JPS5826837B2 - Hybrid integrated circuit board and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hybrid integrated circuit board and method of manufacturing the same.

Japanese Patent Publication No. 46-13234 has already proposed a hybrid integrated circuit board in which the surface of an aluminum substrate is anodized.

In such a hybrid integrated circuit board, aluminum oxide (A1203) is formed in a hexagonal honeycomb shape as shown in FIG.
A round hole 1 is left in the center of each hexagon to allow current to flow for anodic oxidation.

Since aluminum is exposed below this hole 1, it is sealed.

The pore sealing treatment is carried out using hot water or steam at about 98°C for about 30 minutes or more at a current density of 1 to 2 A/di, and this hole 1 is filled with aluminum hydroxide (Al(OH)a) to completely seal it. There is.

A hybrid integrated circuit board is provided by adhering a copper foil onto the sealed oxide film with an epoxy resin.

However, in such a hybrid integrated circuit board, due to the difference in thermal expansion coefficient between aluminum and aluminum oxide, when heated to about 200° C., there is a risk that many cracks will occur in the aluminum oxide, leading to poor insulation.

The present invention was made in view of the new disease, and provides a hybrid integrated circuit board and a method for manufacturing the same, which completely eliminates the drawbacks of the prior art.

An embodiment of the present invention will be described in detail below with reference to FIG.

The hybrid integrated circuit board according to the present invention, as shown in FIG. It consists of a sealed aluminum oxide film 4 and a conductive metal foil layer 6 such as copper foil adhered onto the unsealed aluminum oxide film 3 via an adhesive resin layer 5 such as epoxy.

The feature of the present invention is that unsealed aluminum oxide 3 is provided on the main surface of the substrate 2 on which the conductive metal foil layer 6 is provided, and as described above, the anodized pores formed in the unsealed aluminum oxide 3 are removed by thermal expansion. It is used to absorb stress.

Further, the conductive metal foil layer 6 and the aluminum substrate 2 are insulated mainly by the unsealed aluminum oxide film 3, and the holes left by the anodization are filled with the adhesive resin layer 5 for insulation.

With such a structure, the occurrence of cracks can be prevented on the main surface of the substrate 2 provided with the conductive metal foil layer 6, while on the other hand, the opposite main surface of the substrate 2 exposed to the outside is sealed, so cracks may occur, but the manufacturing process becomes hard. Prevents dirt, scratches, and corrosion inside.

Next, the manufacturing method of the present invention will be explained.

First, as shown in FIG. 2A, aluminum oxide films 3 are formed on both main surfaces of an aluminum substrate 2 by anodic oxidation as in the conventional method.

The aluminum oxide film 3 has holes formed by anodic oxidation as shown in FIG.

Subsequently, as shown in FIG. 2B, a copper foil 6 is adhered to the entire surface of the substrate 2 using an adhesive resin layer 5 such as epoxy.

Thereafter, as shown in FIG. 2C, the entire substrate 2 is subjected to the above-described sealing process.

At this time, since the main surface of the substrate 2 provided with the conductive metal thread layer 6 is covered with the conductive metal foil layer 6, only the opposite main surface of the substrate 2 is selectively sealed.

Although the surface of the conductive metal foil layer 6 is slightly oxidized, it is sufficient to slightly etch the surface.

As in the case of tilled soil, the present invention allows one-sided sealing to be carried out easily using only the same components as in the prior art, without using any masking means.

The copper foil is then etched using well known printed circuit board techniques to form the desired conductive paths.

As described in detail above, the present invention is extremely advantageous since it is possible to realize a hybrid integrated circuit board with fewer cracks, and it can be provided by an extremely easy manufacturing method.

[Brief explanation of the drawing]

FIG. 1 is a top view illustrating the anodized surface of an aluminum substrate, and FIG. 2 is a top view illustrating the present invention. 1 is a hole, 2 is an aluminum substrate, 3 is an unsealed aluminum oxide film, 4 is a sealed aluminum oxide film, 5 is an adhesive resin layer, and 6 is a conductive metal foil layer.

Claims (1)

[Scope of Claims] 1. An aluminum substrate, an unsealed oxide film formed on one main surface of the substrate, a sealed oxide film formed on the opposite main surface of the substrate, and an unsealed oxide film formed on the opposite main surface of the substrate. 1. A hybrid integrated circuit board comprising: a conductive metal foil layer provided on an oxide film via an adhesive resin layer; and the unsealed pores are filled with the adhesive resin layer. 2 Form an oxide film on both main surfaces of an aluminum substrate by anodic oxidation, adhere a conductive metal foil layer to one main surface of the substrate via an adhesive resin layer, and use the conductive metal foil layer as a mask to remove the oxide film. A method for manufacturing a hybrid integrated circuit board, characterized by performing a sealing process.