JPS5839039A - Resin-sealed semiconductor device - Google Patents

Abstract

PURPOSE:To improve the reliability such as moisture resistance and pressure crack resistance of a resin-sealed semiconductor device by resin-sealing the opening of a case corresponding to the periphery of the side of an element to be sealed in temporarily blocked state and adhering between metallic substrates and resin case, thereby preventing transmission of moisture and gas impurity. CONSTITUTION:Three diode elements 12 and terminal 13 are formed on a common metallic substrate 11, and a hole is formed at the portion corresponding to the periphery of the side of the elements 12 at the resin case 14 so as not to contact directly with the substrate 11, and silicon tape is temporarily bonded to the corresponding part or an exclusive jig is prepared to temporarily block it. Then, thermosetting liquid epoxy resin 16 is filled, a resin cover 11 is covered, the resin is hardened, and the jig is removed, thereby completing the desired product.

Description

[Detailed description of the invention] This invention relates to a resin-sealed semiconductor device fK.

As a conventional resin-sealed semiconductor device of this type, the structure of a diode module in which three diode elements are soldered to a metal substrate, a case is fitted and resin-sealed is shown in FIGS. 1 to 3. It is. That is, in each of these figures, three diode elements (resistances) are soldered to a common metal substrate (1), and terminals (3) are uniformly connected to each element (2). The resin case (4) encloses each element (2) and is placed on the metal substrate (1) with a part of each terminal (3) protruding upward. Glue it with double-sided adhesive tape or silicone rubber adhesive (5) K.Furthermore, inject thermosetting liquid epoxy resin into the resin case (4) and attach it to the resin lid (7) that will become the terminal block.
is inserted onto the case from above each terminal (3), and then the temperature is raised to about 120 to 130°C for 4 to 5 hours! Then, the injected resin is cured and completed.

and y to match the expansion coefficient of the liquid epoxy resin silicon chip and the metal substrate filled in the resin case (4), and to ambiguous the adhesive force between the diode element (2) and the metal substrate (1), The K-bond was selected to prevent moisture from penetrating from the outside, but on the other hand, the metal substrate (1) and the resin case (4) were made using double-sided adhesive tape with a rough structure (degree of polymerization). Ike silicone rubber adhesive (5)
Due to the bonding, the bonded surface is easily permeable to moisture and gaseous impurities.When this is tested for moisture resistance, this bonded area, indicated by the symbol (at), is easily permeable to moisture and gaseous impurities within a few hours. Permeation is allowed, and after that, the penetration is blocked by the resin adhesion force of the part shown by the symbol (b) from the coexisting floor part to the element brazing part.However, conventionally, this blocking power is exerted (b) Moisture resistant due to its short dimensions.

There was a problem with the reliability of the pressure sagging resistance, and in order to improve this reliability, it was necessary to take measures by increasing the dimensions (b) and, ultimately, the external dimensions.

In view of the above-mentioned conventional circumstances, the present invention aims to improve the reliability of moisture resistance and pressure resistance by improving the bonding means between the metal substrate and the resin case.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 4 to 7.

In the embodiments shown in FIGS. 4 to 7 as well, three diode elements C12] are provided on a common metal substrate (11), and terminals (13) are taken out from each element (12), and a resin In the case C14), the part corresponding to the side of each element Cl2) is set as an opening (14m) and the substrate C
11) Do not touch the resin case C directly.
14) at the farthest end other than the periphery of the side of the element, use a clip, screw, etc. to hold it lightly (pressed) to the extent that it does not shift, and color-layer each element (12) in the same way, and The corresponding part (14m) is temporarily closed by attaching silicone tape C15) or by preparing a special jig. Next, in the same way as above, thermosetting liquid epoxy resin C1@) was injected into the resin case (4), and resin 7C17), which would become the terminal block, was applied first.
The temperature is raised to about 120-130° C., and the injected resin is left to stand for 4-5 hours to harden. After waiting for this hardening, the silicone tape (15) is peeled off or the jig is removed to complete the process.

In this case as well, the injection resin should be a material that matches the expansion coefficient of the silicon chip and the metal substrate, protects the soldered diode element, and can bond the metal substrate (11) and the resin case C14). In the configuration of this embodiment, the distance (a) corresponding to the bonded portion between the metal substrate (1) and the resin case (4) in the conventional example is at least 4, that is, (a + b) = =a
(The bonding distance can be shortened by cl, and the reliability can be improved by e/1 times.

Note that although the above embodiment is applied to a diode element, it goes without saying that it can also be applied to other semiconductor elements.

As described in detail above, according to the present invention, a resin case is used with the case portion corresponding to the periphery of the side part of the element to be sealed as an opening, and the resin case is placed on a metal substrate to which the element is fixed. The case is held at the end farthest from the element so that it does not shift, and the opening is temporarily closed and sealed with a resin. By adhering between the substrate and the resin case, the adhesion distance from the element to the outside can be significantly shortened, and the penetration of moisture and gaseous impurities is more effectively prevented, resulting in moisture resistance and corrosion resistance. It is possible to greatly improve the reliability such as traction performance4, and for this reason, it is possible to increase the size of the entire Kl\jjK, and it also has features such as being simple in configuration and easy to implement. .

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a conventional resin-encapsulated semiconductor device, FIGS. 2 and 3 are vertical and enlarged cross-sectional views of the same, and FIG. 4 is a perspective view of a conventional resin-encapsulated semiconductor device. FIG. 5 and FIG. 6 are longitudinal cross-sectional views and enlarged cross-sectional views of the same, and FIG. 7 is an enlarged view of essential parts of the same. C11)...Metal substrate, (12)...Diode element, (13)...Terminal, [14)...
...Resin case, (151...Silicon?-7
', (161...Thermosetting epoxy resin, (17)
...Resin lid. Agent Shin Kuzuno - (1 other person) Figure 1 [Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A semiconductor element and a terminal to be extracted from the semiconductor element are provided on a metal substrate, and a resin case and 7 parts are fitted so as to enclose the semiconductor element on the substrate, and the inside of the case is sealed with resin. In the configuration, a resin case is used that has an opening in a portion corresponding to the side of the element O, the resin case is held in pressure contact with an end far from the element on the substrate, and the opening is closed. 1. A resin-sealed semiconductor device characterized in that the semiconductor device is resin-sealed in a temporarily closed state, and the sealing resin is used to seal and protect the element, and a substrate and a case are bonded together.