JP3287327B2 - Manufacturing method of semiconductor resin sealed package - Google Patents

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.
The present invention relates to a method for manufacturing a body resin sealed package .

[0002]

2. Description of the Related Art A backside heat dissipation type semiconductor to which the present invention is directed.
The manufacturing method of the resin-sealed package is different from a general semiconductor resin-sealed package in that a part of the mount island is exposed on the back side of the 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).

[0010] In a general heat dissipation type semiconductor resin sealed package (not shown) which is not the backside heat dissipation type, that is, the 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. Package manufacturing
The aim is to provide a method .

[0014]

In order to solve the above-mentioned problems, a method of manufacturing a semiconductor-resin-sealed package according to the present invention is described in which a semiconductor element is mounted on a backside heat sink disposed on a mounting substrate side. A method of manufacturing a semiconductor-resin-sealed package in which a lead terminal portion is disposed on a side of the back 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. When forming a bent portion toward the inside of the resin at an end portion of the backside heat sink, after forming a concave portion on the side facing the mounting substrate at a portion serving as a bending base point of the bent portion, bending is performed. " (Claim 1).

(Function) The backside heat dissipation type semiconductor resin sealed package according to the present invention is provided .
According to the manufacturing method, since the bent portion and the concave portion of the backside heat sink are locked to the mold resin, even when a stress for separating the backside heatsink is applied, it is ensured that the backside heatsink and the semiconductor element are separated from the mold resin. Can be prevented. 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]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a semiconductor device manufactured according to the present invention will be described.
A method for manufacturing the conductive resin sealed package will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a backside heat dissipation type semiconductor resin sealing package 10 manufactured according to the present invention;
FIG. 2 is a view taken in the direction of the arrow A in FIG. 1, and FIG.
As can be seen from FIG. 1, the backside heat dissipation type semiconductor resin encapsulation package 10 manufactured by the present invention has a semiconductor element 12 on a backside heat sink 11 arranged on a mounting substrate 17 (FIG. 3) side such as a resin substrate. It is placed. 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 terminals 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 manufactured according to the present invention has the bent portion 1 toward the inside of the mold resin 14 at the end of the backside heat sink 11.
5 and the concave portion 16 is provided on the surface of the bent portion 15 facing the mounting substrate 17 at the bending base point, so that the locking force of the rear 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, the semiconductor device according to the present invention is
According to the manufacturing method of the body resin sealing package, since the bent portion and the concave portion of the backside heat sink are locked to the mold resin, the backside heatsink and the semiconductor element can be used even when a stress acts to separate the backside heatsink from the mold resin. It is possible to reliably prevent peeling from the mold resin, thereby preventing deterioration of characteristics of the semiconductor element and improving stability and reliability.
A possible semiconductor resin-sealed package can be manufactured . And, of the semiconductor resin sealed package according to the present invention,
In the manufacturing method, since the concave portion is provided at the base point of the bent portion, the thickness of the base point is reduced, and it is possible to provide a method of manufacturing a semiconductor resin encapsulated package that is easy to bend and has high productivity.

[Brief description of the drawings]

FIG. 1 is a backside heat dissipation type semiconductor tree manufactured by the present invention .
It is a figure which shows a fat sealing package .

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

FIG. 3 is a semiconductor resin sealing package of a backside heat dissipation type according to the present invention.
It is a figure explaining an operation of a manufacturing method of a cage .

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 (1)

(57) [Claims] 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 the method for manufacturing a semiconductor resin-encapsulated package in which 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 this case, a method of manufacturing a semiconductor resin-sealed package is characterized in that a concave portion is provided at a portion serving as a bending base point of the bent portion on the side facing the mounting substrate, and then the bent portion is bent.