JPS5879793A - Hybrid integrated circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to hybrid integrated circuits, and particularly to hybrid integrated circuit boards that require heat dissipation effects.

Conventional hybrid integrated circuits are formed by appropriately attaching passive circuit elements such as resistors and capacitors and active circuit elements such as transistors to an insulating substrate such as a ceramic plate or a glass plate.

However, in the above configuration, the substrate is ceramic.

Because it is an insulating material such as glass, it has poor heat dissipation, and when resistors and transistors designed for high power are installed, the heat generated by these resistors and transistors is significant, causing damage to surrounding areas such as capacitors. There is a risk that not only the components but also the resistors and trunk stars themselves will be destroyed, and even if they are not destroyed, their electrical characteristics will often change significantly.

In addition, in order to effectively dissipate heat, an aluminum metal plate is used, and the entire surface of the aluminum plate is anodized to form an aluminum oxide film, which is used as an insulating substrate. However, in this case, the aluminum oxide film is very sensitive to heat and cracks at about 120°C, and cracks occur even at a temperature difference of 110°C, so the electrical insulation properties are a major problem.

As a measure to improve this electrical insulation, some have coated the aluminum oxide film with a resin, but this has the disadvantage that the resin layer deteriorates heat dissipation. Insulating substrates are also used in which a resin layer is directly provided on the surface of an aluminum plate, but due to problems with pinholes in the resin layer and electrical insulation, the resin layer becomes thick and has very poor heat dissipation. The result is getting worse. As described above, it is unsuitable for use as a circuit board for a hybrid integrated circuit in which circuit elements that consume large amounts of power and generate a large amount of heat must be frequently incorporated, and have many disadvantages.

The present invention solves the above-mentioned drawbacks by providing a hybrid integrated circuit board that effectively radiates heat generated from resistors and transistors, has good electrical insulation, has a simple structure, and can be mass-produced. It is.

The structure of the hybrid integrated circuit board of the present invention is such that a treatment agent in which silicon oxide is stably dispersed in a phenol made of silicone resin and a solvent is applied and hardened on at least the entire surface of the aluminum plate 1 (so-called Dow Corning's best method). Vesta treatment using a processing agent) An insulating film 2 is formed, and a conductive material is selectively deposited on the film 2 to form a plurality of circuit elements such as conductors 3 and 4 and resistors 5 and 6. The hybrid integrated circuit board of the present invention constructed in this way is heat resistant because it is coated with a PESTA treatment agent in which silicon oxide is stably dispersed in a phenol made of silicone resin and a solvent. It has very good properties, and while the conventionally used aluminum oxide film only cracks when heated to about 120°C, it only cracks when heated to 350°C.
No film cracking occurs even after heating for several minutes. Thermal shock resistance is also extremely high; with conventional aluminum oxide film alone, film cracking occurs at a temperature difference of approximately 110°C, but at 300°C.
Even if the film is heated for 1.0 minutes and then immediately immersed in water at 20°C, no film cracking occurs. In addition, it can be applied using any method such as dip method, spray method, or electrostatic coating method, and almost no pinholes are observed.
Shows extremely high corrosion resistance. Furthermore, even when immersed in boiling water for about 500 hours, no blackening occurs, and it exhibits excellent hot water resistance.

When applied by the dip method, the film produced by Vesta treatment is 1
A film thickness of 4 to 6 μm can be obtained in one treatment, and multiple coatings are also possible. In this way, there are no pinholes and the film is thin, so the heat generated by the resistor or transistor itself is quickly transmitted to the aluminum plate through the film and dissipated into the outside air.

In this way, the hybrid integrated circuit board of the present invention is made by performing Besta treatment on the entire surface of an aluminum plate to obtain an insulating film, and then forming circuit elements on the insulating film, and this structure is extremely simple. Moreover, it can be easily and thinly formed with a uniform thickness. In addition, there are no pinholes in the film, and it can be painted with blood, so it has very good electrical insulation properties.The thickness of the layered film is only about 10 μm, so heat from resistors and transistors can be quickly dissipated from the aluminum plate. It can be transmitted to the outside air from the aluminum plate and can be advantageously used as a circuit board of a hybrid integrated circuit designed for high power.

Examples of the present invention will be described below.

(Example) The aluminum plate 1 has a thickness of 2.0 mm and a length of 6.0 cm.
A piece with a width of 4.0 mm was used. Aluminum plate 1
After degreasing with acetone, it was immersed in a 10% sodium hydroxide solution for 3 minutes. Wash this with pure water, and then add it to concentrated nitric acid.
After being immersed for a minute, it was thoroughly washed with pure water and dried. Next, it was applied by a dipping method using Dow Corning's Vesta treatment agent, and cured at 150° C. for 30 minutes to form a Pesta treatment film (diameter: approximately 5 μm). After that, the conductor 3゜4f: is formed on the predetermined mother turn by a vapor deposition method (the conductor weight 1 material is nickel-based), the copper heat sink 7 is fixed to the transistor fixing part of the conductor, the transistor is attached, and the capacitor is A hybrid integrated circuit board could be obtained by attaching peripheral parts such as a resistor and resistors 5 and 6.

In addition, as a conductor formation method, before applying and curing the PESTA treatment agent, it is also possible to laminate copper foil, etc., cure it, then etch the copper foil into a predetermined pattern, and then perform nickel plating, etc. A hybrid integrated circuit board of the present invention is obtained.

FIG. 3 shows the heat dissipation characteristics of the hybrid integrated circuit board according to the present invention.

A is a paper phenol board, B is a glass epoxy board, C is a ceramic board, D is a conventional aluminum board, and E is a hybrid integrated circuit board of the present invention.

It effectively dissipates the heat generated from resistors and transistors, has good electrical insulation, has a simple structure, is suitable for mass production, and has practical value.

[Brief explanation of the drawing]

1 and 2 are diagrams showing the entire hybrid integrated circuit board used in an embodiment of the present invention, with FIG. 1 being a plan view and FIG. 2 being a sectional view. FIG. 3 is a diagram showing the heat dissipation characteristics of various substrates. DESCRIPTION OF SYMBOLS 1... Aluminum plate, 2... Insulating film by PESTA treatment, 3, 4... Conductor, 5, 6... Resistor, 7
··heat sink. Figure 1 Figure 2

Claims (1)

[Claims] A treatment agent in which silicon oxide is stably dispersed in a varnish made of silicone resin and a solvent is applied to at least the entire surface of the aluminum plate and cured to form an insulating film, and a conductive material is selectively applied on the film. A hybrid integrated circuit board characterized in that a plurality of circuit elements are mounted after being adhered.