JPS6311733Y2 - - Google Patents

Description

[Detailed explanation of the idea] (b) Industrial application fields The present invention relates to a sealing structure for a hybrid integrated circuit.

(b) Prior Art As shown in FIG. 1, the conventional hybrid integrated circuit sealing structure consists of a hybrid integrated circuit board on which a power transistor 5 is attached on desired circuit elements such as a chip capacitor 2, a monolithic integrated circuit 3, and a heat sink 4. A sealing lid 7 was adhered to the peripheral edge of 1 with an adhesive sheet 6 to seal it. The external lead 8 is surrounded by a resin filling frame 9 of the sealing lid 7, and is filled with a hard epoxy resin 10 to mechanically reinforce the external lead 8. Note that the resin filling frame 9 has an inclined portion 1 so that the thickness of the resin 10 to be filled becomes thinner as it goes in the depth direction.
1 is provided to prevent adverse effects caused by thermal expansion of the resin 10.

However, recently, as shown in Fig. 2, the external lead 8
There has been a demand for a hybrid integrated circuit with a two-stage structure. In such a hybrid integrated circuit, the resin filling frame 9 of the sealing lid 7 that surrounds the external leads 8 is formed to be considerably thicker than the portion that covers the circuit elements, so the above-mentioned inclined portion 11 alone is insufficient to fill the hard epoxy resin 10. The thickness increased and the thermal expansion of the resin caused an adverse effect. That is, the electrode to which the external lead 8 is fixed by the resin 10 is peeled off from the substrate 1.

(c) Purpose of the invention The present invention has been made in view of the above, and its purpose is to realize a sealing structure for a hybrid integrated circuit that completely eliminates the drawbacks of the conventional technology.

(D) Structure of the Invention The hybrid integrated circuit sealing structure of the invention is, as shown in FIG. 3, a hybrid integrated circuit substrate 21, a circuit element attached to the substrate 21, a sealing cover 27 that abuts against the peripheral edge of the substrate 21, external leads 28 provided on the peripheral edge of the substrate 21, and a resin filling frame 29 of the sealing cover 27 that surrounds the external leads 28. A protrusion 32 is provided to reduce the thickness of the resin filling frame 29 at the depth, and a hard resin 3 is filled up to the fixing portion of the external leads 28 of the resin filling frame 29.
0 and the remainder is filled with soft resin 31.

(E) Example A conductive path (not shown) having a desired pattern is provided on a hybrid integrated circuit board 21 made of aluminum, ceramics, etc. with good thermal conductivity, and desired circuit elements such as a chip capacitor 22, a monolithic A power transistor 25 is attached via an integrated circuit 23 and a heat sink 24.

The sealing lid 27 is made of thermoplastic resin such as Tetoron type.
Use pre-shaped FRPET (product name). The end of the sealing lid 27 comes into contact with the peripheral edge of the substrate 21 and is bonded with the adhesive sheet 26 . A resin filling frame 29 is provided on one side of the sealing lid 27 provided with the external leads 28, and surrounds the external leads 28 with the substrate 21. The external leads 28 have a two-tiered structure with different heights, and the resin filling frame 29 is also formed to be thicker and protrude from other parts that seal the circuit elements.

The feature of the present invention lies in the shape of the resin filling frame 29 of the sealing lid 27. That is, the deep portion of the resin filling frame 29 is provided with a convex portion 32 in order to make the thickness of the filled resin as thin as possible. It is desirable that the thickness of the resin filled in the deep portion of the convex portion 32 be the same as or less than the conventional thickness. This resin filling frame 29 is first filled with a hard epoxy resin 30 up to at least the portions where the external leads 28 are fixed to the substrate 21, thereby mechanically reinforcing the portions where the external leads 28 are fixed. Next, the remaining resin filling frame 29 is filled with a flexible silicone resin 31.

According to the above sealing structure, the epoxy resin 30, which tends to be adversely affected by thermal expansion, is filled to a minimum and its thickness is regulated by the convex portion 32, and the outside, which is required to be moisture resistant, is heated. Since it is filled with soft silicone resin 31 that is not affected by expansion, it is possible to reinforce the two-tiered external lead 28 without sacrificing sealing performance.

(F) Effects According to the present invention, mechanical reinforcement of the external lead 28 having a multi-stage structure can be easily achieved by simply improving the resin filling frame 29 of the sealing lid 27 and the filling resins 30 and 31, and the moisture resistance is improved. A good sealing structure of a hybrid integrated circuit can be achieved.

Further, since the sealing lid 27, which is simple for sealing, can be applied to the multi-stage external leads 28, it is possible to realize mass production and cost reduction of this type of hybrid integrated circuit.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views for explaining a conventional example, and FIG. 3 is a cross-sectional view for explaining the present invention. Explanation of main drawing numbers, 21 is a hybrid integrated circuit board, 2
7 is a sealing lid, 28 is an external lead, 29 is a resin filling frame, 30 is a hard resin, and 31 is a soft resin.

Claims (1)

[Scope of utility model registration request] A hybrid integrated circuit board, a circuit element attached to the board, a sealing lid abutting the peripheral edge of the substrate, an external lead provided on the peripheral edge of the substrate, and the sealing provided to surround the external lead. A resin filling frame of the lid is provided, a convex portion is provided to reduce the depth and thickness of the resin filling frame, and the hard resin is filled up to the fixed part of the external lead, and the remaining resin filling frame is filled with a soft resin. A sealed structure of a hybrid integrated circuit consisting of filling.