JP2001185833A - Method and device for manufacturing multilayered printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device by which a warp-free multilayered printed wiring board can be manufactured surely and efficiently. SOLUTION: In the method of manufacturing a multilayered printed wiring board which is constituted by forming photo-setting insulating resin layers 3 on both surfaces of a board 2 carrying conductor circuits, the photo-setting insulating resin layers 3 are formed on both surfaces of the board 2, and the resin layers 3 are photo-set by simultaneously irradiating both surfaces of the board 2 with light rays.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a multilayer printed wiring board having a photocurable insulating resin layer formed thereon.

[0002]

2. Description of the Related Art Conventionally, in a method of manufacturing a multilayer printed wiring board, when photo-curing an insulating resin layer having photo-curability, light irradiation is performed as follows. That is,
Light is applied to the insulating resin layers 3 formed on both surfaces of the substrate 2 one by one using the manufacturing apparatus 9 shown in FIG. The manufacturing apparatus 9 includes a light source 92 for irradiating the insulating resin layer 3 on the substrate 2 with light, and a roller conveyor 93 for horizontally transporting the substrate 2 below the light source 92.

[0003] First, the substrate 2 on which the insulating resin layer 3 is formed on both sides is placed on the roller conveyor 93 with the front side 21 up. Then, the substrate 2 is transported by the roller conveyor 93 and passes below the light source 92. At this time, the light is applied to the insulating resin layer 3 on the front side surface 21 of the substrate 2 below the light source 92. Thus, the insulating resin layer 3 on the front surface 21 of the substrate 2 is light-cured. Next, the substrate 2 is turned upside down so that the back side surface 22 is turned upward, and passes under the light source 92 in the same manner as described above. Thus, the insulating resin layer 3 on the back side surface 22 of the substrate 2 is light-cured.

As described above, the insulating resin layers 3 formed on both surfaces of the substrate 2 are light-cured. Also, by sequentially loading a large number of substrates 2 into the manufacturing apparatus 9, the insulating resin layers 3 formed on both surfaces thereof are cured, and a large number of multilayer printed wiring boards are sequentially manufactured (FIG. 3). Note that the front side surface 21 and the back side surface 22 are convenient names representing one surface and the other surface of the substrate 2.

[0005]

However, in the above-mentioned conventional method for manufacturing a multilayer printed wiring board, as described above, the insulating resin layers 3 formed on both sides of the substrate 2 are irradiated with light one by one. Thus, for example, if the front side 21 is irradiated with light first, only the insulating resin layer 3 on the front side 21 is cured before the insulating resin layer 3 on the back side 22 is cured (FIG. 4A). . Therefore, as shown in FIG. 4B, stress (arrow B) concentrates on the front side surface 21 of the substrate 2 and the substrate 2 may be warped. In addition, this may cause cracking or peeling of the insulating resin layer 3 formed on the substrate 2.

In the above manufacturing method, the substrate 2 which has been irradiated with light on the insulating resin layer 3 on one side is turned over,
It is necessary to irradiate light to the insulating resin layer 3 on the opposite side.
Therefore, there is a possibility that an operation error may occur such that the substrate 2 whose one surface is not processed without being inverted is paid out to the next process, or the same surface is irradiated with light more than necessary. It is also disadvantageous in terms of work efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and a method and an apparatus for manufacturing a multilayer printed wiring board capable of reliably and efficiently obtaining a multilayer printed wiring board without warpage of a substrate. It is intended to provide.

[0008]

According to a first aspect of the present invention, there is provided a method of manufacturing a multilayer printed wiring board having a photocurable insulating resin layer formed thereon, wherein both surfaces of a substrate provided with a conductive circuit are photocured. The method for manufacturing a multilayer printed wiring board is characterized in that after the insulating resin layer having the property is formed, the insulating resin layer is photo-cured by simultaneously irradiating light from both sides of the substrate.

What is most notable in the present invention is that the insulating resin layer is cured by simultaneously irradiating light from both sides of the substrate. Examples of the insulating resin layer include an interlayer insulating layer having via holes and a solder resist layer having solder pads.

Next, the operation and effect of the present invention will be described.
In the method for manufacturing a multilayer printed wiring board, since the light is simultaneously irradiated from both surfaces of the substrate, the insulating resin layers on both surfaces of the substrate can be simultaneously photo-cured. Therefore, stress due to curing of the insulating resin layer does not concentrate on one surface of the substrate, and there is no possibility that the substrate is warped. Further, as a result, there is no possibility that cracks or peeling may occur in the insulating resin layer formed on the substrate.

Further, in the above manufacturing method, since the insulating resin layers on both surfaces of the substrate are irradiated with light at the same time, it is not necessary to turn over the substrate and irradiate light again. Therefore, there is no possibility that an operation error such as paying out a substrate having one surface left unprocessed to the next process or irradiating the same surface with light more than necessary occurs. Also, work efficiency is improved.

As described above, according to the present invention, it is possible to provide a method for manufacturing a multilayer printed wiring board capable of reliably and efficiently obtaining a multilayer printed wiring board without warpage of a substrate.

Next, as in the second aspect of the present invention, it is preferable that the insulating resin layer is light-cured while the substrate is held substantially vertically. Thus, the portion where the insulating resin layer is formed on the front surface or the rear surface of the substrate is not brought into contact with the manufacturing apparatus or the like (see FIGS. 1 and 2). Therefore, there is no possibility that the insulating resin layers formed on both surfaces of the substrate are damaged or foreign matter is attached. As a means for holding the substrate in a substantially vertical state, for example, there is a means for gripping an end of the substrate and suspending the substrate from above (see FIG. 1).

Next, it is preferable that both sides of the substrate be irradiated with light while the substrate is transported in a substantially vertical state. This makes it possible to irradiate a large number of the substrates with light more efficiently. Therefore, the production efficiency of the printed wiring board is improved. Also,
Since the substrate is transported in a substantially vertical state, there is no possibility that the insulating resin layers on both sides of the substrate are damaged or foreign matter adheres.

Next, as in the fourth aspect of the present invention, the light irradiation on the substrate is performed when the shortest distance from the substrate is 100 to 5 mm.
It is preferable to use a light source arranged at a position of 00 mm. This makes it possible to irradiate the entire surface of the substrate with light substantially uniformly and sufficiently. Therefore, the insulating resin layer on the entire surface of the substrate can be uniformly photo-cured, and furthermore, warpage of the substrate and cracking and peeling of the insulating resin layer can be more reliably prevented.

When light irradiation is performed from a light source whose shortest distance from the substrate is less than 100 mm, the degree of photo-curing of the insulating resin layers formed on both surfaces of the substrate varies depending on the position on the substrate, and the substrate warps. Also, cracking and peeling of the insulating resin layer may occur. On the other hand, when light irradiation is performed from a light source having a minimum distance of more than 500 mm from the substrate, it becomes difficult to sufficiently cure the insulating resin layers formed on both surfaces of the substrate.

The shortest distance from the substrate to the light source is more preferably 300 to 400 mm. In this case, the entire surface of the substrate can be evenly and sufficiently irradiated with light.

Next, according to a fifth aspect of the present invention, in a manufacturing apparatus for a multilayer printed wiring board having a photo-curable insulating resin layer formed thereon, the manufacturing apparatus is configured to set the substrate in a substantially vertical state. A holding means for holding, and a pair of light sources arranged so as to be able to irradiate light to the front side and the back side of the substrate, respectively, with respect to the insulating resin layers on both sides of the substrate held by the holding means; There is an apparatus for manufacturing a multilayer printed wiring board characterized in that light is irradiated simultaneously by the pair of light sources.

Thus, both sides can be irradiated simultaneously with light while holding the substrate in a substantially vertical state. Therefore, as described in the description of the first aspect of the present invention, it is possible to prevent the substrate from being warped, scratched, and adhered with foreign substances.
It can improve production efficiency and prevent work errors. That is, according to the present manufacturing apparatus, it is possible to reliably and efficiently obtain a multilayer printed wiring board free from substrate warpage, scratching, and adhesion of foreign matter.

Next, as in the invention according to claim 6, the holding means is attached to the transport means, and irradiates both surfaces of the substrate with light while transporting the substrate by the transport means. It is preferred that it is comprised. This makes it possible to irradiate a large number of the substrates with light more efficiently. Therefore, the production efficiency of the printed wiring board is improved.

Next, it is preferable that the shortest distance between the light source and the substrate is 100 to 500 mm. Thus, as described in the description of the third aspect of the present invention, the insulating resin layer on the entire surface of the substrate can be uniformly photo-cured, and the warpage of the substrate and cracks and peeling in the insulating resin layer can be further ensured. Can be prevented. The criticality of limiting the numerical value regarding the shortest distance between the light source and the substrate is the same as in the case of the third aspect of the present invention.

The shortest distance between the light source and the substrate is 3
More preferably, the thickness is from 00 to 400 mm. In this case, the entire surface of the substrate can be evenly and sufficiently irradiated with light.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A method for manufacturing a multilayer printed wiring board according to an embodiment of the present invention will be described with reference to FIG. The manufacturing method of this example is a method of manufacturing a multilayer printed wiring board provided with an insulating resin layer 3 having photocurability, and uses a manufacturing apparatus 1 described below.

That is, as shown in FIG. 1, the manufacturing apparatus 1 for a multilayer printed wiring board includes a holding means 11 for holding the substrate 2 in a substantially vertical state, and a front surface 21 and a rear surface 2 of the substrate 2.
2 and a pair of light sources 12 arranged so as to be able to irradiate light. The manufacturing apparatus 1 is configured to simultaneously irradiate the insulating resin layers 3 on both surfaces of the substrate 2 held by the holding means 11 with the pair of light sources 12.

The holding means 11 is provided with the transport means 1.
3 is attached. The shortest distance D between the light source 12 and the substrate 2 is 375 mm. Also, as shown in FIG.
A reflection plate 121 that reflects light to the side is provided.

The method of manufacturing the multilayer printed wiring board of this embodiment is as follows.
When photo-curing the insulating resin layers 3 formed on both surfaces of the substrate 2, the manufacturing apparatus 1 configured as described above is used to hold the substrate 2 in a substantially vertical state. Light is irradiated simultaneously from both sides of the substrate 2.

That is, as shown in FIG.
Of the substrate 2 by the holding means 11
By holding and suspending from above, the substrate 2
Is held substantially vertically. The insulating resin layer 3 is not formed on the end 25. Further, as shown by an arrow A in FIG. 1, light is applied to both surfaces of the substrate 2 while the substrate 2 is transported in a substantially vertical state by the transport means 13. The insulating resin layer 3 is formed of an epoxy resin mixed with an acrylic photocurable resin.

Next, a method for manufacturing the multilayer printed wiring board of this embodiment will be specifically described. That is, first, the insulating resin layer 3 is applied to both sides of the substrate 2 having the conductor circuits formed on both sides, and dried. Next, exposure and development are performed on the insulating resin layer 3 to form a via hole. Next, as described above, the substrate 2 is transported by the transport unit 13 while being held in a substantially vertical state by the holding unit 11 (FIG. 1).

Then, the substrate 2 is connected to the pair of light sources 12.
The light source 12 simultaneously irradiates the front side surface 21 and the back side surface 22 of the substrate 2 with light for about one minute while transporting the same. The transfer speed of the substrate 2 is 2 cm / sec. At this time, the integrated light amount of the irradiated light is about 6000 mJ per side. This gives
The insulating resin layers 3 on the front side surface 21 and the back side surface 22 of the substrate 2 are simultaneously light-cured.

Further, the substrate 2 is put into a heat treatment furnace, and the photo-cured insulating resin layer 3 is further cured by heat. Next, the surface of the insulating resin layer 3 is subjected to a roughening treatment to form an interlayer insulating layer, and a conductive circuit is further provided thereon. The formation of the interlayer insulating layer and the conductor circuit is repeated, and a solder resist having solder pads is applied to the outermost layer to manufacture a multilayer printed wiring board.

Next, the operation and effect of this embodiment will be described. In the method for manufacturing a multilayer printed wiring board, since the insulating resin layers 3 formed on both surfaces of the substrate 2 are simultaneously irradiated with light, the insulating resin layers 3 can be light-cured simultaneously. Therefore, the stress due to the hardening of the insulating resin layer 3 does not concentrate on one surface of the substrate 2, and there is no possibility that the substrate 2 is warped (see FIG. 4B). Thus, there is no possibility that cracks or peeling may occur in the insulating resin layer formed on the substrate 2.

In the above manufacturing method, since the substrate 2 is held in a substantially vertical state and light is irradiated, the front surface 21 or the rear surface 22 of the substrate 2 does not come into contact with the manufacturing apparatus 1 or the like. Therefore, there is no possibility that the insulating resin layers 3 formed on both surfaces of the substrate 2 are damaged or foreign substances are attached.

In the above manufacturing method, since the insulating resin layers 3 on both surfaces of the substrate 2 are irradiated with light at the same time, it is not necessary to turn over the substrate 2 and irradiate light again. Therefore, there is no possibility that an operation error such as paying out the substrate 2 having one surface left unprocessed to the next process or irradiating the same surface with light more than necessary occurs. Also, work efficiency is improved.

In order to irradiate both sides of the substrate 2 while transporting the substrate 2 in a substantially vertical state, a large number of substrates 2
Light can be more efficiently applied to the printed wiring board, and the production efficiency of the printed wiring board is improved. The substrate 3 and the light source 12
Since the shortest distance from the substrate 3 is 375 mm, the entire surface of the substrate 3 can be sufficiently and substantially uniformly irradiated with light. Therefore, the insulating resin layer 3 on the entire surface of the substrate 2 can be uniformly photo-cured, and the warpage of the substrate 2 and cracking and peeling of the insulating resin layer 3 can be more reliably prevented.

Embodiment 2 In this embodiment, as shown in FIG.
1 is an example of a manufacturing apparatus 10 using a roller 101 that sandwiches two opposite ends 25 of a substrate 2 from both sides. That is,
A large number of two pairs of rollers 101 are arranged at the upper part and the lower part of the manufacturing apparatus 10, respectively. Each roller 101 rotates at the same speed (arrow R), and also serves as a transport unit for the substrate 2. Then, the substrate 2 is held and transported in a substantially vertical state by sandwiching the end portion 25 of the substrate 2 between the pair of rollers 101. Other configurations are the same as those of the first embodiment.

In the case of this embodiment, the substrate 2 can be held and transported at a predetermined position more accurately. In addition, the third embodiment has the same functions and effects as the first embodiment.

The present invention relates to a method of forming an interlayer insulating layer composed of a composite of a thermosetting resin and a thermoplastic resin and mixing an acrylic photocurable resin into an acrylic resin to form an acrylic resin. It is more effective when used as an insulating resin layer applied to a substrate. Examples of the thermosetting resin include an epoxy resin, a phenol resin, a triazine resin, a polyolefin resin, a polyphenyl ether resin, and a polyimide resin.

[0038]

As described above, according to the present invention, it is possible to provide a method and an apparatus for manufacturing a multilayer printed wiring board capable of reliably and efficiently obtaining a multilayer printed wiring board without warpage of a substrate. it can.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method and an apparatus for manufacturing a printed wiring board according to a first embodiment.

FIG. 2 is a diagram illustrating a method and an apparatus for manufacturing a printed wiring board according to a second embodiment.

FIG. 3 is an explanatory view of a method and an apparatus for manufacturing a printed wiring board in a conventional example.

FIG. 4 is an explanatory view of warpage of a substrate in a conventional example.

[Explanation of symbols]

 1. . . Manufacturing equipment, 11. . . Holding means, 12. . . Light source, 13. . . 1. transport means; . . Substrate, 3. . . Insulating resin layer,

Claims (7)

[Claims] 1. A method for manufacturing a multilayer printed wiring board comprising a photocurable insulating resin layer formed on a substrate provided with a conductive circuit, wherein the photocurable insulating resin layer is formed on both surfaces of the substrate. A method of manufacturing a multilayer printed wiring board, comprising: irradiating light from both sides of the substrate at the same time to light cure the insulating resin layer. 2. The method for manufacturing a multilayer printed wiring board according to claim 1, wherein said substrate is held substantially vertically and said insulating resin layer is photo-cured. 3. The method according to claim 1, wherein both sides of the substrate are irradiated with light while the substrate is transported in a substantially vertical state. 4. The method according to claim 1, wherein:
The light irradiation on the substrate is performed when the shortest distance from the substrate is 100 to
A method for producing a multilayer printed wiring board, wherein the method is performed from a light source arranged at a position of 500 mm. 5. A multilayer printed wiring board manufacturing apparatus having a photocurable insulating resin layer formed thereon, the manufacturing apparatus comprising: holding means for holding a substrate in a substantially vertical state; A pair of light sources disposed so as to be able to irradiate light to the rear side surface, and the insulating resin layers on both surfaces of the substrate held by the holding means are simultaneously irradiated with light by the pair of light sources. An apparatus for manufacturing a multilayer printed wiring board, comprising: 6. The apparatus according to claim 5, wherein the holding means is attached to the transfer means, and irradiates both surfaces of the substrate with light while transferring the substrate by the transfer means. For manufacturing a multilayer printed wiring board. 7. The manufacturing apparatus according to claim 5, wherein a shortest distance between the light source and the substrate is 100 to 500 mm.