JP2000260911A - Semiconductor resin sealed package and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rear surface heat dissipation semiconductor resin sealed package, and a manufacturing method thereof, in which the mold resin is prevented surely from being stripped off from a rear surface heat sink or a semiconductor element. SOLUTION: A semiconductor element 12 is mounted on a rear surface heat sink 11 disposed on the mounting board 17 and a lead terminal 13 is disposed on the side of the rear surface heat sink 11. The rear surface heat sink 11, the semiconductor element 12 and the lead terminal 13 are coated with a mold resin 14 and the rear surface heat sink 11 is exposed. A bend 15 directing toward the inside of the mold resin 14 is provided at the end of the rear surface heat sink 11 and a recess 16 is made at the base point of the bend 15 on the side opposite to the mounting board 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backside heat dissipation type semiconductor resin sealed package and a method of manufacturing the same.

[0002]

2. Description of the Related Art A backside heat dissipation type semiconductor resin-sealed package and a method of manufacturing the same according to the present invention are characterized in that a part of a mount island is exposed on the backside of the package.
This is different from a general semiconductor resin sealing package. Such a backside heat dissipation type semiconductor resin-sealed package is often used when mounting a semiconductor element having a large amount of heat, such as a power amplifier, and not only a lead terminal portion but also a backside heat sink is soldered to a mounting substrate.

Since a large amount of heat generated in the semiconductor element is radiated to the mounting substrate via the backside heat sink, an excessive rise in temperature of the semiconductor element can be prevented, and the semiconductor element has high stability and sufficient reliability. Can be secured.

Conventionally, in a backside heat dissipation type semiconductor resin sealing package 50 as shown in FIG. 4, a semiconductor element 52 is mounted on a backside heat sink 51. Also, on both sides of the backside heat sink 51, lead terminal portions 53 are arranged as shown in FIG.

[0005] As shown in FIG. 4, the backside heat sink 51, the semiconductor element 52, and the lead terminal 53 are covered with a mold resin 54, and the backside heat sink 51 is exposed. The semiconductor element 52 and the lead terminal portion 53 are electrically connected inside the molding resin 54 by a bonding wire (not shown).

[0006] As shown in FIG. 6, this backside heat dissipation type semiconductor resin sealing package 50 is mounted on a mounting substrate 5 such as a resin substrate.
5, first, the solder pads 56 for the lead terminals and the solder pads 5 for the heat sink are mounted on the mounting board 55.
7 is provided. Next, solder paste is printed on each of the solder pads 56 and 57 of the mounting board 55 by a solder printing machine (not shown).

[0007] Next, a mounting device (not shown) puts a semiconductor resin sealing package 50 on the printed solder paste.
Is placed, and the solder paste is melted by an infrared reflow device (not shown) or the like. Thereby, the back surface heat sink 51 and the lead terminal portion 53 of the semiconductor resin sealing package 50 are soldered to predetermined positions on the mounting board 55.

[0008]

However, in the conventional backside heat dissipation type semiconductor resin encapsulation package 50, the backside heat sink 51 and the semiconductor element 52 are separated from the molding resin 54 due to the following reasons. There was a problem.

That is, the molding resin material has a moisture absorbing property, and is stored in a storage environment between the time when the molding resin sealing of the semiconductor resin sealing package 50 is performed and the time when the molding resin material is mounted on the mounting substrate 55. Depending, however, considerable moisture is absorbed into the package. The moisture absorbed by the mounting board 55
During mounting on the package, it is concentrated at the interface between the mold resin 54 and the backside heat sink 51 and the semiconductor element 52, and expands due to vaporization. Direction of peeling (backside heat sink 51
Stress acts in the direction in which it comes down).

In a general heat dissipation type semiconductor resin sealing package (not shown) which is not a backside heat dissipation type, that is, a backside heatsink is not exposed, the heatsink is completely surrounded by the mold resin. Even if the above-mentioned stress acts, the heat sink and the semiconductor element are not easily peeled off. However, in the backside heat dissipation type semiconductor resin sealing package 50, since the lower surface of the backside heat sink 51 is exposed, the above-mentioned stress cannot be supported. The peeling portion 58 is generated at the same time.

When such a stripped portion 58 is generated, moisture is accumulated in the stripped portion 58 and causes the characteristics of the semiconductor element 52 to deteriorate. Further, when the peeling is remarkable, the bonding wire that internally connects the semiconductor element 52 and the lead terminal portion 53 may be cut off when heated in the reflow step.

In order to solve such a problem, as shown in FIG. 7, a tapered portion 59 formed by etching is provided at an end of the backside heat sink 51, and the tapered portion 59 is peeled off by being locked to the mold resin 54. There was a technique that made it difficult, but it was not possible to completely prevent minute peeling.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problem, and has a backside heat sink and a backside heat dissipation type semiconductor resin encapsulation capable of reliably preventing separation of a semiconductor element from a mold resin. An object of the present invention is to provide a package and a manufacturing method thereof.

[0014]

In order to solve the above-mentioned problems, a semiconductor-resin-sealed package according to the present invention comprises a semiconductor device mounted on a backside heat sink disposed on a mounting substrate side, In a semiconductor resin sealing package in which a lead terminal portion is arranged on a side of a heat sink, the back heat sink, the semiconductor element and the lead terminal portion are covered with a resin, and the back heat sink is exposed, an end of the back heat sink is provided. A bent portion directed toward the inside of the resin, and a concave portion provided on a side of the bent base point of the bent portion facing the mounting substrate (claim 1). Further, the method of manufacturing a semiconductor resin-sealed package according to the present invention includes the steps of `` a semiconductor element is mounted on a backside heat sink disposed on a mounting substrate side, and a lead terminal portion is disposed on a side of the backside heat sink, In a method of manufacturing a semiconductor resin sealed package in which a backside heat sink, the semiconductor element, and the lead terminal portion are covered with a resin, and the backside heat sink is exposed, a bent portion toward the inside of the resin is formed at an end of the backside heat sink. In forming (2), after forming a concave portion on the surface facing the mounting substrate at a portion serving as a bending base point of the bent portion, bending is performed (claim 2).

(Function) According to the backside heat-dissipating resin-sealed package and the method of manufacturing the same according to the present invention, since the bent portion and the concave portion of the backside heat sink are locked to the mold resin, the stress for peeling off the backside heat sink is reduced. Even when it acts, the backside heat sink and the semiconductor element can be reliably prevented from peeling from the mold resin. In addition, by providing the concave portion, the thickness of the base point of the bent portion is reduced, so that the bending process is facilitated.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a semiconductor resin-sealed package and a method of manufacturing the same according to the present invention will be described.
This will be described in detail with reference to the drawings. FIG. 1 is a view showing a backside heat dissipation type semiconductor resin sealed package 10 according to the present invention, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG. 3 is an operation of a semiconductor resin sealed package according to the present invention and a method of manufacturing the same. FIG. As can be seen from FIG. 1, the backside heat dissipation type semiconductor resin sealing package 10 according to the present invention includes a backside heat sink 11 disposed on a mounting substrate 17 (FIG. 3) side such as a resin substrate.
The semiconductor element 12 is mounted thereon. As the semiconductor element 12, a semiconductor element having a large heat value such as a power amplifier is used.

On both sides of the backside heat sink 11,
As shown in FIG. 2, the lead terminal portion 13 is provided. Then, the backside heat sink 11, the semiconductor element 12, and the lead terminal portion 13 are covered with the mold resin 14, and the backside heat sink 11 is exposed.

The semiconductor resin sealed package 10
As shown in FIG. 1, a bent portion 15 directed toward the inside of the mold resin 14 is provided at an appropriate angle at an end of the backside heat sink 11. Further, the bent portion 15
A concave portion 16 is provided continuously or intermittently over the entire length on the side facing the mounting substrate 17 at the bending base point.

When the semiconductor resin-sealed package 10 is mounted on a mounting board 17 such as a resin board as shown in FIG. 3, a solder pad 18 for a lead terminal portion and a heat sink A solder pad 19 is provided. Next, a solder paste is printed on each of the solder pads 18 and 19 of the mounting board 17 by a solder printing machine (not shown).

Next, the heat sink 11 and the lead terminal portion 13 of the semiconductor resin sealing package 10 are placed on the solder paste printed by a mounting machine (not shown) with the infrared reflow device (FIG. (Not shown) to melt the solder paste. Thereby, the back surface heat sink 11 and the lead terminal portion 1 of the semiconductor resin sealing package 10 are formed.
3 is mounted on a predetermined position of the mounting board 17 by soldering.

As described above, the semiconductor resin sealing package 10 according to the present invention is provided with the bent portion 15 toward the inside of the mold resin 14 at the end of the backside heat sink 11.
Furthermore, since the concave portion 16 is provided on the surface of the bent portion 15 facing the mounting substrate 17 at the bending base point, the locking force of the back heat sink 11 to the mold resin 14 is increased.

Therefore, even if the moisture accumulated inside due to the hygroscopicity of the mold resin 14 is heated and expanded at the time of mounting, and the stress due to the expansion acts in the direction of peeling the backside heat sink 11 from the mold resin 14,
Separation of the backside heat sink 11 and the semiconductor element 12 from the mold resin 14 can be reliably prevented.

Therefore, unlike the conventional case, no peeling portion is generated between the backside heat sink 11 and the semiconductor element 12 and the mold resin 14, and the characteristics of the semiconductor element 12 are degraded by the moisture accumulated in the peeling portion. Can be prevented, and stability and reliability can be improved. Further, by providing the concave portion 16 at the base point of the bent portion 15, the thickness of the base point is reduced, and the bending process is facilitated. As a result, the stress applied to the heat sink flat portion during processing can be reduced, and the flatness of the heat sink flat portion can be ensured.

[0024]

As described above, according to the semiconductor-resin-sealed package and the method of manufacturing the same according to the present invention, the bent portion and the concave portion of the backside heat sink are locked by the mold resin. Even when stress is applied to separate the back surface heat sink and the semiconductor element from the mold resin, it is possible to reliably prevent the back surface heat sink and the semiconductor element from being separated from the mold resin, thereby preventing the characteristic deterioration of the semiconductor element and improving the stability and reliability. It is possible to provide a semiconductor resin sealed package that can be improved and a method for manufacturing the same. Also, since the concave portion is provided at the base of the bent portion, the thickness of the base is reduced,
It is possible to provide a highly productive semiconductor resin sealed package that can be easily bent and a method of manufacturing the same.

[Brief description of the drawings]

FIG. 1 is a diagram showing a backside heat dissipation type semiconductor resin sealing package according to the present invention.

FIG. 2 is a view taken in the direction of arrow A in FIG. 1;

FIG. 3 is a view for explaining the operation of the semiconductor resin-sealed package of the backside heat dissipation type and the method of manufacturing the same according to the present invention.

FIG. 4 is a view showing a backside heat dissipation type semiconductor resin sealing package according to a conventional example.

FIG. 5 is a view taken in the direction of arrow B in FIG. 4;

FIG. 6 is a diagram illustrating the operation of a backside heat dissipation type semiconductor resin sealing package according to a conventional example.

FIG. 7 is a view showing another example of a backside heat dissipation type semiconductor resin sealing package according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Semiconductor resin sealing package 11 Backside heat sink 12 Semiconductor element 13 Lead terminal part 14 Mold resin 15 Bend part 16 Concave part 17 Mounting substrate 18 Lead terminal part solder pad 19 Heat sink solder pad

Claims (2)

[Claims] 1. A semiconductor element is mounted on a backside heat sink disposed on a mounting substrate side, and a lead terminal portion is disposed on a side of the backside heat sink, wherein the backside heat sink, the semiconductor element, and the lead terminal portion are arranged. In the semiconductor resin sealing package, which is covered with resin and the backside heat sink is exposed, a bent portion toward the inside of the resin is provided at an end of the backside heat sink, and the bent portion has a bent base point with the mounting substrate. A semiconductor-resin-sealed package, wherein a concave portion is provided on the opposing surface side. 2. A semiconductor element is mounted on a backside heat sink disposed on a mounting substrate side, and a lead terminal portion is disposed on a side of the backside heatsink, and the backside heat sink, the semiconductor element, and the lead terminal portion are arranged. In the method of manufacturing a semiconductor resin sealed package covered with a resin and exposing the backside heat sink, when forming a bent portion toward the inside of the resin at an end of the backside heat sink, a bending base point of the bent portion A method of manufacturing a semiconductor-resin-sealed package, comprising: forming a concave portion on a surface facing the mounting substrate at a portion to be formed;