JPH0964263A - Lead frame plating apparatus and lead frame plating method - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a lead frame plating apparatus and a plating method in which a plating solution does not circulate to the back surface of a die pad of a lead frame when the plating solution is sprayed from a spray nozzle. A lead frame 2 is sandwiched between a mask rubber 3 having a through hole 3a provided in a mask jig 4 having a through hole 4a and a silicone rubber 1a provided in a press block 1. The plating solution in the plating solution tank 10 is guided to the injection nozzle 5 by the supply line 21,
Through hole 4a of mask jig 4 and through hole 3 of mask rubber 3
It is jetted from a to the lead frame 2. In this case, the lead frame 2 is adsorbed by the die pad adsorption holes 12 provided in the silicone rubber 1a and
Adhere to the a side. Therefore, the plating solution does not flow around the back surface of the lead frame 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead frame plating apparatus and a lead frame plating method for plating a lead frame by spraying a plating solution.

[0002]

2. Description of the Related Art Conventionally, a plating apparatus shown in FIG. 5 has been known as a lead frame plating apparatus. As shown in FIG. 5, the plating apparatus includes a mask jig 4 having a through hole 4a and a press block 1 that holds the lead frame 2 between the mask jig 4 and the mask jig 4. The mask rubber 3 is attached to the upper surface of the jig 4.

Of these, the press block 1 is made of heat-resistant vinyl chloride, and a silicon rubber 1a is attached to the lower surface of the press block 1. The mask rubber 3 attached to the mask jig 4 is also provided with a through hole 3a corresponding to the through hole 4a of the mask jig 4. These through holes 4a,
The shape of 3a is the plated portion 3 of the lead frame 2 described later.
It is set in correspondence with 0.

The mask jig 4 is installed at the upper end opening of an outer tank 15 for receiving a plating solution, and in the outer tank 15, an injection tank 6 having an injection nozzle 5 is arranged.

A plating solution tank 10 for storing a plating solution is provided outside the outer tank 15, and the plating solution tank 10 and the injection tank 6 are connected by a supply line 21 to which a pressure pump 9 is attached. Has been done. Outer tank 1
The bottom of 5 and the plating solution tank 10 are connected by a return line 22.

In such a lead frame plating apparatus, first, the lead frame 2 is sandwiched between the mask rubber 3 of the four mask jigs and the silicon rubber 1a on the press block 1 side. Next, the plating solution in the plating solution tank 10 is supplied into the injection tank 6 by the pressure pump 9 through the supply line 21. Further, the plating solution in the spray tank 6 is supplied from the spray nozzle 5 to the through hole 4a of the mask jig 4.
And the lead frame 2 through the through hole 3a of the mask rubber 3.
Is jetted against. In this case, the lead frame 2 is used as a cathode and electricity is applied to the lead frame 2, and thus the lead frame 2 is plated.

The plating solution sprayed onto the lead frame 2 is then accumulated in the outer tank 15 and returned from the bottom of the outer tank 15 through the return line 22 into the plating solution tank 10.

When the lead frame 2 is plated as described above, the lower surface of the lead frame 2 shown in FIG.
A plated portion 30 as shown in is formed. In FIG. 6, the lead frame 2 has a die pad 2a and a lead portion 2b, and the plated portion 30 is formed on the die pad 2a and the lead portion 2b around the die pad 2a.

[0009]

By the way, when the plating solution is sprayed onto the lead frame 2, the lead frame 2 is sandwiched between the mask rubber 3 of the mask jig 4 and the silicon rubber 1a on the press block side. However, as described above, the mask jig 4 and the mask rubber 3 have the plated portion 3
Through holes 4a and 3a are provided corresponding to 0. Therefore, when the lead frame 2 is sandwiched between the mask rubber 3 on the mask jig 4 side and the silicon rubber 1a on the press block 1 side, the die pad 2a portion of the lead frame 2 is not pressed from the mask rubber 3 side. When the plating solution is sprayed onto the lead frame 2 in such a state, among the lead frames 2, especially the die pad 2a
The plating solution wraps around to the back surface (upper surface) side, and the wraparound plating solution forms an additional plated portion 31 on the upper surface of the die pad 2a of the lead frame 2 (see FIG. 7).

In order to prevent such a situation, the mask rubber 3
However, it is not possible to effectively prevent the plating solution from entering the back surface side of the lead frame 2.

The present invention has been made in consideration of the above points, and a lead frame plating apparatus and a lead frame plating method capable of effectively preventing the plating solution from flowing around the back surface of the lead frame. The purpose is to provide.

[0012]

According to the present invention, a lead frame having a die pad is placed, and a mask jig having through holes provided corresponding to the die pad, and the mask jig are provided. A press block for sandwiching the lead frame between them, and a spray nozzle disposed near the through hole of the mask jig and spraying a plating solution to the lead frame through the through hole.
A lead frame plating device characterized in that a die pad suction hole is provided on the surface that comes into contact with the die pad, and a lead frame having a die pad is made to correspond to the through hole on a mask jig having a through hole. Mounting step, sandwiching the lead frame on the mask jig with the press block, sucking the die pad of the lead frame with the die pad suction holes provided in the press block, and mask treatment. And a step of spraying a plating solution through a through hole from a spray nozzle arranged in the vicinity of the through hole of the tool onto the lead frame.

According to the present invention, the die pad of the lead frame is adsorbed by the die pad adsorption hole of the press block, and the die pad is brought into close contact with the press block. Therefore, when the plating solution is sprayed onto the lead frame, The plating solution does not go around to the back surface.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views showing a first embodiment of a lead frame plating apparatus according to the present invention.

In the embodiment shown in FIG. 1, the same parts as those in the prior art shown in FIG. 5 are designated by the same reference numerals and detailed description thereof will be omitted. As shown in FIG. 1, the plating device has a through hole 4a.
The mask jig 4 having the above and the press block 1 for sandwiching the lead frame 2 between the mask jig 4 and the mask jig 4 are provided, and the mask rubber 3 is attached to the upper surface of the mask jig 4. .

The press block 1 is made of heat-resistant vinyl chloride, and a silicon rubber 1a is attached to the lower surface of the press block 1. The mask rubber 3 attached to the mask jig 4 is also provided with through holes 3a corresponding to the through holes 4a of the mask jig 4. The shapes of the through holes 4a and 3a are determined corresponding to the plated portion 30 (see FIG. 7) of the lead frame 2.

The mask jig 4 is installed in the upper end opening of an outer tank 15 for receiving the plating solution, and in the outer tank 15, an injection tank 6 having an injection nozzle 5 is arranged.

A plating solution tank 10 for storing a plating solution is arranged outside the outer tank 15, and the plating solution tank 10 and the injection tank 6 are connected by a supply line 21 to which a pressure feed pump 9 is attached. Has been done. Outer tank 1
The bottom of 5 and the plating solution tank 10 are connected by a return line 22.

Next, the material of each part will be described. Outer tank 1
5, injection tank 6, plating tank 10, supply line 21
The return line 22 is made of heat-resistant PVC or normal PVC, and the injection nozzle 5 is made of SUS and also serves as an anode during plating.

By the way, as shown in FIGS. 1 and 2A and 2B, a die pad suction for adsorbing the die pad 2a of the lead frame 2 is formed on the surface of the silicon rubber 1a provided on the press block 1. A plurality of holes 12 are provided. Here, FIG. 2A is a side view of the press block 1, and FIG. 2B is a bottom view of the press block 1.

As shown in FIGS. 2A and 2B, the die pad suction hole 12 has a vacuum pump 1 through a communicating passage 13 extending through the silicon rubber 1a and the press block 1.
1 has been contacted. Instead of the vacuum pump 11, an ejector, an aspirator or the like may be used.

When the lead frame 2 is placed on the mask rubber 3 on the mask jig 4 side, the die pad 2a of the lead frame 2 is located at a position corresponding to the die pad suction hole 12. Then, by operating the vacuum pump 11, the die pad 2a is sucked by the die pad suction hole 12, and the die pad 2a is attached to the silicone rubber 1a.
It is designed to be in close contact with the side.

Next, the operation of this embodiment having such a configuration will be described. In FIG. 1, the lead frame 2 is placed on the mask rubber 3 of the mask jig 4, the press block 1 descends with respect to the lead frame 2, and the mask rubber 3 of the mask jig 4 and the silicon rubber of the press block 1 are placed. The lead frame 2 is sandwiched between the lead frame 1 and 1a. In this case, the through hole 4a of the mask jig 4 and the mask rubber 3
Through hole 3a is the plated portion 30 of the lead frame 2 (FIG. 6).
The die pad 2a of the lead frame 2 covers the die pad suction hole 12.

Thereafter, the vacuum pump 11 is operated, and the die pad 2a is adsorbed by the die pad adsorption hole 12,
As a result, the die pad 2a comes into close contact with the silicone rubber 1a side. Next, in the plating solution tank 10, 30 ° C. to 50 ° C.
The plating solution stored at a temperature of ° C is supplied to the injection tank 6 by the pressure feed pump 9 via the supply line 21. The plating solution further passes from the injection tank 6 through the injection nozzle 5,
Through hole 4a of mask jig 4 and through hole 3 of mask rubber 3
It is jetted from a to the lead frame 2. In this case, the lead frame 2 is energized with the lead frame 2 as a cathode.

By energizing the lead frame 2 in this manner, the lead frame 2 is plated, and the plated portion 30 is formed on the lower surface of the lead frame 2 (see FIG. 6). In this case, since the die pad 2a of the lead frame 2 can be adsorbed by the die pad adsorption hole 12 and the die pad 2a can be brought into close contact with the silicone rubber 1a, the plating solution does not flow around to the back side of the die pad 2a. Therefore, there is no possibility that the additional plating portion 31 (see FIG. 7) is formed on the back surface side of the die pad 2a.

The plating solution sprayed onto the lead frame 2 then descends to the bottom of the outer tank 15 by its own weight, and the plating solution returns from the bottom of the outer tank 15 into the plating solution tank 10 via the return line 22. Next, the press block 1 rises, and the lead frame 2 is taken out from the mask rubber 3.

As described above, according to this embodiment, the die pad 2 of the lead frame 2 is formed by the die pad suction holes 12.
Since the plating solution is sprayed onto the lead frame 2 while adsorbing a and adhering the die pad 2a to the silicon rubber 1a side, the plating solution does not circulate to the back side of the die pad 2a and the back side of the die pad 2a. Further, the additional plated portion 31 is not formed.

In the above embodiment, the mask jig 3 is provided with the mask rubber 3 and the press block 1 is used.
Although the example in which the silicone rubber 1a is provided is shown, the mask rubber 3 and the silicone rubber 1a are not necessarily provided. When the mask rubber 3 and the silicone rubber 1a are not provided, the die pad suction holes 12 are directly provided on the press block 1.

Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment shown in FIG. 3, an end groove 18 having a relatively large area is provided at the opening end of the die pad suction hole 12 provided in the silicon rubber 1a.
Others are substantially the same as those of the first embodiment shown in FIGS. 1 and 2.

According to this embodiment, the die pad suction holes 12
When the die pad 2a is sucked from the die pad 2a, the die pad 2a is adhered to the peripheral portion by the silicone rubber 1a.
Therefore, the plating solution does not flow around the back surface of the die pad 2a.

Although FIG. 3 shows an example in which the press block 1 is provided with the silicon rubber 1a and the die pad suction holes 12 and the end grooves 18 are provided in the silicon rubber 1a, the press without the silicon rubber 1a is performed. The block 1 may be directly provided with the die pad suction holes 12 and the end grooves 18.

Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment shown in FIG. 4 is one in which a plurality of suction holes 12 are provided for one die pad in the silicon rubber 1a, and the others are the same as those of the first embodiment shown in FIGS. 1 and 2. It is almost the same.

According to the present embodiment, when the die pads 2a are adsorbed from the plurality of die pad adsorption holes 12, the die pads 2a are evenly adsorbed to the silicone rubber 1a,
The die pad 2a is adhered to the silicone rubber 1a without deformation. Therefore, the plating solution does not flow around the back surface of the die pad 2a.

Although FIG. 4 shows an example in which the press block 1 is provided with the silicone rubber 1a and the silicon rubber 1a is provided with the die pad suction holes 12, the silicone rubber 1a is shown.
The die pad suction holes 12 may be provided directly in the press block without providing a.

[0035]

As described above, according to the present invention, since the die pad can be surely brought into close contact with the press block side, when the plating solution is sprayed onto the lead frame, the plating solution wraps around the back surface of the die pad. There is no such thing.
Therefore, it is possible to accurately perform plating only on a predetermined position of the die pad.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a first embodiment of a lead frame plating apparatus according to the present invention.

FIG. 2 is a view showing a press block of a lead frame plating apparatus according to the present invention.

FIG. 3 is an explanatory view showing a second embodiment of a lead frame plating apparatus according to the present invention.

FIG. 4 is an explanatory view showing a third embodiment of a lead frame plating apparatus according to the present invention.

FIG. 5 is a view showing a conventional lead frame plating apparatus.

FIG. 6 is a diagram showing a lead frame plated.

FIG. 7 is a diagram showing a state in which the plating solution still wraps around the back surface of the lead frame.

[Explanation of symbols]

 1 Press Block 2 Lead Frame 4 Mask Jig 5 Injection Nozzle 6 Injection Tank 9 Pressure Pump 10 Plating Solution Tank 11 Vacuum Pump 12 Die Pad Adsorption Hole 13 Communication Passage 15 Outer Tank 16 Groove 18 End Groove 21 Supply Line 22 Return Line

Claims (2)

[Claims] 1. A press for mounting a lead frame having a die pad and having a through hole provided corresponding to the die pad and a lead frame sandwiched between the mask jig and the mask jig. The block includes a block and a spray nozzle that is disposed in the vicinity of the through hole of the mask jig and sprays a plating solution to the lead frame through the through hole. A die pad suction hole is provided on a surface of the press block that abuts against the die pad. This is a lead frame plating device. 2. A step of placing a lead frame having a die pad on a mask jig having a through hole so that the die pad corresponds to the through hole, and the lead frame on the mask jig being a press block. Between the step, the step of sucking the die pad of the lead frame by the die pad suction hole provided in the press block, and the injection nozzle arranged near the through hole of the mask jig,
And a step of spraying a plating solution onto the lead frame through the through holes.