JPH038107B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to improvements in the assembly method of semiconductor devices such as power triacs and thyristors, particularly devices such as modular products in which a large number of electrodes are taken out to the outside. It is.

[Conventional technology]

Hereinafter, a conventional method of assembling a three-terminal thyristor will be explained with reference to FIGS. 4 to 7, taking a three-terminal thyristor as an example.
First, as shown in a plan view in FIG. 4, the ceramic plate 2 is placed on the center of the cooling plate 1 via a printed solder paste (not shown). Ceramic board 2
Paste solder 3 is printed on the upper surface in a desired pattern. Of course, this cooling plate 1 is positioned and fixed to a plate jig 4 of an automatic machine, and the mounting of the ceramic plate 2 and the subsequent supply of each component are performed by this automatic machine. Now, as shown in the plan view in Figure 5, the Y
Glyph basic element 5 to ceramic plate 2
Do not place it on top of the paste solder 3 above. FIG. 6a is an enlarged plan view of this Y-shaped basic element 5, and FIG. 6b is a front view thereof. In the figure,
6 is a first main electrode plate, 7 is a brazing material, 8 is a thyristor chip, 9 is a second main electrode plate, and 10 is a control electrode plate. After that, as shown in the front cross-sectional view in FIG.
are respectively mounted on a corresponding portion of the paste-like solder 3 on the ceramic plate 2, and while being held in some way, the parts are placed in a reflow oven to melt the solder, thereby fixing each part. After that, the case 12 is fixed, and the epoxy resin 13 is injected and cured to complete the assembly.

[Problem that the invention seeks to solve]

The conventional assembly method described above has the problem that it is extremely difficult to fix these parts in the desired position and in the desired posture due to the large number of parts and their shapes. For this reason, it is necessary to hold the components until they are fixed by soldering, and for this reason, conventional semiconductor device assembly requires skill.

[Means for solving problems]

The method for assembling a semiconductor device according to the present invention is to place a plurality of external electrode plates on solder and melt the solder in a reflow oven, thereby positioning each of the external electrode plates at a desired position and in a desired posture. In a method for assembling a semiconductor device in which the semiconductor device is assembled after soldering and sealing, each of the external electrode plates is connected with an assembly jig made of a resin molded product having a heat deformation temperature higher than the melting point of the solder. By forming a structure that can be stably placed on the solder, each of the externally-extracting electrode plates is held at the required position and posture until the externally-extracting electrode plate is fixed by soldering, and The assembly jig is characterized in that the external electrode plates are sealed while being connected.

[Effect]

In this invention, the assembly jig is made of a resin molded product that has a higher heat distortion temperature than solder.
Each external electrode plate is connected to create a structure that can be stably placed on the solder, and in order to hold this in the desired position and posture, the reflow oven is heated while each external electrode plate is held. The assembly jig does not undergo thermal deformation even at the solder melting temperature even when soldered at Therefore, even if the external electrode plates are sealed while being connected using an assembly jig, the electrical characteristics of the semiconductor device will not be affected.

〔Example〕

FIG. 1a is a plan view of only the vicinity of the assembly jig used in one embodiment of the present invention, and FIG. 1b is a front view thereof.
This embodiment shows a case where the present invention is applied to the same three-terminal thyristor as the conventional example described above, and the same reference numerals as in the conventional example indicate equivalent parts, and the description thereof will be avoided from duplication. The assembly process is almost the same as the conventional example. 1st
In the figure, 14 is an external electrode plate holding jig plate as an assembly jig made of a heat-resistant thermoplastic insulating polyphenylene sulfide (PPS) resin molded resin whose heat distortion temperature is higher than the melting point of solder. can be,
As a result, the external electrode plates 11a, 11b, and 11c are maintained in their normal positions, and as shown in the front cross-sectional view in FIG. 11
a, 11b and 11c are mounted on a corresponding portion of the paste solder 3 on the ceramic plate 2 in the same manner as in the conventional case. The following steps are conventional.

Therefore, in order to connect the externally drawn electrode plates 11a, 11b, and 11c by the holding jig plate 14 to create a structure that can be stably placed on the solder, each electrode plate 1
Even if 1a, 11b, and 11c are soldered in a reflow oven while being connected and held, the holding jig plate 14 will not be thermally deformed even at the melting temperature of the solder.
Each electrode plate 11a, 11b, 11c can be stably held until it is fixed,
Each of the electrode plates 11a, 11b, 11c can be correctly fixed at a desired position and in a desired posture, and does not require the skill required in the past.

In addition, since the holding jig plate 14 has insulating properties,
Each electrode plate 11a, 11b, 11 with the holding jig plate 14
Even if they are sealed while connected, the electrical characteristics of the semiconductor device will not be affected in any way.

FIG. 3a is a plan view of only the periphery of the assembly jig used in another embodiment of the present invention, and FIG. 3b is a plan view of its B-
This is a cross-sectional view taken along line B. The external electrode plate holding jig plate 15 used here is the same as the holding jig plate 1 shown in FIG.
4 and case 12 are integrated to facilitate positioning and further facilitate assembly.

Above is the external extraction electrode plate holding jig plate 14, 15
Since both have a heat deformation temperature higher than the melting point of solder, they do not deform even in a reflow oven and perform their holding function.

In the above explanation, the assembly of a three-terminal thyristor was taken as an example, but it is also applicable to triax and module products.

〔Effect of the invention〕

As described above, according to the present invention, a plurality of external electrode plates can be connected and stably placed on the solder using an assembly jig made of a resin molded product having a higher thermal deformation temperature than the solder. In order to hold this in the desired position and posture, the assembly jig will not be thermally deformed even at the solder melting temperature, even if it is soldered in a reflow oven while each external electrode plate is held. It is possible to stably hold each externally-extracting electrode plate until it is fixed, and does not require the same skill as in the past, significantly streamlining the assembly work. This makes it possible to reduce product costs.

In addition, since the assembly jig has insulating properties, even if the external electrode plates are connected and sealed using the assembly jig, the electrical characteristics of the semiconductor device are not affected in any way.

[Brief explanation of the drawing]

Fig. 1a is a plan view of only the vicinity of the assembly jig used in one embodiment of the present invention, Fig. 1b is a front view thereof, Fig. 2 is a front sectional view showing the product assembly situation in this embodiment, and Fig. 3 Figure a is a plan view of only the periphery of the assembly jig used in another embodiment of the present invention, and Figure 3 b is a plan view of the periphery of the assembly jig used in another embodiment of the present invention.
The sectional view taken along line B-B in Figure a, and Figures 4 to 7 are for explaining the conventional example. Figure 4 is a plan view showing the stage in which the ceramic plate is mounted on the jig, and Figure The figure is a plan view showing a stage in which a Y-shaped basic element is placed on the ceramic board, FIG. 6 a is a plan view of the Y-shaped basic element, FIG. 6 b is a front view thereof, and FIG. 7 is a conventional method. FIG. 3 is a front sectional view showing the product assembly situation. In the figure, 3 is a brazing material (solder), 11a, 1
1b, 11c are parts (externally taken out electrode plate), 14,
15 is an assembly jig (external electrode plate holding plate). Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A plurality of external electrode plates are placed on the solder,
In a method for assembling a semiconductor device, in which each of the external electrode plates is soldered at a desired position and in a desired posture by melting the solder in a reflow oven, and then sealed to assemble the semiconductor device, the melting point of the solder is lower than the melting point of the solder. By connecting each of the externally-extracting electrode plates with an assembly jig made of a resin molded product having a high heat deformation temperature, and creating a structure that can be stably placed on the solder, each of the externally-extracting electrode plates can be assembled. The semiconductor device is characterized in that each of the external electrode plates is held at the required position and in the required posture until the electrode plates are fixed by soldering, and the assembly jig is used to seal the external electrode plates while being connected to each other. Assembly method.