JPH0315537A - Preparation of printed wiring board - Google Patents

Abstract

PURPOSE:To prevent the generation of a crack in a filled resin and to enhance the reliability of a through-hole by a method wherein a required number of metal plate/prepreg composites whose opening parts are filled with a resin filled with a needle-like filler and a metal foil is laminated to the outermost layer of the superposed one through a prepreg and, thereafter, through-holes are formed to the resin parts in the through-holes of the composites by drilling. CONSTITUTION:A prepreg is superposed on the single surface of a metal plate having through- holes and integrally laminated thereto to form a metal plate/prepreg composite wherein the openings on the single side of the through-holes are closed. After these openings are filled with a resin which is filled with a needle-like filler having a particle size of 10mum or more and a length twice or more the particle size, a required number of said composites are superposed one upon another and a metal foil is further arranged to and superposed on the outermost layer of the superposed one through a prepreg if necessary to be laminated thereto and, thereafter, through-holes are formed to the resin parts in the through-holes by drilling. The filled resin applied to the through-holes is prepared by adding 10 - 1,000pts.wt. of the needle like filler such as alumina, silica, talc or calcium carbonate to 100pts.wt. of an arbitrary powdery or liquid resin selected from the resin group used in the prepreg. At this time, when the particle size of the needle-like filler is below 10mum and the length thereof is below twice the particle size, the filler moves after the resin is filled and crack resistance is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a wiring board used in electronic equipment, electrical equipment, computers, communication equipment, etc.

[Conventional technology]

Conventionally, in the manufacturing method of wiring boards using metal plates,
In the case of phenolic resin prepreg, ioox
Q/d around 50Kvcd for epoxy resins and polyimide resins, and 30K9~ for unsaturated polyester resins, and is laminated or shaped, filling all the holes of the molten resin from the Bripreg and integrating it. However, this method has the drawback that cracks occur in the filled resin, reducing the reliability of the through holes.

[Problem that the invention seeks to solve]

As described in the prior art section, filling the through holes with molten resin from prepreg has the disadvantage that cracks are likely to occur in the filled resin. The present invention has been made in view of the above-mentioned problems in the prior art, and its object is to provide a method for manufacturing a wiring board that does not cause cracks in the filled resin and has good through-hole reliability.

1 (2) [Means for resolving the problem] The present invention is a metal plate in which a prepreg is layered on one side of a metal plate having a through hole, and the opening on one side of the through hole is closed by laminating and integrating the prepreg.
After preparing the prepreg composite, the openings are filled with a needle-shaped filler-containing resin having a diameter of 10 microns or more and a length of at least twice the diameter, and then the metal plate. After stacking the appropriate number of pre-reg composites, and further assembling the laminate with metal foil arranged as necessary via the prepreg on the outermost layer, we drilled through holes in the resin part of the ticket. Due to the manufacturing method of the wiring board, which is characterized by the fact that the filler and the resin do not separate or cause variations, it is possible to improve the crack and leak resistance of the filled resin. Explain in detail.

Metal plates used in the present invention include copper, aluminum, iron,
2. Sokel, zinc chips alone, alloys, and composites can be used, and the thickness of the metal plate is not particularly limited. It is desirable that b is preferably between 0.1 and 1, and as b0 prepreg. Phenolic resin, cresol resin, epoxy resin, unsaturated. Japanese polyester resin, polyimide resin, polybutadiene resin, polyphenylene sulfide resin,
Woven fabrics made of resins such as polybutylene terephthalate resin, polyethylene terephthalate resin, and fluorinated resin, combined with inorganic fibers such as glass and ashest, organic fibers such as polyvinyl alcohol, polyester, polyacrylic, and polyamide, and natural fibers such as cotton. , non-woven fabric, mat, paper, or a combination thereof, and dried, and if necessary, a filler may be added to the resin. As the filler-containing resin to be filled in the through holes, any powder or liquid resin from the group of sticky resins used in the above-mentioned prepreg can be used. Acicular fillers such as alumina, silica, glass powder, talc, calcium carbonate, aluminum hydroxide, etc., with a length of 10 microns or more and a length of at least twice the diameter, preferably 10 to 100
It is necessary to add 0 parts. This is because if the diameter of the acicular filler is less than 10 microns and the length is less than twice the diameter, the filler will move after being filled with resin, resulting in a decrease in the sagging and soaking resistance. For integration of pile-up and collapse (in section 8, use any method such as multi-stage press method, double belt method, multi-roll method, drum method, etc.)
can be done. For step 6 of drilling a through hole in the resin part within the through hole, a normal method can be used.

The present invention will be explained below based on examples.

Example thickness 9. Six pieces of 2κH epoxy resin-impregnated glass prepreg were stacked with 0.5-thick copper plates with through holes at the required positions, and pressed into shape using a multistage press at a pressure of 5 Kq/i at 100°C.
A metal plate/prepreg composite with closed holes on one side was obtained by laminating and integrating the holes, and to open the composite, 15 microns in diameter and 3 in length were added to 100 parts of epoxy resin containing a hardening agent.
After filling resin containing filler with 400 parts of 5 micron E-glass powder using the squeegee method, stack 4 sheets with the filled part on top, and then add 35 micron thick copper foil as the outermost layer with one sheet of the same prepreg as above interposed. '{fl-The stacked laminate was pressed in a multistage press at a pressure of 20 Kq/ctA and 9 at 170°C.
A wiring board was obtained by molding m layers for 0 minutes.

Comparative Example A filler-containing resin was used, in which 400 parts of E-glass powder with a diameter of 5 microns and a length of 8 microns was added to 100 parts of an epoxy resin containing a hardening agent. I fell asleep.

Table 1 shows the performance of the wiring boards of Examples and Comparative Examples.

Table 1 [Effects of the Invention] The present invention is constructed and maintained as described above. The wiring board obtained by the wiring board manufacturing method described in claim 1 has good resin filling properties and has the effect of improving crack resistance.

Claims (1)

[Claims] (1) A metal plate with one side of the through hole closed by prepreg layered on one side of the metal plate and integrated with the laminated material.
After creating the prepreg composite, this aperture has a diameter of 10 mm.
After filling resin containing needle-like filler with a length of microns or more and at least twice the diameter, the required number of metal plate/prepreg composites are stacked, and metal foil is placed as necessary on the outermost layer via the prepreg. 1. A method for manufacturing a wiring board, which comprises: after laminating the prepared laminates together, through-holes are formed in resin portions within the through-holes.