JPH1197806A - Surface-mounting wiring substrate and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface-mounting wiring substrate where thermal radiation is readily performed and the required functions can be performed all the time, even when the semiconductor element having the large amount of heat radiation accompanied by operation is provided and mounted, and a manufacturing method thereof. SOLUTION: A substrate has at least one layer of heat-radiating substrate, which has an inter-layer connecting hole 2 that penetrates in the thickness direction and connects the wiring patterns on both main-surface, a thin epoxy resin layer 3 covering the surface of a heat radiating plate 1 including the inner wall surface of the inter-layer connecting hole 2, and a conductor plated layer 4 that is formed on the epoxy resin layer 3 at inner wall surface of the inter-layer connecting hole 2, and electrically connects the corresponding wiring patterns.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mounting wiring board and a method for manufacturing the same, and more particularly, to a high-speed operation type wiring board for surface mounting suitable for mounting and mounting a semiconductor element having a large amount of heat generation and a method for manufacturing the same. About the method.

[0002]

2. Description of the Related Art Memory modules and the like in which a semiconductor element requiring high-speed operation is mounted and mounted on a main surface are widely used in various electronic devices. As this kind of module wiring board, a surface mounting wiring board using glass / epoxy resin as an insulating base material is generally used. That is, circuit devices such as memory modules are required to be shorter, smaller, lighter, more compact, and lower in cost. In response to such demands, glass-epoxy resin-based wiring boards having high electrical insulation and mechanical strength are generally used.

[0003]

However, the following inconvenience is recognized in the surface mounting wiring board having the above-mentioned structure. In general, since the electrical conductivity of a substance is proportional to the thermal conductivity, in the case of an insulating substrate having a high electrical insulation (low electrical conductivity), that is, a glass-epoxy resin-based substrate, This means that the conductivity is low and the heat dissipation is inferior.

[0004] Therefore, with the high density mounting on the surface mounting wiring board, or the increase in the overall heat generation or the improvement of the heat generation density due to the mounting and mounting of the semiconductor element having a large operating heat generation, the required functions are sufficiently provided. May not be able to be fully demonstrated. That is, the heat generated by each component cannot be sufficiently radiated only from the surface (exposed surface) of the component itself, so that the temperature of the component itself rises, and the performance inevitably decreases.

The present invention has been made in view of the above circumstances. Even when a semiconductor element generating a large amount of heat during operation is mounted and mounted, heat is easily dissipated, and required functions can be constantly exerted. It is an object of the present invention to provide a wiring board for surface mounting and a method for manufacturing the same.

[0006]

According to a first aspect of the present invention, there is provided a heat dissipating plate having an interlayer connection hole penetrating in a thickness direction and connecting between wiring patterns on both main surfaces, A thin epoxy resin layer covering the surface of the heat-radiating plate including the inner wall surface of the hole, and a conductor plating formed on the epoxy resin layer surface of the inner wall surface of the interlayer connection hole and electrically connecting the corresponding wiring patterns. And a heat-radiating wiring board having at least one layer.

According to a second aspect of the present invention, in the wiring board for surface mounting according to the first aspect, the heat dissipating wiring board is disposed on the outer layer side.

According to a third aspect of the present invention, there is provided a heat radiating plate, in which a hole for interlayer connection penetrating in a thickness direction thereof is formed, and an epoxy resin layer having a substantially uniform thickness is formed on the surface of the heat radiating plate. A method of manufacturing a surface mounting wiring board, comprising: a step of forming a coating; and a step of forming an interlayer connection portion and a wiring pattern on an epoxy resin layer surface including the inside of the interlayer connection hole.

According to the first and second aspects of the present invention, while the electrical insulation is ensured by the epoxy resin layer, the thermal conductivity and the mechanical strength are maintained by the heat radiating plate. Can be easily reduced in size and weight. In other words, it functions as a mounting wiring board suitable for a configuration such as a memory module that is compact and maintains and exhibits high performance.
According to the third aspect of the present invention, the compact and high performance is maintained.
A mounting wiring board suitable for a configuration such as a memory module to be exhibited can be easily provided at low cost.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described below with reference to FIGS. 1, 2 and 3. FIG.

FIG. 1 is a sectional view showing the structure of a main part of a wiring board for surface mounting according to a first embodiment. In FIG. 1, 1
Is a heat radiating plate having an interlayer connection hole 2 penetrating in the thickness direction and connecting between the wiring patterns on both main surfaces. Here, the heat radiating plate 1 is a plate made of a metal having good thermal conductivity such as an iron or aluminum plate and having a suitable mechanical strength, and is suitable for use and size of the surface mounting wiring board. Generally, however, the thickness is about 0.05 to 0.3 mm, and the diameter of the interlayer connection hole 2 is about 0.2 to 0.4 mm.
Reference numeral 3 denotes a thin epoxy resin layer covering the surface of the heat radiation plate 1 including the inner wall surface of the interlayer connection hole 2. here,
The epoxy resin layer 3 is, for example, an epicoat resin, but may contain silica powder or the like, and has a thickness of about 10 to 30 μm. The coating of the epoxy resin layer 3 is formed by, for example, converting epoxy resins into a solution,
This solution is applied and dried, and if necessary, baked.

Reference numeral 4 denotes a conductor plating layer formed on the epoxy resin layer 3 on the inner wall surface of the interlayer connection hole 2 and electrically connecting corresponding wiring patterns (not shown). Here, a conductor plating layer 4 formed on the inner wall surface of the interlayer connection hole 2 with an epoxy resin layer (insulator layer) 3 interposed therebetween.
Are, for example, (a) a chemical plating layer, (b) a multi-layer type of a chemical plating layer and an electroplating layer, and (c) a solder plating layer. And the form of connecting between the wiring pattern layers is as follows:
Connections between the inner wiring pattern layers in the multilayer wiring, via connections as a connection between the inner wiring pattern layer and the outer wiring pattern, and through-hole connections penetrating both sides are exemplified.

Next, a description will be given of an example of manufacturing the surface mounting wiring board having the above configuration.

First, an iron plate having a thickness of about 0.2 mm and a square of 100 × 30 mm was prepared, and a hole of about 0.3 mm penetrating in a thickness direction was formed at a predetermined position by, for example, drilling. The drilled iron plate is coated with an epoxy resin solution prepared in advance and dried to form an epoxy resin layer with a thickness of approximately 50 μm and a uniform thickness on the entire surface including the inner wall surface of the drilled hole. I do.

Thereafter, a pretreatment for chemical plating (for example, an aqueous solution of palladium chloride) is applied to the surface of the epoxy resin layer.
And then immersed in a chemical copper plating solution to a thickness of 5 μm.
A copper layer of a degree is entirely formed. Further, an electrolytic copper plating process is performed using the formed chemical copper plating layer as one electrode, and a copper plating layer is grown thick as a whole.
Next, an etching resist film is formed on the copper plating layers on both the main surfaces, and is sequentially subjected to exposure and development to form an etching resist pattern including the inner wall surface of the perforated hole. With the resist mask applied in this way, the formed and exposed copper plating layer is selectively etched away, so that the wiring pattern layers on both surfaces are formed on the inner wall surface of the drilled hole. A wiring board 5 electrically connected by the layers is obtained.

The wiring board 5 for surface mounting has a structure having a required wiring pattern and a through-hole connection portion while using an iron plate as a support base and a thin epoxy resin layer as an insulator layer. In other words, a structure in which a required wiring pattern is formed on a metal plate surface having good heat dissipation properties is employed as an insulating layer of epoxy resin having high electrical insulation properties. In this configuration, since the epoxy resin layer is set to be relatively thin, the operation and heat generation of the semiconductor element mounted and mounted in the wiring pattern region are caused not only from the surface of the semiconductor element itself but also from the support substrate (metal plate). ) Side, heat is easily dissipated. In the above description, a copper plating layer was grown on both main surfaces of the heat radiating plate 1 and a wiring pattern was formed by photo-etching the copper plating layer. Instead of the copper plating layer, for example, a copper foil having a thickness of 18 μm was laminated. May be adopted.

FIG. 2 is a cross-sectional view showing a main part of a wiring board for surface mounting according to a second embodiment, which is an example of a structure in which heat radiation plates 1 are laminated. That is, the surface mounting wiring board 5a having a configuration similar to that of the surface mounting wiring board 5 according to the first embodiment.
The structure is such that they are aligned with each other and joined and integrated via an adhesive epoxy resin 6. Then, in order to connect the wiring patterns on both main surfaces, a wiring pattern (shown in the drawing) is provided on the inner surface of the interlayer connection hole 2 penetrated in the thickness direction on the surface of the epoxy resin layer 3 and the end surface of the adhesive epoxy resin layer 6. Omitted)
A conductor plating layer 4 for electrically connecting between them is formed.

In the case of the configuration shown in FIG. 2, even if a configuration is adopted in which semiconductor elements are respectively mounted and mounted on the wiring pattern regions on both sides, the operation and heat generation of these semiconductor elements are limited only from the surface of the semiconductor elements themselves. Instead, heat is easily transmitted through the two supporting substrates (metal plates) 1 arranged close to each other, and the heat is quickly radiated.

FIG. 3 is a cross-sectional view showing the structure of a main part of a wiring board for surface mounting according to a third embodiment, in which a heat dissipation plate 1 is laminated on both main surfaces of a resin-based wiring board 7. It is. That is, the glass / epoxy resin-based wiring board 7 is interposed and aligned between the surface-mounting wiring boards 5a having a configuration similar to the surface-mounting wiring board 5 according to the first embodiment, and the adhesive epoxy It has a structure in which it is joined and integrated via the resin 6. In order to connect the wiring patterns on both main surfaces, the surface of the epoxy resin layer 3 on the inner wall surface of the interlayer connection hole 2 penetrated in the thickness direction, the end surface of the glass / epoxy resin wiring board 7 and the adhesive epoxy resin On the end face of the layer 6, a conductor plating layer 4 for electrically connecting wiring patterns (not shown) is formed.

In the case of the configuration shown in FIG. 3, even if a configuration is adopted in which semiconductor elements are respectively mounted and mounted on the wiring pattern areas on both sides, the operation and heat generation of those semiconductor elements are limited only from the surface of the semiconductor elements themselves. Instead, heat is easily transmitted through the two supporting substrates (metal plates) 1 arranged close to each other, and the heat is quickly radiated. That is, by adopting a configuration in which the heat radiating plate 1 is arranged at least at a position (outside) close to the surface on which the semiconductor element or the like is mounted / mounted, the operation / heat generation of the mounted / mounted electronic component is reduced by the heat radiation Heat is easily dissipated through the plate 1. Therefore, the mounted and mounted semiconductor element and the like sufficiently exhibit required performance as an electronic circuit element, and function as a highly reliable mounted circuit device.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention. For example, an aluminum plate may be used in place of the iron plate as the heat dissipating plate, and the thickness of the heat dissipating plate or the like may be reduced to form a multilayer structure.

[0022]

According to the first and second aspects of the present invention, while electrical insulation is ensured by the epoxy resin layer,
Since the heat conductivity and the mechanical strength are maintained by the heat radiating plate, the size and weight of the surface mounting wiring board can be easily reduced. That is, a surface mounting wiring board suitable for a configuration such as a memory module that is compact and maintains and exhibits high performance is provided.

According to the third aspect of the present invention, it is possible to easily provide a low-cost, high-yield mounting wiring board suitable for a configuration such as a memory module which retains and exhibits high performance with a compact size.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a main configuration of a surface mounting wiring board according to a first embodiment.

FIG. 2 is a cross-sectional view illustrating a main configuration of a surface mounting wiring board according to a second embodiment.

FIG. 3 is a sectional view showing a configuration of a main part of a wiring board for surface mounting according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Heat dissipation plate 2 ... Interlayer connection hole 3 ... Epoxy resin layer 4 ... Conductor plating layer 5, 5a ... Surface mounting wiring board 6 ... Adhesive epoxy resin layer 7 ... Glass epoxy resin System wiring board

Claims (3)

[Claims] 1. A heat dissipation plate having an interlayer connection hole penetrating in a thickness direction and connecting between wiring patterns on both main surfaces, and a heat dissipation plate surface including an inner wall surface of the interlayer connection hole. At least a heat-dissipating wiring board having a thin epoxy resin layer to cover, and a conductive plating layer formed on the epoxy resin layer surface of the inner wall surface of the interlayer connection hole and electrically connecting corresponding wiring patterns. A wiring board for surface mounting, comprising a single layer. 2. The surface mounting wiring board according to claim 1, wherein the heat-dissipating wiring board is arranged on an outer layer side. 3. A step of forming a hole for interlayer connection penetrating in a thickness direction of the heat radiation plate, and a step of forming a substantially uniform thickness epoxy resin layer on a surface of the heat radiation plate. Forming an interlayer connection portion and a wiring pattern on the surface of the epoxy resin layer including the inside of the hole for interlayer connection.