JPH0856067A - Circuit device - Google Patents

Abstract

PURPOSE:To improve the reliability of a circuit device including a semiconductor chip while miniaturizing and cutting down the cost thereof. CONSTITUTION:An enclosure body 5 is arranged around a plurality of semiconductor chips 3 on a circuit substrate 1 so as to fix this enclosure body 5 on the substrate 1 using a bonding agent 7. Next, insulator gel 6 is poured in the aperture parts of cylindrical protrusions 13, 14 of the enclosure body 5. At this time, the substrate 1 serves for common use of a circuit formation and the bottom surface of a containing body of the insulator gel 6. In such a constitution, the width of the aperture parts of cylindrical protrusions 13, 14 is narrowly formed so as to protect the insulator gel 6 from running away.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit device such as a voltage adjusting circuit device which requires high reliability.

[0002]

2. Description of the Related Art As a circuit device such as a small switching regulator, there is known a device in which a semiconductor chip, a capacitor chip, etc. are mounted on a circuit board and these are molded with an insulating resin.

This type of resin mold type circuit device has a problem that stress is applied to a semiconductor chip or the like when it is subjected to a heat cycle, resulting in deterioration of characteristics. In order to solve the drawbacks of the resin molding device, there is a technique of surrounding a semiconductor chip with silicone gel.

[0004]

By the way, if each semiconductor chip used in the circuit device is surrounded by silicone gel, the size of the semiconductor element becomes large, and the circuit device becomes large and costly.

Therefore, an object of the present invention is to provide a circuit device which can be miniaturized and reduced in cost and has high reliability.

[0006]

The present invention for achieving the above object provides, in a circuit device having a plurality of electronic components mounted on an insulating circuit board, a gel-like insulator surrounding the plurality of electronic components, An insulating envelope disposed on the substrate so as to surround the gel insulator, the envelope is formed without a bottom, and the lower end of the envelope is fixed to the substrate. , The envelope has at least one tubular protrusion, and the tubular protrusion is capable of injecting the gel-like insulator into the inside of the envelope, but the gel-like insulator is The present invention relates to a circuit device characterized in that it is formed so that it cannot flow out from the inside of an enclosure to the outside.

[0007]

The action and effect of the present invention does not give an excessive stress to electronic parts even if the ambient temperature changes. Therefore, the reliability of the electronic component can be improved. Since the gel insulator does not surround only one electronic component but collectively surrounds a plurality of electronic components, the accommodation structure of the gel insulator can be simplified. Further, in the present invention, since the insulating circuit board is also used as the bottom of the accommodating body of the gel-like insulator, downsizing and cost reduction of the circuit device can be achieved.
Further, in the present invention, since the insulating enclosure is fixed on the circuit board like the electronic component, the gel container can be easily constructed. Further, according to the present invention, the envelope is provided with a cylindrical protrusion having an opening, and the opening can be filled with the gel insulator, but the gel insulator is prevented from flowing out from the inside. Since it is formed so as to be able to prevent it, not only is it easy to inject the gel-like insulator, but it is also possible to prevent the gel-like insulator from flowing out without providing a special lid body. The housing structure of is simplified. 1

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a power supply circuit device according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, the power supply circuit device includes a conductor layer 2, a semiconductor chip 3 as a plurality of electronic components, a capacitor chip (not shown), a thickness on a surface of an insulating circuit board 1 made of ceramic. Membrane resistors (not shown), terminal conductor layers 4 and the like are provided.
Since the present invention can be applied to various circuits and does not have a special feature in the circuit configuration, detailed description of the circuit configuration will be omitted.

For example, a semiconductor chip 3 such as a transistor chip and other electronic parts are surrounded by an insulating enclosure 5 made of synthetic resin, and a gel-like insulator 6 made of silicone gel is housed in the enclosure 5. ing.

The enclosure 5 excludes the terminal conductor layer 4 and includes a plurality of semiconductor chips 3, other electronic components and a wiring conductor layer 2.
Are encircled together. The lower end of the enclosure 5 is fixed to the circuit board 1 with an insulating adhesive 7. Enclosure 5
Are four side surfaces 8, 9, 10, 11 and a top surface 12
And first and second cylindrical protrusions 13 and 14.
The first and second cylindrical protrusions 13 and 14 protrude from the upper surface portion 12. Although the first and second cylindrical protrusions 13 and 14 can be injected into the envelope body 5 of the gel insulator 6,
It is formed so as to prevent the outflow from the inside to the outside. That is, the gel insulator 6 does not flow like an aqueous solution, has viscosity, and has an extremely large surface tension, and therefore does not flow out from a minute gap. Therefore,
The horizontal width W1 and the vertical width W2 of the first tubular protrusion 13;
The horizontal width W3 and the vertical width W4 of the cylindrical protrusion 14 are determined in consideration of the viscosity of the gel insulator 6, and in this embodiment, W1 = 4.
mm, W2 = 13.6 mm, W3 = 5.6 mm, W4 = 13.
It is set to 6 mm, and the height H of these is set to 2.2 mm. The first tubular protrusion 13 is used for degassing when the gel insulator 6 is injected, and the second tubular protrusion 14 is used for the gel insulator 6 injection. 1
The cylindrical protrusion 13 has a smaller opening area than the second cylindrical protrusion 14.

When this circuit device is manufactured, a wiring conductor layer 2 and a terminal conductor layer 4 are provided on a circuit board 1, and a resistor is further provided. Next, the semiconductor chip 3 and other components are prepared. Make the desired circuit connections by mounting electronic components, then
The lower end of the envelope body 5 is fixed to the substrate 1 with an adhesive 7, and then the gel insulator 6 is injected into the envelope body 5 through the opening of the second tubular protrusion 13 under pressure. First and second cylindrical protrusions 1
The openings 3 and 14 are not specially closed, but the gel-like insulator 6 filled therein acts as a closing body. That is, the gel insulator 6 does not flow like an aqueous solution,
Since it has a relatively large viscosity and surface tension, it does not flow out from the narrow openings of the first and second cylindrical protrusions 13 and 14.

This embodiment has the following advantages. (A) Since the plurality of semiconductor chips 3 and the like are collectively enclosed by the bottomless enclosure 5 and the circuit board 1 is also used as the accommodation bottom of the gel insulator 6, the gel insulator has a small size and a simple structure. 6 can be configured. (B) Since the enclosure 5 is configured to be fixed to the adhesive 7 on the circuit board 1, it can be easily attached. (C) The gel insulator 6 can be easily injected by using the narrow cylindrical protrusions 13 and / or 14 as the injection port of the gel insulator 6. At this time, the first and second cylindrical protrusions 1
One of the gel insulator 6 functions as a gas or air vent when the gel insulator 6 is injected.
Can be injected well. (D) Since the gel insulator 6 does not flow out from the narrow cylindrical protrusions 13 and 14, it is not necessary to provide a special lid, and the cost of the device can be reduced.

[0013]

[Modification] The present invention is not limited to the above-described embodiment, but can be modified. For example, the enclosure 5 may not surround all of the plurality of electronic components, but may surround only some of the selected electronic components. Also, do not fill the gel insulator 6 up to the cylindrical protrusions 13 and 14,
You may fill only in the lower side of the upper surface part 12 of the enclosure 5.

[Brief description of drawings]

FIG. 1 is a plan view of a circuit device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a plan view of an enclosure.

4 is a front view of the enclosure of FIG.

5 is a sectional view taken along line BB of FIG.

6 is a cross-sectional view taken along the line CC of FIG.

FIG. 7 is a perspective view showing the circuit device of FIG. 1 with a part thereof cut away.

[Explanation of symbols]

 1 circuit board 3 semiconductor chip 5 enclosure

Claims (1)

[Claims] 1. A circuit device having a plurality of electronic components mounted on an insulating circuit board, wherein a gel-like insulator surrounding the plurality of electronic components and a gel-like insulator surrounding the gel-like insulator are provided on the substrate. And an insulating enclosure that is formed, the enclosure is formed without a bottom, the lower end of the enclosure is fixed to the substrate, the enclosure has at least one tubular protrusion,
The cylindrical protrusion can inject the gel-like insulator into the inside of the envelope, but the gel-like insulator cannot flow out from the inside of the envelope to the outside. A circuit device characterized by being formed.