JPS6054784B2 - IC package manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an IC package, and more particularly, the present invention relates to a method for manufacturing an IC package, and more specifically, a method for manufacturing an IC package, and more particularly, a method for manufacturing an IC package, and more particularly, a method for manufacturing an IC package, and more particularly, a method for manufacturing an IC package. The present invention relates to a method of manufacturing an IC package that achieves adhesion.

As a prior art of the manufacturing method of such an IC package, as shown in FIG. In addition to printing and transfer methods, there is a method of pouring adhesive to apply the adhesive to the contact portions 3, 3, 3, 3 of the case 2 and the substrate 1 in order to completely isolate the adhesive from the adhesive.

However, in the case of the prior art that adopts the final pouring method, since the adhesive is plastic-based, the adhesive shown in FIG. As shown in FIG. 2, the outer periphery of the adhesive 4 has a parabolic shape that dips toward the case and the board. Therefore, since such a shape greatly limits the amount of adhesive, (1) it becomes difficult to apply the adhesive to the extent necessary to obtain a sufficient adhesive effect;
2) There is a risk that the so-called sealing effect that isolates the inside of the case from the outside air may not be obtained sufficiently.(3) It may become difficult to securely attach the case to the circuit board, which may cause vibrations that are expected during long-term use. This causes problems such as the case sometimes peeling off from the board. SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a method for manufacturing an IC package that eliminates the above-mentioned problems.

In summary, the present invention is applicable to the first bonding operation when bonding a case and a board using an adhesive whose main component is an epoxy resin with rich thixotropic properties (commonly called dip resin, hereinafter referred to as such). In this case, the case and the board are bonded by leaving a partially unbonded part between the case and the board, and in the case of the second bonding operation, the unbonded part is The case is designed to be bonded to the board so that the problem occurs.

FIG. 3 is a diagram for explaining one step of the manufacturing method according to the embodiment of the present invention. In the same figure, dip resin 21
When the open side of the case 23 is immersed in the dip resin solution into the container 22 filled with water, the case 23 is removed by lifting the part of the case 23 indicated by the arrow.
3 is immersed in the solution with the opening side inclined with respect to the horizontal plane.

The degree of inclination is determined by the solid line 2, which is the liquid level of the dip resin solution.
4 (horizontal line) and a broken line 25 which is the ridgeline on the opening side of the case 23. Therefore, as shown in FIG. 4, the case immersed in the dip resin solution as described above has the dip resin 21 attached to the opening side at the bottom of the figure.

As is clear from FIG. 5, which is a cross-sectional view taken along the section line 1--1, this attachment form has a substantially circular cross section at the open end of the case 23. When the case 23 to which the dip resin is attached in this manner is attached to the substrate 26, as shown in FIG. The shape will be . Therefore, in the case of the present invention, compared to the case of the prior art (FIG. 2), the amount of adhesive increases by the amount of outward expansion, and as a result, the above-mentioned (1) to ( 3) The problem is solved.

Next, on the opening side of the case 23, as shown in FIG. 4, there is a part where the dip resin is not attached, and the case is bonded to the board for the first time with such an unattached part. In the bonding operation, an unbonded part will remain between the case and the board.In this example, the dip resin was applied with some of the unbonded part remaining. Heat and then cure.

Then, the air inside the case expands due to the above heating, but since there is an unbonded part, the air inside the case can go outside through that part, and the gas generated during curing can also go outside. This is highly desirable in order to obtain stable adhesive bonding. After the dip resin is cured, the unbonded parts are coated with the same resin for sealing (second bonding operation), and then heated and cured. As described above, according to the present invention, the dip resin is attached to the periphery of the case opening so that the cross section has a substantially circular shape. Since it has a parabolic shape that expands from Since it can exit to the outside through the unbonded portion of the case and the substrate, a stable mounting state can be obtained, and an IC package with sufficient sealing effect and excellent strength resistance can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an IC package for explaining the prior art, FIG. 2 is a cross-sectional view of a part of the above IC package, and FIG. 3 is for explaining one step of the manufacturing method according to an embodiment of the present invention. FIG. 4 is a diagram showing how the dip resin is adhered to the case in the above process, FIG. 5 is a cross-sectional view of a part of the case in FIG. 4, and FIG. 6 is a diagram showing the relationship between the case and the board according to the above embodiment. It is a cross-sectional view of a part of the IC package showing the adhesion state. 21... Dip resin, 22... Container, 23... Case, 26... Substrate.

Claims (1)

[Claims] 1. In a method for manufacturing an IC package mounted on a substrate, a part of the periphery of the opening of the case is immersed in a dip resin solution, and the dip resin is applied to the part of the periphery of the opening approximately in cross section. an adhesion step in which the case is adhered in a circular shape, and a first adhesion step in which the case is adhered to the substrate after this step is completed, and the dip resin is heated to exhaust the air inside the case from the portion where the dip resin is not attached. and a second bonding step of bonding the unattached portion and the case with a dip resin after the first bonding step is completed.