JPH08118299A - Deburring device for lead frame - Google Patents

Abstract

PURPOSE: To provide a deburring device which can surely remove the side burrs of a lead frame through the contact of the lead frame side edge with the deburring means arranged on the side along the conveyance direction, accompanied with the conveyance of the lead frame. CONSTITUTION: Along the conveyance direction of a lead frame 10, a deburring mechanism 3 for removing the side burrs 21 on the side surface 10a of the lead frame 10 is arranged. The deburring mechanism 3 is installed on a guide rail 2 or other member, and makes contact with the side surface 10a of the lead frame 10 to be conveyed, and the side burrs 21 are scraping-removed. The deburring mechanism 3 may have a hook shape, brush shape, roller shape, etc., and scraping-removes the side burrs 21 through the contact with the side surface 10a. Further, the mechanism 3 may be installed on both the sides of the guide rail 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 deburring device for removing resin burrs attached to a lead frame after a molding process.

[0002]

2. Description of the Related Art When a semiconductor device is manufactured by using a lead frame, a chip-shaped semiconductor element is mounted on a die pad of the lead frame, and then an electrode pad of the semiconductor element and an inner lead of the lead frame are bonded via a bonding wire. Connecting. Thereafter, the semiconductor element and the bonding wire on the lead frame are integrally sealed with a molding resin by the transfer molding method, and the outer leads of the lead frame are cut and processed to complete individual semiconductor devices.

In a molding process in which a semiconductor element and a bonding wire are integrally sealed with a molding resin, a lead frame on which the semiconductor element is mounted and the bonding wire is connected is sandwiched between an upper mold and a lower mold. ,
A mold resin is transferred and filled into the cavity provided between the upper and lower molds to seal the semiconductor element and the bonding wire.

At this time, there occurs a phenomenon that the mold resin leaked from the gap between the upper mold and the lower mold becomes a resin burr and adheres to the lead frame. FIG. 3 is a plan view illustrating how resin burrs adhere. The resin flash includes a side flash 21 mainly attached to the side surface 10a of the lead frame 10 and a flash flash 22 attached between the semiconductor device 11 and the tie bar 10b. The side flash 21 is left on the gate portion of the mold when the mold resin is transferred and filled in the cavity, and the flash flash 22 is the tie bar 10.
It is the one to which the mold resin in front of which is dammed by b is attached.

Such a resin burr is used for the lead frame 10.
If the outer lead 10c is attached to the
Various inconveniences occur in the plating process on the outer lead 10c and the cutting and processing of the outer lead 10c (trim-form process). For example, when the resin burr is peeled off after the outer lead 10c is plated, the plated portion is peeled off to expose the base material of the lead frame 10 and the outer lead 1
0c impairs solder wettability and corrosion resistance. Further, in the trim-foam process, if the peeled resin flash remains at the press position of the lead frame 10, it will be a dent and will be scratched during press working.

In order to prevent such an inconvenience from occurring, it is necessary to remove the resin burrs adhering to the lead frame after the molding process when manufacturing a semiconductor device. FIG. 4 is a flowchart illustrating the processing from resin deburring to lead processing. First, before the resin deburring, the pretreatment shown in step S1 is performed. The pretreatment is a treatment for dipping the lead frame in an alkaline treatment solution or an acidic treatment solution to chemically swell the resin burr, and then floating the resin burr by electrolytic treatment.

Next, with the resin flash floating, the hydraulic deburring process shown in step S2 or the liquid honing process shown in step S3 is performed. The water deburring process is a process that removes resin flash by injecting high-pressure water from a nozzle arranged above the lead frame, and the liquid honing process sprays water mixed with plastic particles and glass beads onto the lead frame at a predetermined pressure. Is a process for removing resin flash.

After removing the resin burr adhering to the lead frame by this, the outer lead exterior is plated by the plating process shown in step S4, and then trim-form process is carried out as the lead process shown in step S5. Note that step S2 and step S3
In any of the deburring processes shown in (1), a deburring device that ejects liquid from a nozzle arranged above the lead frame is used. The deburring device includes a transport mechanism for transporting the lead frame and a nozzle for ejecting high-pressure liquid, and is configured to remove the resin burrs adhering to the lead frame.

[0009]

However, in such a lead frame deburring apparatus, a guide rail which is a part of the lead frame carrying mechanism holds the periphery of the side surface of the lead frame along the carrying direction. It is arranged in a state. For this reason, the side flash that adheres to the side surface of the lead frame is hidden inside the guide rail,
The liquid ejected from the nozzle does not hit the side flash sufficiently and it is difficult to remove it. If the side burr remains,
It may fall off during transportation in a later step or cause conduction failure during plating. Therefore, it is an object of the present invention to provide a deburring device for a lead frame that reliably removes the side flash.

[0010]

SUMMARY OF THE INVENTION The present invention is a deburring device for a lead frame, which is made to achieve the above object. That is, the present invention is a deburring device for a lead frame that conveys a lead frame after a molding process and sprays a high-pressure liquid onto the lead frame to remove resin burrs adhering to the lead frame. Deburring means for contacting the side surface of the frame along the transport direction is provided.

[0011]

In the present invention, since the deburring means is provided which comes into contact with the side surface of the lead frame along the carrying direction as the lead frame is carried, the deburring means is used when carrying the lead frame. It will be in a state of contacting with, and the side burr adhering here will be scraped off.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a deburring device for a lead frame according to the present invention will be described below with reference to the drawings. FIG. 1 is a view for explaining an embodiment of the deburring device of the present invention,
(A) is a plan view and (b) is a sectional view. The deburring device 1 in this embodiment is arranged above the lead frame 10 and a guide rail 2 for carrying and holding the lead frame 10 after the molding process, a deburring mechanism 3 attached to the guide rail 2, for example. The nozzle 4 is provided.

Usually, the lead frame 10 has a plurality of semiconductor devices 11 (sealed in a mold resin).
Is provided and is conveyed into the deflashing device 1 after the molding process. On the side surface 10a of the lead frame 10 along the carrying direction, side burrs 21 generated in the molding process are formed.
However, there is a flash flash 22 on the inside,
In this state, it is conveyed into the deflashing device 1. The guide rail 2 is a side surface 1 of the lead frame 10.
It is arranged to hold the periphery of 0a, and the side burr 21 is hidden inside the guide rail 2 during transportation.

The deburring mechanism 3 is provided with a side surface 10a of the lead frame 10 as the lead frame 10 is conveyed.
The side flash 21 is scraped off by this contact. Therefore, the deburring mechanism 3 is attached to a fixed position, for example, the guide rail 2 or other member, and the side surface 1 is moved by the conveyance of the lead frame 10.
The contact with 0a is obtained. FIG. 1 (a)
In the example shown in (1), the deburring mechanism 3 is attached to the lower side of the guide rail 2 in the carrying direction, and when the lead frame 10 is carried out, it comes into contact with the side surface 10a and scrapes off the side flash 21. .

The deburring mechanism 3 has a claw shape as shown, a brush shape (not shown), and a roller shape (not shown).
Various forms are conceivable. In any case, any mechanism may be used as long as it can come into contact with the side surface 10a of the lead frame 10 when it is conveyed and scrape off the side burr 21.

Although FIG. 1A shows an example in which the deburring mechanism 3 is provided on one side of the guide rail 2, both of the lead frames 10 provided on both sides of the guide rail 2 are shown. The side surface 10a may be in contact with the side surface 10a. Normally, the side burr 21 is formed by adhering the resin remaining on the gate portion (not shown) of the mold used in the molding process to the lead frame 10, and thus the side burr 21 is formed on one side surface 10 a of the lead frame 10. The deburring mechanism 3 in contact can be used. But,
Depending on the direction in which the lead frame 10 is transported,
In some cases, it may not be possible to specify on which side surface 10a of the lead frame 10 the side flash 21 exists. Therefore,
If the deburring mechanism 3 is provided on both of the guide rails 2, it is possible to cope with the side flash 21 on any of the side surfaces 10a of the lead frame 10.

In order to remove the resin burrs on the lead frame 10 by using the deburring device 1, the lead frame 10 after the molding process is pretreated,
After the resin flash has been swelled and floated, it is conveyed into the flash removing apparatus 1 in this embodiment. As a result, the lead frame 10 is transported along the guide rails 2 and placed at a predetermined position.

In this state, high-pressure water or a liquid containing an abrasive is jetted from the nozzle 4 to remove the resin flash adhered to the lead frame 10. At this time, the lead frame 10
Since the high pressure water or the solution is sufficiently hit on the flash beam 22 attached to the upper part, the flash beam 22 is easily peeled off. On the other hand, since the side burr 21 is hidden in the guide rail 2, the high pressure water or the solution is not sufficiently hit and the side burr 21 is insufficiently removed at this stage.

Next, the lead frame 10 is conveyed along the guide rail 2 and moved to the next position.
During this conveyance, the deburring mechanism 3 described above comes into contact with the side surface 10a of the lead frame 10, and the side flash 21 left unremoved by the high-pressure water or solution jetting.
Will be scraped off.

FIG. 2 is a view showing the removal rate of the side deburring when the deburring device 1 in this embodiment is used,
(A) is a SOP-24pin type lead frame 1
In the case of 0, (b) shows the case of the SDIP-48pin type lead frame 10. In addition, each numerical value is the number of side burrs and the removal rate examined for 10 lead frames 10 of each type.

In the case of the SOP-24pin type lead frame 10 shown in FIG. 2A, the number of side burrs before processing is 240 in both the conventional and the present embodiment. On the other hand, regarding the number of side burrs after the treatment, the removal rate is 225 in the conventional case and the removal rate is 6.25 (%), and in the present embodiment, the removal rate is 0 (all removed) and the removal rate is 100 (%). .

In addition, SDIP-48p shown in FIG.
In the case of the in-type lead frame 10, the number of side flashes before processing is 70 in both the conventional and the present embodiments. On the other hand, the number of side burrs after treatment is 6
5, the removal rate is 7.1 (%), and in the present embodiment, the removal rate is 0 (all removed) and the removal rate is 100 (%). In any case, it can be seen that the side flash 21 of the lead frame 10 can be completely removed by using the flash removing apparatus 1 of this embodiment as shown in FIG.

In order to prevent the side burr 21 scraped off by the deburring mechanism 3 from adhering to the lead frame 10 again, that is, during transportation, that is, the side burr 21.
Even when removing the water, a water or a solution (not necessarily high pressure in this case) is jetted from the nozzle 4 to remove the scraped side burr 21 to the lower side of the deburring device 1 (a discharging mechanism (not shown)). It is desirable to drop it completely.

[0024]

As described above, the deburring device for a lead frame of the present invention has the following effects.
That is, in the present invention, the deburring mechanism that comes into contact with the side surface of the lead frame when it is transported makes it possible to reliably remove the side flash that is hidden in the guide rail. As a result, the side burr does not fall off in the subsequent process, and it is possible to reliably obtain conduction during the plating process, and it is possible to significantly reduce the occurrence of dents during press working in the trim-form process. Become.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an embodiment of a deburring device of the present invention, (a) is a plan view and (b) is a sectional view.

FIG. 2 is a diagram showing a removal rate of a side flash, in which (a) is SO.
In case of P-24pin type, (b) is SDIP-48
This is the case of the pin type.

FIG. 3 is a plan view illustrating how resin burrs are attached.

FIG. 4 is a flowchart from resin deburring to lead processing.

[Explanation of symbols]

 1 Deburring Device 2 Guide Rail 3 Deburring Mechanism 4 Nozzle 10 Lead Frame 10a Side 11 Semiconductor Device 21 Side Burr 22 Flash Burr

Claims (1)

[Claims] 1. A deburring device for a lead frame, which conveys a lead frame after a molding step, and sprays a high-pressure liquid onto the lead frame to remove resin burrs adhering to the lead frame. A deburring device for a lead frame, comprising deburring means that comes into contact with a side surface of the lead frame along the carrying direction.