacturing a wiring board provided with a conductive pattern by screen printing will be described with reference to these drawings in order.

First, as shown in FIG. 6, a photoresist layer 12 is provided on the upper surface of a substrate 11 made of resin, ceramic, or the like. In this case, the film-shaped photoresist may be thermocompression-bonded, or may be applied by spin coating or the like. Next, the photoresist layer 12 in the conductive layer forming region 13 is exposed by irradiating light such as ultraviolet rays using a mask having a predetermined pattern corresponding to the conductive layer forming region 13 (see FIG. 10) where the conductive layer is to be formed. I do. After this, when developed,
As shown in FIG. 7, unnecessary portions of the photoresist layer 12 in the conductive layer formation region 13 are peeled off, and the photoresist layer 12 remains only in a region other than the conductive layer formation region 13. Next, screen printing is performed by using a screen mask (not shown) having an ink passage pattern slightly smaller than the conductive layer forming region 13 and conductive ink, thereby forming the conductive layer forming region 4 as shown in FIG.
A conductive ink layer 14 is applied to the center of the substrate. in this case,
The size of the ink passage pattern of the screen mask depends on the viscosity of the conductive ink, but is set to be smaller by about 20 to 30 μm than the size of the conductive layer forming region 13 of 100 μmL / S. As the conductive ink, one obtained by dissolving a conductive powder of carbon, silver, copper or the like and an epoxy resin in an organic solvent is used. After that, if left to some extent, the conductive ink layer 14 flows and spreads. However, as shown in FIG. 9, the entire surface of the conductive layer forming region 13 is blocked by the end face of the photoresist layer 12 and the conductive ink layer 14 will be covered. Next, after the conductive ink layer 14 is dried and the photoresist layer 12 is peeled off, a conductive layer 15 is formed in a portion corresponding to the conductive layer forming region 13 as shown in FIG. Thus, a wiring board having a conductive pattern by screen printing is manufactured.

[0012]

As described above, according to the present invention, in a region other than the print layer formation region, at least a photoresist layer capable of forming a fine pattern is formed around the print layer formation region in a state where the print layer formation region is formed. In the print layer formation area
On the other hand, the ink passage that is smaller by the amount that the print layer flows and spreads
Since the printing layer is formed by screen printing using a screen mask having a pattern , the printing range can be regulated at the end face of the photoresist layer. It can prevent bleeding, and even if the screen mask expands and contracts and the printing position slightly shifts , the printing layer is made to flow and spread using the viscosity of the printing layer.
By doing so, it is possible to form a print layer only in a predetermined print layer formation region, and therefore, it is possible to further reduce the size.

In the above-described embodiment, for example, as shown in FIG. 2, a photoresist layer 3 is provided over the entire opening forming region 4, and, for example, as shown in FIG.
Although the photoresist layer 12 is provided on the entire area other than the area 3, the essential point is that the printing range can be regulated at the end face of the photoresist layer. Therefore, the photoresist layer is provided at least around the area to be screen-printed. It should just be.

[0014]

As described above, according to the present invention, in a region other than the print layer formation region, at least a photoresist layer capable of forming a fine pattern is formed around the print layer formation region in a state where the print layer formation region is formed. Since the printing layer is formed by screen printing, the printing range can be regulated at the end face of the photoresist layer, and therefore, it is possible to prevent the printing layer immediately after printing from oozing out of a predetermined printing layer forming area. In addition, even if the screen mask expands and contracts and the printing position slightly shifts, the printing layer can be formed only in a predetermined printing layer forming area by utilizing the viscosity of the printing layer. It can be miniaturized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which a conductive layer is patterned on an upper surface of a substrate and then a photoresist layer is formed on the entire surface in manufacturing a wiring substrate according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which an unnecessary portion of a photoresist layer is peeled off in manufacturing the wiring board of the embodiment.

FIG. 3 is a cross-sectional view showing a state immediately after an insulating ink layer is applied by screen printing in manufacturing the wiring board of the embodiment.

FIG. 4 is a cross-sectional view showing a state in which an insulating ink layer flows and is blocked at an end surface of a photoresist layer in manufacturing the wiring board of the embodiment.

FIG. 5 is a cross-sectional view showing a state where an opening is formed in an insulating layer by removing a photoresist layer in manufacturing the wiring board of the embodiment.

FIG. 6 is a cross-sectional view showing a state in which a photoresist layer is formed on the upper surface of a wiring board when manufacturing a wiring board according to another embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a state in which an unnecessary portion of a photoresist layer is removed in manufacturing a wiring board according to another embodiment.

FIG. 8 is a cross-sectional view showing a state immediately after a conductive ink layer is applied by screen printing in manufacturing a wiring board according to another embodiment.

FIG. 9 is a cross-sectional view showing a state in which a conductive ink layer flows and is blocked at an end surface of a photoresist layer in manufacturing a wiring board according to another embodiment.

FIG. 10 is a cross-sectional view showing a state in which a conductive layer is patterned on a substrate by removing a photoresist layer when manufacturing a wiring substrate according to another embodiment.

[Explanation of symbols]

 Reference Signs List 1 substrate 2 conductive layer 3 photoresist layer 4 opening forming region 5 insulating ink layer 6 opening 7 insulating layer 11 insulating substrate 12 photoresist layer 13 conductive layer forming region 14 conductive ink layer 15 conductive layer

Claims (3)

(57) [Claims] When a printing layer is formed by screen printing in a process of manufacturing a wiring board, a photoresist layer is provided at least around the printing layer forming region in a region other than the printing layer forming region where the printing layer is to be formed. In the printing layer forming area, an ink passage pattern smaller than the printing layer forming area is provided.
A method for manufacturing a wiring board , comprising: forming a printed layer by screen printing using a screen mask having the printed layer, spreading the printed layer by flowing , and then removing the photoresist layer. 2. A photoresist layer is provided on at least a periphery of an upper surface of a conductive layer patterned on an upper surface of a substrate in an opening forming region where an insulating layer opening is to be formed, and a photoresist layer other than the opening forming region is provided. Region from the opening forming region
An insulating layer is formed by screen printing using a screen mask having a large island pattern, and the insulating layer flows.
A method for manufacturing a wiring board, comprising forming an insulating layer opening in a portion corresponding to the opening forming region by peeling off the photoresist layer after spreading . 3. A photoresist layer is provided on at least the periphery of the conductive layer forming region in a region other than the conductive layer forming region where the conductive layer is to be patterned on the upper surface of the substrate, and the conductive layer is formed in the conductive layer forming region. Ink passage smaller than the formation area
A conductive layer is formed by screen printing using a screen mask having a pattern, and the conductive layer is flowed and spread.
And thereafter peeling off the photoresist layer.