JPS63293958A - Electronic device - Google Patents

Abstract

PURPOSE:To obtain the sufficient adhesive strength of a cap by arranging and recessing an annular groove inside an adhesive material layer in a mating face with the cap for a sleeve surrounding a resin. CONSTITUTION:To enclose a second resin layer 10 by a sleeve 11 in a high-frequency power module 1, the sleeve 11 is disposed onto a heat sink 2 so as to surround a pellet 6 and a wiring board 4, and an silicone resin gel forming the resin layer 10 is potted into the sleeve 22 from an opening 12. The resin is baked and deaerated. The resin gel is sucked up to the top face of the opening 12 from the opening 12 at that time, but a portion of the gel 10a carried into an annular groove 13 recessed so as to surround the opening 12 in the top face of the sleeve 11 is not diffused outside the annular groove 13 on the top face of the sleeve. Accordingly, an adhesive material layer 15 is not disturbed by the resin gel 10a, and properly displays adhesion and strongly fixes a cap 16 to the sleeve 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to electronic devices, and in particular to pancasing technology, such as hybrid integrated circuit devices (hereinafter referred to as , called a high frequency power module.

) and related to infants.

[Conventional technology]

As a high-frequency power module, the resin that non-hermetically seals the element is made of gel-like resin, and this gel-like resin is covered with a sleeve and a cap that is placed over the sleeve and fixed with an adhesive layer. There are some that come with different packages.

An example of such a puff caging technique is "Nikkei Electronics Special Issue Yacro Devices Volume 2" published by Nikkei McGraw-Hill, June 11, 1980, pages 160 to 168.

[Problem that the invention seeks to solve]

In a high-frequency power module equipped with a package with such a structure, during baking or foaming treatment, gel-like +J (grease) is sucked up from the opening of the sleeve to the mating surface with the socket, and the resin increases the adhesive strength. In order to weaken
The inventor of the present invention has revealed that there is a problem in that the adhesive strength of the cap is insufficient.

An object of the present invention is to provide a pancaging technique that provides sufficient strength.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means for solving problems]

An overview of typical inventions disclosed in this application is as follows.

That is, an annular groove is disposed inside the adhesive layer and recessed in the surface of the sleeve surrounding the resin that is mated to the cap.

[Effect]

According to the above-mentioned means, even if gel-like resin is sucked up from the opening of the sleeve onto the surface mating with the cap during baking treatment or defoaming treatment, it will not be absorbed inside the adhesive layer on the surface of the sleeve mating with the cap. The annular groove provided blocks the resin that has sucked up, so the resin does not reach the adhesive layer area. Therefore, the adhesive can be attached to the cap with the desired adhesive force without being hindered by the resin. It will be glued to the sleeve.

〔Example〕

FIG. 1 is a longitudinal sectional view showing a high frequency power module according to an embodiment of the present invention, FIG. 2 is a plan view showing the state with the cap removed, and FIG. 3 is a bottom view showing the cap.

In this embodiment, this high frequency power module l is equipped with a heat sink (base) 2, and the heat sink 2 is made of a conductive material with good thermal conductivity such as copper, and is formed by an appropriate means such as press working or the like. It is formed into a substantially rectangular plate shape. On the main surface (hereinafter referred to as the top surface) of the heat sink 2, a wiring board 4 made of an insulating substrate using alumina or the like is arranged approximately at the center and fixed with an adhesive layer 3. Electric wiring 5 is formed thereon using a conductive material. A pellet 6 is arranged at a predetermined position on the wiring board 4 and bonded by a suitable means (not shown) such as adhesion using a conductive fIi adhesive, and the pellet 6 is attached to a bonding wire 7. It is electrically connected to the electrical wiring 5 and electrically led out to the outside via an outer lead 8.

A first resin [9] made of a resin such as a phenolic resin (chip coat resin) is formed on the pellet 6 and the bonding wire 7 by an appropriate molding method such as botting, thereby forming a pellet. 6 and bonding wire 7 are non-hermetically sealed. Furthermore, a second resin layer 10 made of a resin that maintains a gel state and has flexibility, such as silicone gel resin, is formed on the first resin layer 9 and the wiring board 4. Layer IO is surrounded by sleeve 11.

The sleeve 11 is integrally molded from hard resin into a hollow, substantially rectangular parallelepiped with one side open by a suitable means such as injection molding. It is formed into a similar shape that is smaller than the actual shape.

An annular groove 1 for gel-like resin damming is provided on the upper surface of the sleeve 11.
3 and an annular groove 14 for adhesive damming are arranged inside and outside at appropriate intervals, and are recessed in a substantially rectangular ring shape similar to the opening 12, and both grooves 13
．． 14 has a substantially square cross-sectional shape, and its depth and width are set to dimensions that allow it to perform the gel resin damming function and the adhesive damming function, which will be described later.

Here, in order to surround the second resin layer IO with the sleeve 11, first, the sleeve 11 is fixedly disposed on the heat sink 2 so as to surround the pellet 6 and the wiring board 4, and then the second resin layer 10 is An appropriate amount of silicone-based gel-like cedar lubricant for forming the sleeve is potted into the sleeve 11 through the opening 12.

Thereafter, the botted gel-like resin is subjected to a haking process and a foaming process. At this time, the gel-like resin is sucked up from the opening 12 of the sleeve 11 to its ball surface, but the sucked up resin flows into the annular groove 13 sunk in the upper surface of the sleeve 11 so as to surround the opening 12. 10a does not diffuse outward from the annular groove 13 on the upper surface of the sleeve. In other words, the annular groove 13 functions to dam up the resin 10a that has been sucked up.
This prevents the absorbed resin 10a from adhering to the upper surface of the sleeve 11.

A cap 16 is placed on the sleeve 11.
1, and is fixed by an adhesive layer 15 made of a material having sealing properties such as a silicone rubber adhesive. The cap 16 is made of the same material as the sleeve 11 and is integrally molded into a flat plate shape that is approximately the same as the upper surface of the sleeve 11 by a suitable means such as injection molding.
A protrusion 17 is formed in a substantially rectangular ring shape and protrudes from the outer periphery of the contact surface with the sleeve 11, and the protrusion 17 is fitted into the outer annular groove 14° of the sleeve 11. Furthermore, a pair of locking pawls 18 are arranged symmetrically on the inside of the protruding portion 17 of the cap 11 and protrude downward. Each is locked.

Here, when the cap 16 is attached onto the sleeve 11, first, the adhesive for forming the adhesive layer 15 is applied to the sleeve 1 after being subjected to the necessary pretreatment as described above.
1 is applied between the inner and outer annular grooves 13 and 14 on the upper surface. Next, both locking claws 1 are inserted so that the cap 16 is placed on the sleeve 11 and the protrusion 17 is fitted into the outer annular groove 14.
8 are fitted over the lower edges of the openings 12 so as to engage with each other. The cap 16 is positioned on the sleeve 11 by fitting the protrusion 17 and the annular tR14, and the cap 16 is prevented from being removed from the sleeve 11 by the engagement of the locking claw 18 with the opening edge.

When the cap 16 is pressed onto the sleeve 11, the adhesive applied to the upper surface of the sleeve protrudes inward and outward, but since the annular grooves 13 and 14 are recessed on both sides of the applied surface, The adhesive does not spread inwardly and outwardly, especially if the adhesive spreads outwardly.
It is necessary to prevent the adhesive from spreading, since the appearance of the adhesive will be impaired if it is exposed on the side surface of the adhesive.

By the way, the adhesive layer 1 of the cap 16 to the sleeve 11
In the formation of step 5, if the gel-like resin 10a sucked up to the upper surface of the sleeve 11 adheres to the adhesive coated surface of the upper surface of the sleeve as described above, the adhered resin will prevent proper formation of the adhesive layer. , the adhesive force of the adhesive layer 15 is weakened.

If the adhesive force of the adhesive [15 is weakened, the cap 16 will be easily peeled off from the sleeve 11, which will reduce the quality and reliability of the product.

However, in this embodiment, as described above, the gel-like resin 10a sucked up onto the upper surface of the sleeve 11 is removed from the annular groove 1.
3 and is prevented from spreading outward beyond that point, the adhesive rM15 is dammed by the gel-like resin tO.
(a), the cap 16 is strongly fixed to the sleeve 11 by properly exerting adhesive force.

In this way, the puff cage 19 for sealing the electrical wiring 5, pellet 6, bonding wire 7, etc.
1st non-hermetically sealed. a second resin layer 9.10, and a second resin layer 9.10;
A sleeve 11 surrounding the outside of the resin layer 10 and a cap 1
6. It will be composed of a heat sink 2.

According to the embodiment described above, the following effects can be obtained.

(11 By embedding an annular groove inside the adhesive layer of the mating surface of the sleeve with the cap, it is possible to prevent the gel-like resin sucked up to the mating surface from spreading outward by the annular groove. Therefore, regardless of the absorption of the gel-like resin, it is possible to prevent a decrease in the bonding force between the sleeve and the cap due to the adhesive layer, and it is possible to firmly fix the cap to the sleeve.

(2) Since the cap can be firmly fixed to the sleeve regardless of whether the gel resin is sucked up, the use of the gel resin can be ensured, and the work and conditions for processing the gel resin can be improved. It can be left unchanged or relaxed.

(3) By ensuring the use of gel-like resin and increasing the adhesive strength between the cap and sleeve, it is possible to completely prevent moisture from entering the puff cage and improve moisture resistance. It is possible to prevent problems such as corrosion and poor insulation, and improve product quality and reliability.

(4) By embedding an annular groove on the outside of the adhesive layer of the sleeve, the annular groove can prevent the adhesive from protruding to the outside of the sleeve, thereby preventing deterioration in the appearance of the package. can.

Although the invention made by the present inventor has been specifically explained based on Examples above, the present invention is not limited to the above Examples, and it is possible to make various changes without departing from the gist of the invention. Not even.

For example, the annular groove disposed inside the adhesive layer is not limited to a square cross-section, but may also be formed in a figure-7 shape, a semicircular shape, etc. It is desirable that the depth (depth) be appropriately selected in accordance with various conditions such as the situation in which the gel-like resin is sucked up and the correlation between the size of the bonding margin and the like.

The outer annular groove of the sleeve, the protrusion of the cap, and the locking pawl may be omitted.

The sleeve and the cap are not limited to being made of resin, but may be made of metal or the like.

The above explanation has mainly been about the case where the invention made by the present inventor is applied to high frequency power modules, which is the background application field, but it is not limited to this, and the invention can also be applied to hybrid ICs, etc. Therefore, at least the present invention can be applied to all electronic devices equipped with a package in which resin is covered with a sleeve and a cap.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

By placing an annular groove inside the adhesive layer on the mating surface of the sleeve with the cap, the sleeve and cap can be bonded together regardless of the gel-like resin being sucked up to the top surface of the sleeve. Since strength can be increased, product quality and reliability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a high frequency power module according to an embodiment of the present invention, FIG. 2 is a plan view showing the state with the cap removed, and FIG. 3 is a bottom view showing the cap. ■... High frequency power module, 2... Heat sink, 3... Adhesive layer, 4... Wiring board, 5... Electric wiring, 6... Pellet, 7... Bonding wire, 8 ... Outer lead, 9... First resin layer, 10.
... second resin layer (gel-like resin layer), 11 ... sleeve, 12 ... opening, 13 ... annular groove for resin damming,
14... Annular groove for adhesive damming, 15... Adhesive layer, 16... Cap, 17... Projection, 18...
-Latching claw, 19...Package. ／□）

Claims (1)

[Claims] 1. An electronic device comprising a sleeve surrounding a non-hermetically sealed resin and a cap placed over the sleeve so as to close the opening thereof and fixed by an adhesive layer. 1. An electronic device, characterized in that an annular groove is disposed inside the adhesive layer and recessed in the surface of the sleeve mating with the cap. 2. The electronic device according to claim 1, wherein the annular groove is also arranged and recessed outside the adhesive layer. 3. The electronic device according to claim 1, wherein a gel-like resin is used as the non-hermetic sealing resin.