JPS5848638B2 - Lead frame partial plating equipment for semiconductor devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a partial plating apparatus for lead frames for semiconductor devices.

In the plating method (hereinafter referred to as the "jet method") in which the plating solution is sprayed from a nozzle to perform partial plating, conventionally a mask made of rubber or silicone rubber is fixed to a holding plate and the pretreatment is carried out using a mask made of rubber or silicone rubber. Completed semiconductor lead frames (hereinafter referred to as ``frames'') were lined up by hand, subjected to partial plating using a jet method, and then the frames were removed for post-processing.

Therefore, it was necessary to manually handle the frame before and after partial plating.

FIG. 1 is a plan view of an example of a lead frame for a semiconductor device.

This example is a lead frame for a semiconductor integrated circuit.

As the material for the frame, iron alloys such as Kohar and 4-27 Roy are used.

Partial plating such as partial gold plating or partial silver plating is performed in a portion 2 of the frame 1 indicated by a broken line.

3 is a semiconductor chip mounting part. Figure 2 shows frame 1
FIG. 3 is a plan view of a mask used for zero-part plating.

As the material of the mask 4, rubber such as silicone rubber is used.

The mask 4 has an opening 5, and partial plating is performed by allowing the plating liquid to pass through the opening 5.

FIG. 3 is a plan view showing the mask attached to the holding plate.

The holding plate 6 is made of resin such as glass epoxy or phenol.

FIG. 4 is a cross-sectional view showing a state in which the holding plate, mask, frame, and presser cover are stacked one on top of the other.

The holding plate 6 has a hole 7 corresponding to the opening 5 of the mask 4.

Frame 1 is placed on mask 4.

In order to prevent the plating solution from leaking out, press it with a presser cover 9 covered with rubber 8.

FIG. 5 is a sectional view of the nozzle part and the vicinity of the solenoid of the partial plating apparatus.

A plating solution is sprayed from the plating solution spray nozzle 10 in the direction of the arrow, and a voltage is applied between the nozzle 10 and the frame 1 to deposit partial plating on the frame 1 corresponding to the opening 5 of the mask 4.

As is well known, partial plating for gold, silver, etc. frames follows the process shown in the process diagram in Figure 6, pre-treatment and post-treatment use separate jigs, and only partial plating is performed. This is usually done using the method described above, which has the disadvantage of being complicated.

This invention was made in view of the above points, and includes two holding plates, a frame holding plate and a mask holding plate,
The mask holding plate is fixed to the stand of the partial plating equipment, and the frame is fixed to the frame holding plate, and pre-treatment, partial plating, and post-processing can be performed without removing the frame from the frame holding plate. The object of the present invention is to provide a partial plating apparatus for lead frames for semiconductor devices that eliminates the need for manual handling of frames and simplifies work.

FIG. 7 is a plan view of a frame holding plate of a partial plating apparatus according to an embodiment of the present invention.

This frame holding plate 11 has only an outer frame, and is provided with pins 12 for fixing the frame and holes 13 for positioning.

FIG. 8 is a diagram showing a state in which a mask is placed on a mask holding plate, and FIG. 8A is a plan view and FIG. 8B is a sectional view.

This mask holding plate 14 is provided with pins 15 for positioning the frame holding plate 11.

FIG. 9 is a plan view showing a state in which the elongated frame 1a is attached to the frame holding plate 11.

The long frame 1a is a frame in which the length of the frame 1 shown in FIG. 1 is made as long as possible, and the number of semiconductor elements that can be attached to one frame is increased.

The long frame 1a is fixed to the frame holding plate 11 with pins 12.

FIG. 10 is a sectional view showing the relationship between the frame holding plate 11 and the mask holding plate 14. FIG.

The frame holding plate 11 on which the frame 1a is placed is positioned on the mask holding plate 14 using positioning pins 15 and pin holes 13, and is pressed down with a presser cover 9 to which rubber 8 is attached.

The plating method is the same as that shown in FIG.

According to the partial plating apparatus according to the present invention, by separating the frame holding plate 11 and the mask holding plate 14, once the frame is attached to the frame holding plate 11, pretreatment can be performed without removing the frame in the middle of the process. , partial plating, and post-processing are now possible, not only eliminating manual labor, but also
Full automation of partial plating is also possible.

Further, since the frame holding plate 11 is made of only the outer frame, there is no risk of contaminating the liquid even if it is used in a continuous process of pre-treatment, partial plating, and post-treatment.

In the above embodiment, the frame holding plate 11 was positioned on the mask holding plate 14 using the positioning pins on the mask holding plate, but another mechanism may be used.

As detailed above, in the lead frame partial plating apparatus for semiconductor devices according to the present invention, since the frame holding plate and the mask holding plate are provided, the mask holding plate is assembled with the frame holding plate only in the plating process. It is now possible to perform continuous work consisting of the partial plating pre-processing process, plating process and post-processing process while the frame is attached to the frame holding plate, which allows (a) to eliminate manual work, and (b) to enable full automation. , C. The time from pre-treatment to plating is shortened, and the effects of oxidation etc. are reduced.

[Brief explanation of drawings]

FIG. 1 is a plan view of an example of a lead frame for a semiconductor device.
Figure 2 is a plan view of the mask used for partial plating, Figure 3
The figure is a plan view showing the mask attached to the holding plate, Figure 4 is a cross-sectional view showing the holding plate, mask, frame, and presser cover stacked one after another, and Figure 5 is the spray nozzle of the partial plating device and its 6 is a process diagram of partial plating, FIG. 7 is a plan view of a frame holding plate of a partial plating apparatus according to an embodiment of the present invention, and FIGS. FIG. 9 is a plan view showing the long frame attached to the frame holding plate, and FIG. 10 shows the relationship between the frame holding plate and the mask holding plate. FIG. In the figure, 1.1a is a frame, 4 is a mask, 5 is an opening of the mask 4, 6 is a holding plate, 7 is a hole, 10 is an injection nozzle, 11 is a frame holding plate, and 14 is a mask holding plate. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A lead frame holding plate that holds a lead frame for a semiconductor device through a pre-plating process, a plating process, and a post-plating process, and a part corresponding to the part of the lead frame to be plated when positioned on the lead frame. a mask holding plate that holds a mask having an opening in the mask, is assembled with the lead frame holding plate only in the plating process, positions the lead frame and the mask, and has a hole in a portion corresponding to the opening of the mask; and a lead frame partial plating apparatus 6 for a semiconductor device, comprising an injection nozzle for injecting a plating solution onto the lead frame through the hole of the mask holding plate and the opening of the mask in the plating process.