JPH0697643A - Solder surface mount equipment - Google Patents

Abstract

PURPOSE:To prevent solder connection failure, by a method wherein a stage or a heater are displaced so as to keep parallelism when pressure is applied in the state that the stage and the heater deviate from parallelism. CONSTITUTION:By arranging an elastic member 5 between an equipment stand 6 and a stage 4, parallelism of the stage 4 and the heater 2 are always maintained by the effect of the elastic member 5, when a heater 2 applies pressure to an outer lead 1a of a semiconductor device 1, so that the heater 2 applies uniform pressure to the outer lead 1a of the semiconductor device 1, and prevents solder connection failure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solder surface mounting technique for a flat type semiconductor device, and more particularly to a technique capable of preventing a solder connection failure between an outer lead and a mounting substrate which occurs in an assembly process, a mounting process and the like. It is a thing.

[0002]

2. Description of the Related Art Conventionally, an apparatus for soldering an outer lead of a flat type semiconductor device and a mounting substrate supports a mounting substrate on which the semiconductor device is temporarily fixed on a stage, and heats a heater to the outer side of the semiconductor device. It is common to pressurize the leads and solder them.

An example of such a conventional solder surface mounting apparatus will be described with reference to FIG.

In FIG. 1, first, the mounting substrate 3 to which the semiconductor device 1 is temporarily fixed is placed on the upper surface of the stage 4 provided on the device mount 6. Next, the heater 2 is lowered to pressurize the outer leads 1a, so that the outer leads 1a of the semiconductor device 1 are soldered to the mounting substrate 3.

Incidentally, as an example of a document describing the mounting technology of a semiconductor device, Applied Technology Publishing Co., Ltd. 1988 is available.
Issued on November 16, 2015, by Murakami, "Mounting Technology for Surface Mount LSI Packages and Improving Its Reliability", Nos. 346 to 347
Page.

[0006]

However, in the technique shown in FIG. 4, the stage 4 and the heater 2 are required to have a high degree of parallelism when soldering the outer leads 1a of the semiconductor device 1. After the replacement of item 2, the parallelism is adjusted each time the device is maintained.

However, the adjustment takes too much time due to the manual work, and the flatness of the stage 4 and the heater 2 is deteriorated due to the adhesion or dirt of the stage 4, the mounting substrate 3 and the heater 2, so that the precision is high. It is difficult to maintain the parallelism, and there is a problem that the outer lead 1a is not pressed and heated as shown in FIG.

An object of the present invention is to provide a solder surface mounting device capable of preventing a solder connection failure between the outer lead of a flat type semiconductor device and a mounting substrate.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, even when the stage or the heater is misaligned and the accuracy of the parallelism between the stage and the heater cannot be maintained, the parallelism of the stage can be prevented by the solder connection failure preventing means provided between the apparatus stand and the stage. The structure is such that it follows the deviation of the gap and maintains the parallelism with the heater.

The same result as described above can be obtained also by providing the solder connection failure prevention means between the heater and the heater base holding the heater.

[0013]

According to the above-mentioned means, since it is possible to constantly pressurize and heat the outer leads extending on the four sides of the semiconductor device evenly, it is possible to prevent defective solder connection.

Further, since it is not necessary to perform the troublesome adjustment of the parallelism at the time of replacing the heater or maintaining the apparatus, the workability can be improved.

[0015]

Embodiment 1 FIG. 1 is a front view showing a solder surface mounting apparatus which is an embodiment of the present invention.

As the structure for supporting the semiconductor device 1, a device base 6 made of metal to serve as a base of the device, and a stage 4 made of metal similar to the device base 6 to which the mounting substrate 3 is attached, The device base 6 and the stage 4
An elastic body 5 (solder connection failure prevention means) formed of silicone rubber or the like is interposed between the two by means of an adhesive or the like.

On the other hand, as a structure on the side where soldering is performed, a heater element 2a which is a heat source is embedded in a heater 2 made of a metal material having a high thermal conductivity, and the heater 2 is provided above the heater 2. An air cylinder 2b for lowering and pressurizing is installed.

The operation of this embodiment will be described below.

When performing soldering, first, the mounting substrate 3 with the semiconductor device 1 temporarily fixed on the upper surface of the stage 4 is mounted.
Attach.

Next, the heater 2 is lowered by the air cylinder 2b to pressurize the outer lead 1a of the semiconductor device 1. When the pressure is applied with the parallelism between the stage 4 and the heater 2 deviated as shown in FIG. 2, the elastic body 5 is deformed and the stage 4 is displaced so as to maintain the parallelism with the heater 2. , The outer leads 1 extending to the four sides of the semiconductor device 1
Since a is uniformly pressed, it is possible to prevent the occurrence of defective solder connection.

Even when foreign matter such as dust adheres to the stage 4 and the heater 2 and the flatness of the stage 4 and the heater 2 is impaired, the heater 2 presses the outer lead 1a of the semiconductor device 1. Since the elastic body 5 is deformed at the time of performing, all the outer leads 1a are uniformly pressed, and similarly to the above, it is possible to prevent the occurrence of defective solder connection.

[0022]

[Embodiment 2] FIG. 3 is a partial sectional view showing a solder surface mounting apparatus according to another embodiment of the present invention.

The present embodiment is characterized in that the elastic body 5, which is means for preventing defective solder connection, is provided on the heater 2 side for soldering.

First, the stage 4 supporting the semiconductor device 1
The side is composed of a device base 6 which is made of metal and serves as a base of the device, and a stage 4 which is made of metal like the device base 6 and to which the mounting substrate 3 is attached.

On the side of the heater 2 for soldering, an elastic body 5 (solder connection failure prevention means) made of silicone rubber or the like is bonded between the heater 2 and the heater base 7 with an adhesive or the like. It is installed.

In the second embodiment, as in the first embodiment, when the heater 2 is lowered to pressurize the outer leads 1a of the semiconductor device 1, the parallelism between the stage 4 and the heater 2 is increased. When pressure is applied in a state of deviation, the elastic body 5 is deformed, the heater 2 is displaced so as to maintain parallelism with the stage 4, and the outer leads 1a extending to the four sides of the semiconductor device 1 are deformed.
Is uniformly applied, it is possible to prevent the occurrence of defective solder connection.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, as means for preventing defective solder connection,
Means other than the elastic body described above may be used.

[0029]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

That is, even if the parallelism between the stage and the heater is deviated, the semiconductor device is soldered to the mounting substrate by providing the solder connection failure prevention means on at least one of the stage side and the heater side. It is possible to prevent defective solder connection.

Further, since it is not necessary to carry out troublesome adjustment of the parallelism at the time of inspecting the apparatus and performing maintenance, it is possible to improve workability.

[Brief description of drawings]

FIG. 1 is a front view showing a solder surface mounting apparatus that is an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a solder surface mounting apparatus that is an embodiment of the present invention.

FIG. 3 is a partial cross-sectional view showing a solder surface mounting device according to a second embodiment of the present invention.

FIG. 4 is a partial cross-sectional view showing a solder surface mounting device having a conventional structure.

[Explanation of symbols]

 1 Semiconductor Device 1a Outer Lead 2 Heater 2a Heater Element 2b Air Cylinder 3 Mounting Board 4 Stage 5 Elastic Body (Solder Connection Failure Prevention Means) 6 Device Stand 7 Heater Stand

Claims (5)

[Claims] 1. An apparatus for soldering an outer lead of a flat type semiconductor device and a mounting substrate by a partial heating method, the parallelism between a stage supporting the semiconductor device and a heater for heating and pressurizing. A solder surface mounting device, characterized in that means for preventing a solder connection failure due to misalignment is provided. 2. The solder surface mounting device according to claim 1, wherein the stage is displaced so as to follow the deviation of the parallelism of the heater and maintain the parallelism with the heater. 3. The solder surface mounting apparatus according to claim 1, wherein the heater is displaced so as to keep the parallelism with the stage by following the deviation of the parallelism of the stage. 4. The solder surface mounting device according to claim 1, wherein the solder connection failure prevention means is an elastic body provided on the stage side. 5. The solder surface mounting device according to claim 1, wherein the solder connection failure prevention means is an elastic body provided on the heater side.