JPH0653387A - Metal mold for correcting semiconductor product - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent lead tip variations and solder adhesion to the top surface of the die when correcting the lead tips of semiconductor products. [Structure] A semiconductor product straightening die is provided with a push pin 12 that presses the center of the upper surface of the product 1, a pad fixing punch 16 that bends down the tips of the leads 2 of the product 1, a pad spring 11, a knockout spring 13, and the like. Upper mold,
A movable die 23 that supports the central portion of the lower surface of the product 1, an air cylinder 31, an upward bending die 21 that upwardly bends the tip ends of the leads 2 of the product 1, a spring 32 that biases the upward bending die 21 toward the movable die 23, It is composed of a lower die provided with a post 19 for guiding the upper die when the die is moved up and down, and the upper bending die 21 is a mechanism capable of sliding to the outer peripheral side of the movable die 23 as the movable die 23 moves downward. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor product straightening die, and more particularly, when it is necessary to prevent the occurrence of variations in the tip of the lead or the adhesion of solder to the upper surface of the die during the straightening of the leads of the semiconductor product. A preferred semiconductor product straightening die.

[0002]

2. Description of the Related Art Conventionally, in order to correct the warp / twist generated in a package of a semiconductor product such as an LSI formed in the previous step, and to bend the lead tip upward or downward, Molds are used, but this kind of mold is
The upper die equipped with push pins for pushing down the four corners of the product package, and the four corners of the product package
It is composed of a movable die for receiving at a location and a lower die with a fixed die for bending the product leads upward.

[0003]

However, in the above-mentioned conventional straightening mold, when warping or twisting occurs in the product package during the molding in the previous step, the lower movable die is used to move the product package 4 By receiving the corners and pushing down the four corners of the product package with the upper push pin, the warp of the package is corrected to a flat state, and the product leads are bent downward / upward. Therefore, even if the flatness of the lead tips on the four sides of the package is uniform at the time of processing (correcting) the product, if the package pressing of the product disappears due to the upward movement of the upper mold after the processing is completed, The sled and twist return to their original state. For this reason, there is a problem that the warp of the lead end of the product is varied in a numerical value close to the amount of warp or twist.

Also, when the lead die tip of the product is bent upward by the fixed die of the lower die of the straightening die, the lead tip portion is likely to slip, which causes solder to adhere to the upper surface of the die. Therefore, when the next product is straightened after the straightening die finishes straightening the solder, solder adheres between the leads of the next product, causing a short circuit phenomenon due to the solder stick. There was a problem.

[0005]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems.
An object of the present invention is to provide a semiconductor product straightening die that can prevent the occurrence of variations in the lead ends of the semiconductor products and the adhesion of solder to the upper surface of the die when the lead ends of the semiconductor products are straightened.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is a semiconductor product straightening gold comprising a main body portion of a semiconductor product and a terminal tip portion around the main body portion to be straightened. An upper die including a push pin that presses a central portion of an upper surface of a semiconductor product, a punch member that bends a terminal end portion of the semiconductor product downward, and a biasing unit that biases the push pin and the punch member downward. A movable die having a tapered surface on the side surface to support the lower surface central portion of the semiconductor product; pressing means for pressing the movable die upward; and a semiconductor provided in contact with the side surface of the movable die. An upper bending die for bending the terminal tip of the product upward, an urging means for urging the upper bending die toward the movable die side, and a guide mechanism for guiding the upper die when the upper die is moved up and down. And a lower mold, Bending die is made of a slidable and configurations to the movable die side outer circumferential side during downward movement of the movable die associated with the downward movement of the upper die.

[0007]

According to the semiconductor product straightening die of the present invention, after the semiconductor product is placed on the movable die of the lower mold, the upper mold is lowered toward the lower mold, whereby the central portion of the upper and lower surfaces of the semiconductor product is lowered. Is clamped by the upper push pin and the lower movable die. As a result, the upper punch member bends the terminal tip of the semiconductor product downward. When the upper die is further lowered, the movable die moves downward, so that the upper bending die, which is in contact with the outer peripheral surface of the side surface of the movable die, resists the urging force of the urging means to the outer peripheral surface of the side surface of the movable die. Slide by the amount of slip at the tip of the terminal. As a result, the terminal tip of the semiconductor product is bent upward. That is, when the terminal tip of the semiconductor product is straightened by the semiconductor product straightening die of the present invention, each terminal tip is fixed without being affected by warpage or twist generated in the semiconductor product at the time of molding in the previous step. Can be flattened without variation. In addition, as in the past, due to the slip generated at the tip of the terminal when the terminal tip of the product was bent upward, the solder adhered to the top surface of the die, and when the next product was straightened, the solder adhered between the terminals, causing a short circuit phenomenon. The trouble that causes it can be eliminated.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 are configuration diagrams of an upper die and a lower die which compose a semiconductor product straightening die of this embodiment, and the pre-process shown in FIG. 4 is performed by the upper die and the lower die of the straightening die. The upper and lower surface central parts of the product 1 which has been molded in step 1 are clamped and a predetermined pressing force is applied to correct the tips of the leads 2 of the product 1.

The structure of this embodiment will be described in more detail. Upper mold bushes 4 are press-fitted into the four corners of the lower surface of an upper mold holder 3 which constitutes the upper mold of a semiconductor product straightening mold. A lower mold post (described later) is inserted into each upper mold bush 4. A hanger 9 is fixed to the upper surface of the upper die holder 3, and the hanger 9 is connected to a press cylinder operated by operating a press lowering switch and a press raising switch. Further, inside the hole formed in the upper die holder 3, the pad spring 1 serving as a biasing means is provided.
1 and a knockout spring 13 are provided.

Further, four upper die stoppers 5 and a punch holder 14 are fixed to the lower surface of the upper die holder 3, and a pad 8 and a product 1 are provided below the punch holder 14. And a pad fixing punch 16 which is a punch member for bending the lead downward. Punch holder 1
4, the push pin 12 is inserted through the center of the pad 8, and the pad fixing punch 16, while the pad support member 33 is inserted through both sides of the punch holder 14 via the pad bush 15. It is inserted into Pat 8. Further, four upper pad stoppers 6 and four pad posts 7 are arranged on the lower surface of the pad 8. In this case, the knockout spring 13 urges the push pin 12 downward while
1 urges the pad 8 downward.

On the other hand, posts 19 as guide mechanisms are vertically provided at four corners of the upper surface of a lower die holder 24 constituting a lower die of a semiconductor product straightening die, and each post 19 is
The upper die holder 3 is guided through the upper die bush 4 when the upper die holder 3 is moved up and down. Further, an air cylinder 31 as a pressing means is arranged inside the hole formed in the central portion of the lower die holder 24, while four lower die stoppers 20 are provided on the upper surface portion of the lower die holder 24. The upper die holder 3 is arranged so as to come into contact with each of the four upper die stoppers 5 when the upper die holder 3 descends. Further, the die backing 26, the die frame 22, the upward bending die 21 for upwardly bending the leads of the product 1, the bending die frame 30, and the product 1 are placed on the upper surface of the lower die holder 24. And a movable die 23 for

The movable die 23 is formed with a taper portion on the outer periphery of the side surface, is slidable in the up-down direction inside the upward bending die 21 and the die frame 22, and at the same time, the die fixing bolt 2 is provided.
7 is connected to the air cylinder 31. Further, on the upper surface of the die frame 22, four lower pad stoppers 18 are provided.
Are arranged so that each of the four upper mold pad stoppers 6 comes into contact with each other when the upper mold holder 3 moves downward. Further, a spring 32 and a set screw 29, which are biasing means for pressing the four side portions of the upper bending die 32, are arranged on the four side portions of the upper bending die 21, and an upper surface portion of the upper bending die 21 is The lid 17 is attached. Further, an air intake 25 is arranged at the end of the lower mold holder 24.
In this case, when the air supply is stopped, the movable spring 28
By the action, the die fixing bolt 27 is lowered, so that the movable die 23 is also lowered.

Next, the operation of straightening the leads of the product with the semiconductor product straightening die of the present embodiment having the above-described structure will be described.

First, after air is supplied to the air inlet 25 of the lower die holder 24 constituting the semiconductor product straightening die, the product 1 formed in the previous step on the upper surface of the movable die 23 of the lower die holder 24. To place. Next, when the press lowering switch is operated, the press cylinder operates, and as a result, the upper die holder 3
Is the post 19 of the lower mold holder 24 via the upper mold bush 4.
Guided by, the descent operation is started. In this case, when the upper die pad stopper 6 and the lower die pad stopper 18 are in contact with each other due to the lowering operation of the upper die holder 3, the rising pressure of the operating air cylinder 31 is increased by the pad spring 11 of the upper die holder 3. It is set to be stronger than the downward bias.

As shown in FIG. 2, the lower end of the push pin 12 of the upper die holder 3 is moved by the lowering operation of the upper die holder 3.
The upper part of the package of the product 1 placed on the upper surface of the movable die 23 of the lower die holder 24 is pressed, and the lower end of the pad fixing punch 16 pushes down the lead tip of the product 1. In this case, since the urging force of the pad spring 11 is set to be stronger than the bending stress of the leads 2 on the four sides of the product 1, the lead tips of the product 1 are bent downward by the set amount. Further, when the upper die holder 3 is moved downward, the biasing force of the push pin 12 is set to be stronger than the rising pressure of the air cylinder 31 and the biasing force of the spring 32 pressing the four sides of the upper bending die 21. Therefore, as shown in FIG. 3, the product 1 descends and separates from the pad fixing punch 16.

As the upper die holder 3 descends, the movable die 23 of the lower die holder 24 slides downward inside the upper bending die 21 via the taper portion of the outer periphery of the movable die. It slides laterally (left and right in FIG. 3) by the amount of slip of the lead tip portion against the biasing force of 32. In this case, the correction amount of the lead 2 of the product 1 on the movable die 23 is such that the bottom portion of the movable die 23 that slides downward from the position where the tip of the lead is in contact with the upper surface of the upward bending die 21 is the die backing 26. This corresponds to the stroke up to the position where the upper die holder 3 and the lower die stopper 20 of the lower die holder 24 contact each other, that is, the entire semiconductor product straightening die. The correction of the lead 2 of the product 1 is completed at the bottom dead center of.

When the supply of air from the air intake 25 of the lower die holder 24 is stopped with the completion of the lead straightening operation of the product 1, the die fixing bolt 27 is lowered by the action of the movable spring 28, and accordingly the movable die 28 is moved. The die 23 also descends. Next, when the press up switch is operated, the press cylinder operates, and as a result, the upper die holder 3 in the state shown in FIG.
Starts to rise while being guided by the post 19 of the lower die holder 24, and rises to a predetermined rising end position. Thereafter, after the product 1 is taken out from the upper surface of the movable die 23 of the lower die holder 24, air supply is restarted from the air inlet 25 of the lower die holder 24, and the lead straightening of the next product is performed in the same manner as above. I do.

As described above, according to the semiconductor product straightening die of this embodiment, the central portion of the product package is held by the push pin 12 of the upper die holder 3 and the movable die 23 of the lower die holder 24, and At the time of downward bending and upward bending of the lead tip end portion, the taper portion of the movable die 23 of the lower die holder 24 slides the upper bending die 21 in the lateral direction, so that the lead tip end portion of the product is slid down and bent. Since it is a mechanism that bends upward, when correcting the lead tip of the product with the mold, the lead tip on the four sides of the product is not affected by the warp or twist generated in the previous process (during molding). Can be corrected to be flat without variation.

Further, according to the semiconductor product straightening die of this embodiment, as in the conventional case, a slip occurs at the lead tip portion when the lead tip portion of the product is bent upward, which causes solder to adhere to the upper surface of the die. However, it is possible to solve the problem that the solder adheres between the leads and causes a short circuit phenomenon when the next product is straightened.

[0021]

As described above, according to the semiconductor product straightening die of the present invention, the central portion of the main body of the semiconductor product is sandwiched by the upper push pin and the lower movable die, and the semiconductor product is held. At the time of downward bending and upward bending of the terminal tip of, the upper bending die slides laterally by the taper part of the lower movable die, so that the downward bending and upward bending can be performed while sliding the terminal tip of the semiconductor product. Since the mechanism that does this is used, when correcting the terminal tip of the semiconductor product, each terminal tip around the semiconductor product is not affected by the warp and twist that occurred in the semiconductor product during the molding in the previous process. It is possible to straighten the parts without variation, and moreover, as before, solder adheres to the top surface of the die due to the slip that occurs at the terminal tips when the product is bent upward. , It is possible to obtain such can eliminate the problem of adhering the solder to between the terminals when straightening the next product causing a short circuit phenomenon, various remarkable effects.

[Brief description of drawings]

FIG. 1 shows a configuration of a semiconductor product straightening die according to an embodiment of the present invention, FIG. 1 (A) is a plan view of an upper mold, and FIG. 1 (B) is a plan view of a lower mold.

FIG. 2 is a cross-sectional view of the semiconductor product straightening die of this embodiment when the upper die is lowered.

FIG. 3 is a sectional view of the semiconductor product straightening die of this embodiment at the time of bottom dead center of the upper die.

FIG. 4 shows a configuration of a semiconductor product of this embodiment, and FIG.
4A is a plan view, FIG. 4B is a front view, and FIG. 4C is a right side view.

[Explanation of symbols]

 1 product 2 lead 3 upper die holder 5 upper die stopper 6 upper die pad stopper 8 pad 12 push pin 14 punch holder 16 pad fixing punch 18 lower die pad stopper 19 post 20 lower die stopper 21 upper bending die 22 die frame 23 movable die 24 Lower mold holder 26 Die backing 31 Air cylinder

Claims (1)

[Claims] 1. A semiconductor product straightening die configured to hold a main body of a semiconductor product and straighten a terminal tip portion around the main body, and a push pin for pressing a central portion of an upper surface of the semiconductor product. An upper die provided with a punch member for bending the terminal tip of the semiconductor product downward, and an urging means for urging the push pin and the punch member downward, and a center of the lower surface of the semiconductor product with a tapered surface formed on a side surface portion. A movable die for supporting the movable die, pressing means for pushing the movable die upward, an upward bending die for bending the terminal tip of the semiconductor product upward, which is disposed in contact with the side surface of the movable die, The upper bending die comprises a lower die including an urging means for urging the upper bending die toward the movable die side, and a guide mechanism that guides the upper die when the upper die is moved up and down. The movable die accompanying the lowering movement of the upper die (A) A semiconductor product straightening die, which is slidable to the outer peripheral side of the movable die side face when the lower die is moved.