JPH0231794Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hybrid integrated circuit with an improved degree of integration.

[Conventional technology]

Hybrid integrated circuits (hereinafter referred to as HICs), in which wiring patterns and resistors are printed on a ceramic substrate using thick-film printing technology, and electronic components such as transistors, capacitors, and semiconductor integrated circuits that cannot be printed are mounted by soldering, are: It is mounted in electronic equipment as one electronic component. Since the mounting space for small devices such as in-vehicle equipment is limited, HICs with a higher degree of integration are required.

Figure 3 shows the conventional single-in-line (SIL) type
Figure 4 is a side view of the dual-in-line (DIL) type HIC. In the figure, 1 is a ceramic substrate, on one side of which wiring patterns and resistors (none of which are shown) are printed using thick film printing technology. Reference numeral 2 denotes electronic components such as transistors and semiconductor integrated circuits, which are fixed by reflow soldering to the surface of the substrate 1 on which the wiring pattern is formed. Reference numeral 3 denotes an external terminal, which is fixed to the side of the substrate 1 with solder 4 and connected to a required conductive pattern. The HIC in which this external terminal 3 is provided only on one side of the board 1 is shown in Figure 3.
The HIC installed on both sides of the SIL type is the DIL type shown in Figure 4. The SIL type is mounted on a printed wiring board (not shown) with the board 1 standing upright, and the DIL type is mounted with the board 1 horizontal.

The number of elements mounted on this type of HIC is limited by the area of the ceramic substrate used, and there is a certain limit to the degree of integration. Therefore, attempts have been made to double the degree of integration by using the front and back surfaces of a single ceramic substrate. However, for this purpose, through-hole manufacturing technology is needed to partially connect the conductive patterns on the front and back sides, and in order to solder electronic components on both sides at the same time, the electronic components on the back side are temporarily attached to the board surface with adhesive in advance. It is necessary to use a vapor flow method in which reflow solder is heated and solidified in a high-temperature inert gas, making the manufacturing process complicated and sophisticated. This has the disadvantage of increasing the probability of producing defective products.

Therefore, as shown in Japanese Utility Model Application Laid-Open No. 55-84980, as a structure for improving the degree of integration with a simple structure, components are soldered to one side of each of two boards and the other sides are bonded together. It is known that it is integrated.

[Problem that the invention attempts to solve]

However, in such prior art, the electrical connection between the two boards is made through through holes, so when this is applied to a ceramic board, it is necessary to employ through hole manufacturing technology, which increases the complexity and sophistication of the manufacturing process as described above. However, it is not possible to solve the problems of increasing the probability of defective products.

The present invention aims to increase the degree of integration of a single HIC through the simple process of bonding two ceramic substrates together, and to realize electrical connection between the two ceramic substrates with a simple configuration.

[Means for solving problems]

The hybrid integrated circuit of the present invention is produced by forming a wiring pattern on each side of two ceramic substrates, soldering the necessary electronic components, and bonding the other surfaces of the two ceramic substrates together to integrate them. Furthermore, an external terminal is provided which is commonly connected to the wiring patterns of both substrates so as to sandwich the ends of both substrates.

[Effect]

A conductive pattern is formed on one surface of each ceramic substrate in advance, and electronic components are soldered to that surface.
The technique of manufacturing one HIC by bonding the unused surfaces of two such substrates together is easy to manufacture because it simply requires an additional bonding process, and the probability of producing defective products is low.

Furthermore, since the external terminals are commonly connected to the wiring patterns of both substrates, electrical connection between both substrates can be achieved simultaneously by attaching the external terminals to the substrates.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 is an explanatory diagram of the manufacturing process order showing one embodiment of the present invention, where 1 and 1' are two independent ceramic substrates, and 2 and 2' are mounted on their conductive patterned surfaces by reflow soldering. 3 is an external terminal, and 4 is solder. A shows a state in which electronic components 2 and 2' are mounted on ceramic substrates 1 and 1', with the unused surfaces on which no electronic components are mounted facing each other. From this state, the two unused surfaces are bonded with adhesive, and the two substrates 1 and 1' are bonded together as shown in Figure b.
to integrate. The adhesive used at this time is, for example, a highly thermally conductive adhesive (trade name: Lambdite, manufactured by Denki Kagaku Kogyo) containing an epoxy resin as its main ingredient. b
If the substrates 1 and 1' are integrated as in
It has the same degree of integration as a single ceramic substrate with conductive patterns formed on both sides and electronic components mounted thereon. In terms of thickness, even if the number of ceramic substrates increases by one, the increase is only 0.635 mm if the thickness is standard, and if one with half this thickness is used, there will be no increase at all. After bonding in this manner, terminals 3 are attached and soldered to sandwich the ends of both substrates 1 and 1'. c and d
are the front view and end view of the SIL type, and e is the front view and end view of the SIL type.
FIG. 3 is a side view of the DIL type. At this time, the terminal 3 may be connected to a conductive pattern on one of the substrates 1, 1', or may be connected to a conductive pattern on both substrates such as a through hole.

Figures 2a to 2c are block diagrams showing other embodiments of the present invention, in which copper is placed between ceramic substrates 1 and 1'.
The first point is that a heat sink 5 made of aluminum or the like is interposed.
Different from the illustration. Figures 2a and b show the SIL type; a is a type in which the upper end of the heat sink 5 is bent to transfer heat to the top cover of the equipment; It is something that heats up. Further, c is a DIL type and has a screw hole 6 similar to b. The same adhesive as shown in FIG. 1 can be used to bond the heat sink 5 and the ceramic substrates 1, 1'. By interposing the heat radiating plate 5 in this manner, even if there is a heat generating element such as a power transistor in the mounted electronic components 2, 2', the heat can be effectively radiated.

[Effect of idea]

As described above, according to the present invention, it is possible to double the integration density of a hybrid integrated circuit by simply adding the simple process of bonding ceramic substrates together, and it is possible to double the integration density of a hybrid integrated circuit by simply adding the simple process of attaching external terminals to the substrate. It is possible to electrically connect the substrates.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing one embodiment of the present invention;
This figure is a block diagram showing another embodiment of the present invention, and FIGS. 3 and 4 are block diagrams showing different examples of conventional hybrid integrated circuits. In the figure, 1 and 1' are ceramic substrates, 2 and 2' are electronic components, and 3 is an external terminal.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A wiring pattern is formed on each side of two ceramic substrates and necessary electronic components are soldered thereto, and the other surfaces of the two ceramic substrates are bonded together. A hybrid integrated circuit characterized by being integrated and further provided with external terminals commonly connected to the wiring patterns of both substrates so as to sandwich the ends of both substrates. (2) The hybrid integrated circuit according to claim 1, wherein the two ceramic substrates are bonded together via a metal plate.