JP2997182B2 - Resin encapsulated semiconductor device for surface mounting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealed semiconductor device for surface mounting.

[0002]

2. Description of the Related Art As shown in a plan view of FIG. 3A, an elevation view of FIG. 3B, and a right side view of FIG. The resin molded part 15 has one end (hereinafter referred to as “upper resin molded part”) 12 and the other end (hereinafter referred to as “lower resin molded part”) 11 having a smaller resin molded thickness sandwiches the internal lead wire. In some cases, the external lead wire 14 is arranged so that one surface is located on the same surface as the bottom surface 17 from the lower resin molded portion 11 side. Then, the upper resin molding section 12 and the lower resin molding section 1
1 (hereinafter referred to as "parting line")
3 has the same joint cross-sectional size.
That is, the sizes of the cross sections of the upper resin molded part 12 and the lower resin molded part 11 passing through the parting line 13 are the same.

As shown in FIG. 4, only the main part of the resin-sealed portion of the surface-mounted resin-sealed semiconductor device is formed as follows.
The upper resin molded part molding die 18 (FIG. 4 (a)) and the lower resin molded part molding die 19 (FIG. 4 (b)) are divided into two parts. The resin molding die 20 having the same size is used. In addition,
4C is a cross-sectional view taken along line AA of FIG. 4A, and FIG. 4D is a cross-sectional view taken along line BB of FIG. 4B.

[0004]

Generally, a resin-sealed mold semiconductor device is finished by deburring the resin after resin-sealing molding. In this resin deburring step, it was observed that cracks, chips or cracks occurred in the lower resin molded portion 11 having the smaller thickness of the resin molded portion.

When the cause was investigated, the upper resin molding portion 12 and the lower resin molding portion 11 were resin-sealed in a state where they were displaced from each other at the joining surface during the resin molding process, and a plan view of FIG.
As shown in the elevation view of FIG. 3B and the right side view of FIG. 3C, a portion 21 where the resin has protruded is formed in the lower resin molding portion 11 having the smaller thickness of the resin molding portion. It was found that the resin medium of the blast used in the deburring step hits the resin part having a smaller thickness, causing cracks, chips or cracks.

According to the present invention, even if the lower joining surface of the thinner part is displaced from the upper joining part of the thicker resin molding part by the molding conditions at that time after the resin molding, An object of the present invention is to provide a surface-mounting resin-sealed semiconductor device in which cracks, chips or cracks do not occur in a lower part of a thinner resin molded part in a deburring step after the resin molding.

[0007]

According to the present invention, in order to achieve the above object, the lower part (one end) and the upper part (the other end) of the resin-encapsulation molding are integrated with a parting line with a lead wire interposed therebetween. A resin-encapsulated semiconductor device for surface mounting formed by molding, wherein a cross-sectional area on a parting line surface of a resin molding lower part (one end) having a small resin molding thickness is reduced by a resin molding upper part (a large resin molding thickness). The semiconductor device is smaller than the cross-sectional area on the parting line surface at the other end, and the cross-sectional area of the lower part (one end) of the resin molding is included in the cross-sectional area of the upper part (other end) of the resin molding. Things.

[0008]

The cross section of the resin molded portion along the parting line at one end where the resin thickness is small is smaller than the cross section along the parting line at the other end where the resin thickness is thick, and Since the cross-sectional periphery of the thinner end does not protrude from the cross-sectional periphery of the thicker other end, cracks, chips, or cracks occur even if the blasted resin media hits in the resin deburring process. Nothing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the resin-sealed semiconductor device for surface mounting according to the present invention will be described below in detail with reference to FIG.

In FIG. 1, (a) is a plan view of a resin semiconductor device for surface mounting, (b) is an elevation view, and (c) is a right side view.

In this embodiment, a resin sealing upper part 2 and a lower part 1 are integrally formed, and a parting line 3 is formed.
The resin molding thickness of the resin molding upper part 2 is smaller than the resin molding thickness of the resin molding lower part 1 with respect to the surface along the boundary. Then, a thin strip-shaped lead wire 4 is led out from the resin molded lower part 1 side such that one surface is located on the bottom surface of the lower part 1. The size of the rectangular cross section passing through the parting line 3 of the resin molding lower part 1 is 0.1 μm in the length of one side of the rectangular cross section passing the parting line 3 of the resin molding upper part 2. Or 50 μm
On the surface passing through the parting line 3, that is, in a region surrounded by the cross-sectional periphery passing through the parting line 3 of the resin molding upper part 2. The cross-sectional area of the resin molding lower part 1 is smaller than the cross-sectional area of the resin molding upper part 2, and the cross-sectional area of the resin molding lower part 1 is included in the cross-sectional area of the resin molding upper part 2.

For this reason, the surface-mounted resin-encapsulated semiconductor device does not crack, chip, or crack even if the blasted resin medium in the resin deburring step hits, and as a result, the production yield and the reliability are improved. Can be significantly increased.

By the way, even if there is a temperature difference of ± 5 ° C. at a molding temperature of 170 ° C. at the time of the resin encapsulation molding, such a resin-encapsulated semiconductor device of the present invention has the following resin It can be realized by satisfying the sealing molding conditions.

FIGS. 2A and 2B are diagrams for explaining this resin sealing molding method. FIG. 2A is a plan view of a main part of a molding upper molding die, and FIG. Main part plan view,
(C) is a sectional view taken along line AA in (a),
(D) is a sectional view taken along the line BB in (b). In FIG. 2C, the dimension x is equal to the thickness of the resin molding upper part 2, and in FIG. 2D, the dimension y is equal to the thickness of the resin molding lower part 1 and substantially equal to the thickness of the lead wire 4. be equivalent to.

When designing the resin molding die, the molding temperature of the resin sealing material at the time of resin molding is set, and the expansion coefficient of the resin molding die, the expansion coefficient of the comb material at the upper and lower limits of the temperature, and the resin sealing The resin mold is designed in consideration of the shrinkage of the material.

At this time, the size of the thinner parting line cross section of the resin molding is made smaller than that of the thicker parting line cross section.

In the case of multi-cavity molding, the design and manufacture of the mold are performed in consideration of the expansion coefficient and the like of the pitch of the resin mold and the dimension between rows.

The manufactured resin molding die is set in a resin molding machine, and resin molding is performed according to molding temperature conditions at the time of design.

As a result, the parting line cross section of the resin molded thin resin molding is smaller than the thick parting line cross section by about 0.1 μm to 50 μm, and passes through the parting line 3 of the resin molded lower part 1. The peripheral edge of the cross section is formed without protruding from the peripheral edge of the cross section passing through the parting line 3 of the resin molding upper part 2, and the external lead wire 4 is formed in parallel with the bottom surface of the resin.

In this embodiment, the lower portion of the resin molded portion corresponds to the lower portion of the resin molded portion, and the upper portion of the resin molded portion corresponds to the upper portion of the resin molded portion. Can also be adapted.

[0021]

According to the surface-mounted resin-sealed semiconductor device of the present invention, the cross-section of the lower or upper portion of the resin molded portion having the smaller resin molded thickness in the cross section bisected by the parting line has a larger size. Smaller than the size of the cross section, and the cross-sectional edge of the smaller resin molded part does not protrude from the larger cross-sectional edge, so that even if the resin media of the blast in the resin deburring process hits, This is a surface-mounted resin-sealed semiconductor device free from chipping or cracking, and brings great benefits such as improvement in yield and reliability.

[Brief description of the drawings]

FIG. 1A is a plan view of a resin-encapsulated semiconductor device for surface mounting according to an embodiment of the present invention. FIG. 1B is an elevation view of the same, and FIG.

FIG. 2 is a configuration diagram of a molding die for forming an upper portion used in manufacturing the embodiment shown in FIG. 1;

FIG. 3A is a plan view showing an example of a conventional resin-mounted semiconductor device for surface mounting, FIG. 3B is an elevation view thereof, and FIG. 3C is a right side view thereof.

4 is a configuration diagram of a molding upper molding die used for resin sealing molding of the conventional example shown in FIG.

5 (a) is a plan view showing the protrusion of the resin portion with the smaller thickness of the resin molded portion in the conventional example shown in FIG. 3; (b) is an elevational view; and (c) is a right side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper resin molding part 2 Lower resin molding part 3 Parting line 4 Lead wire

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 23/28 H01L 21/56

Claims (1)

(57) [Claims] 1. One end and the other end of a resin-sealed molded portion are integrally formed by a parting line, and a cross-sectional area on a surface passing through the parting line on one end side where the resin molding thickness is small. Is smaller than the cross-sectional area on a plane passing through the parting line on the other end side where the resin molding thickness is large, wherein the cross-sectional area of the one end is included in the cross-sectional area of the other end. Surface mounted resin-sealed semiconductor device.