JP3216932B2 - Molding device for external lead modification of semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding apparatus for modifying external leads of a semiconductor device.

[0002]

2. Description of the Related Art A resin-encapsulated semiconductor device is commercialized through several steps such as tie bar cutting and lead forming after a semiconductor element is mounted on a stage portion of a lead frame and resin-molded. Due to the increasing number of multi-pin products in recent semiconductor devices and the tendency of resin moldings to become larger and shrinking and deforming of the resin, the bending accuracy of external leads after bending, especially external leads The coplanarity of the joint portion with the substrate has become a problem. This is because if the lead floats from the mounting surface during mounting, a product defect such as a connection error may be caused. For this reason, the bending accuracy of the lead is required to be extremely high, and after bending the external lead using a bending punch, the external lead is used to correct variations in the height position of the lead tip. May be modified. Further, when the external lead collides with a foreign substance or is deformed when the product is transported, it may be necessary to modify and bend the external lead with high precision.

The present applicant has previously proposed a method of modifying and bending a lead in a free state as shown in FIG. 14 in order to improve the bending accuracy of the external lead 2 of the semiconductor device 1 (Japanese Patent Application No. 2-169520). ). In this method, the base position of the external lead 2 is supported by the receiving die 100 and the knockout 102, and the distal end of the external lead 2 is released from the die 100 and is free, and the distal end of the external lead 2 is pushed down and pressed by the punch 104. In this way, the variation of the tip of the external lead 2 is corrected. The present applicant has also proposed a modified bending method of the external lead 2 as shown in FIG. 15 (Japanese Patent Application No. 3-132100). According to this method, after bending the external lead 2, the upper surface 3 of the resin mold portion of the semiconductor device 1 is brought into contact with the support die 106 to regulate the position of the semiconductor device 1 and free the base position of the external lead 2. In this state, the modified bending punch 108 is pressed against the lower surface of the lead tip which comes into contact with the mounting board to correct the variation of the lead tip. By applying the modified bending method shown in FIGS. 14 and 15 to one semiconductor device, the bending accuracy of the external lead can be further improved.

[0004]

However, in order to perform the modified bending by pushing and bending the external lead in both the upper and lower directions,
Driving the push-down punch 104 and the modified bending punch 108
The reciprocating drive of the two punches needs to be controlled appropriately with a certain timing, so that it takes a long time for one retouching. In addition, there is a problem that the control device becomes complicated. SUMMARY OF THE INVENTION An object of the present invention is to provide a molding apparatus for external lead modification of a semiconductor device, which can modify and bend the external lead with high precision, is simple in control, and can efficiently perform the modified bending.

[0005]

The present invention has the following arrangement to achieve the above object. That is, according to the molding device for external lead modification of a semiconductor device of the present invention, the semiconductor device has a fixed plate and a movable plate that can reciprocate in a direction of coming and going to and from the fixed plate. An external lead projecting mold for bending and modifying an external lead projecting from the semiconductor device at a predetermined angle, the die having an end face for receiving a resin sealing portion of the semiconductor device, and a hole formed in the fixing plate. The fixed board side support, which is always elastically supported so that the front end surface thereof protrudes from the surface of the fixed board and is movable inward in the fixed board when a predetermined or more pressing force is applied from the movable board side. A base and a hole formed in the movable platen side, a tip end surface of which is always protruded from the surface of the movable platen side and is movably supported in opposition to the fixed platen-side pedestal. When moved in the lateral direction, the front end surface comes into contact with the resin sealing portion and A movable platen holding member for holding the semiconductor device, a stripper elastically supported on the movable platen at a predetermined distance to the fixed platen side, and provided to be movable toward and away from the movable platen; A first bending punch that is provided on a side of the fixed plate of the stripper and abuts on an external lead of the semiconductor device held between the fixed plate side receiving base and the movable plate side holding member, and bends the external lead toward the fixed plate; A first stopper for restricting the stripper and the fixed plate from coming closer than a predetermined distance, and a tip end surface abutting on the other surface of the resin sealing portion of the semiconductor device; The movable platen is provided on the movable plate so as to face the table, the stripper is closest to the fixed platen, and the movable platen is further fixed to the fixed platen while the semiconductor device is held between the fixed platen-side pedestal and the movable-side holding member. When approaching the semiconductor device, A presser that presses and moves the semiconductor device and the fixed board side base inwardly of the fixed board; and a second stopper that regulates the fixed board and the movable board so that the movable board does not come closer than a predetermined distance. It is provided on a fixed platen, and when the fixed platen-side pedestal is moved in the fixed platen direction in a state where the semiconductor device is held between the presser and the fixed platen-side pedestal, the semiconductor device is relatively protruded, A second bending punch that abuts on the lead and bends the external lead toward the movable platen.

[0006]

According to the molding apparatus for external lead modification of a semiconductor device according to the present invention, during the operation of moving the movable plate so as to approach the fixed plate, first, the fixed plate side receiving base and the movable plate side The semiconductor device is suitably held by the holding member, and the first bending punch provided on the stripper comes into contact with the external lead from one side, and the external lead can be bent toward the fixed board. Subsequently, the semiconductor device is held by the presser provided on the movable plate opposite to the fixed platen-side receiving base and the fixed platen-side receiving portion, and the second bending punch abuts on the external lead,
The external lead can be bent toward the movable platen. That is, the external lead can be bent in two opposite directions by one drive of the movable plate. Thereby, the external lead can be modified and bent efficiently and with high precision.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing one embodiment of a molding device for external lead modification of a semiconductor device according to the present invention. Reference numeral 10 denotes a fixed plate, which in this embodiment constitutes a part of a fixed lower die fixed to the press bed 15 as shown in FIG. The fixed platen 10 is fixed to a die bed 14 via a backing plate 12, and the die bed 14 is fixed to a press bed 15. Reference numeral 16 denotes a movable plate,
Reciprocally fits on a guide shaft 18 erected on the upper surface, and constitutes a part of an upper die which is a movable die which can reciprocate in a direction of coming and coming from the fixed platen 10.

Reference numeral 20 denotes a stationary platen-side pedestal, which has a tip end surface which contacts the lower surface of the resin sealing portion of the semiconductor device and supports the semiconductor device, and which reciprocates in a hole formed in the stationary platen 10. It is fitted as possible. The fixed platen-side pedestal 20 is provided with a die bed 1
4 is connected to a piston 24 reciprocally movable in a vertical direction in a cylinder 22 provided in the cylinder 4, and the distal end surface always projects from the surface of the fixed platen. That is, compressed air is introduced into the lower cylinder chamber of the cylinder 14, and the piston 24 is urged to project the fixed platen-side pedestal 20 upward at a predetermined pressure. And the air pressure is
The predetermined pressure is set such that the fixed platen-side pedestal 20 moves inward of the fixed platen 10 when a predetermined or more pressing force is applied from the movable platen 16 side.

Reference numeral 26 denotes a movable platen-side holding member which is in contact with the other surface of the resin sealing portion of the semiconductor device,
A front end surface for holding the semiconductor device between the front end surface of the movable plate 16 and a hole formed in the movable plate 16, the backing plate 28 fixed to the movable plate 16, and the pressing element 30 so as to be reciprocally movable. Have been. The movable platen-side holding member 2
6, the tip surface protrudes from the tip surface of the presser 30 by its own weight at all times (when the mold is opened), and when a predetermined or more pressing force is applied from the fixed plate 10 side, the movable plate 16 side inward. And is elastically received by the first spring 32. When the distal end surface of the movable platen-side holding member 26 protrudes due to its own weight, the flange formed at the upper end is engaged with the step of the hole provided in the backing plate 28, and There is a predetermined slight gap 36 between the upper end surface of the board-side holding member 26 and the washer 34 that receives the first spring 32.

Reference numeral 38 denotes a stripper, which is elastically moved by a second spring 40 at a predetermined distance from the punch plate 48 fixed to the movable plate 16 via the backing plate 28 toward the fixed plate 10 (downward in the drawing). Supported,
The movable plate 16 is provided so as to be movable toward and away from the movable plate 16. 42
Denotes a first bending punch, and a fixing plate 1 of the stripper 38.
0, which is provided on the side surface (lower surface) and abuts against an external lead of the semiconductor device held between the fixed platen-side pedestal 20 and the movable platen-side holding member 26, and moves the external lead toward the fixed platen 10 (downward). Can be bent. Reference numeral 44 denotes a first stopper, which protrudes downward from the lower surface of the stripper 38 and can restrict the movement of the stripper 38 so that the stripper 38 and the fixed board 10 do not approach each other more than a predetermined distance. Reference numeral 45 denotes an adjustment liner, which is provided to adjust the height of the first stopper 44.

Numeral 30 denotes a pressing element, which is used as the stationary platen-side support 2.
The movable plate 16 projects downward from the movable plate 16 via a backing plate 28 so as to face the movable plate 0. The pressing element 30 is slidably fitted in a through hole at a central portion passing through the stripper 38 and the first bending punch 42. The pressing element 30
In the state where the stripper 38 is closest to the fixed platen 10 and the semiconductor device is held between the fixed platen-side pedestal 20 and the movable-side holding member 26, the movable platen 16 is further close to the fixed platen 10. At the time of lowering, the semiconductor device and the fixed platen base 20 are brought into contact with the upper surface of the resin sealing portion of the semiconductor device and the fixed platen 10 against the urging force of the piston 24 by the compressed air.
It can be pressed and moved inward.

Reference numeral 46 denotes a second stopper, which is a punch plate which penetrates through holes formed in the stripper and is fixed to the movable platen 16 via the backing plate 28.
The fixed plate 10 and the movable plate 16 are regulated so as not to be closer than a predetermined distance. 5
Reference numeral 0 denotes a second bending punch, which is provided on the fixed platen 10, and in which the fixed platen-side pedestal 20 moves in the fixed platen 10 while the semiconductor device is held between the presser 30 and the fixed platen-side pedestal 20. When the semiconductor device is moved to the position above, the semiconductor device can bend toward the movable plate 16 (upward) by contacting the external lead of the semiconductor device.

Next, the operation of the embodiment of FIG. 1 will be described with reference to the sectional views of FIGS. As shown in FIG. 2 (A), the semiconductor device 1 is supplied to the upper surface of
After being mounted, the movable platen 16 is lowered from above by the press ram 17. As a result, first, the distal end surface of the movable platen-side holding member 26 abuts on substantially the center of the upper surface of the resin sealing portion of the semiconductor device 1, and the semiconductor device 1 is brought into contact with the fixed platen-side pedestal 20 and the movable platen-side holding member 26. It is sandwiched and held. At this time, the fixed platen-side pedestal 20 is located at the top dead center by the piston 24 urged by the compressed air. That is, the urging force of the compressed air urging the fixed platen support 20 upward through the piston 24 is greater than the urging force of the first spring 32. At this point, the first bending punch 42 is not in contact with the external lead 2 of the semiconductor device 1 as shown in FIG. Has become.

Next, the movable platen 16 is further lowered, so that the first bending punch 42 as shown in FIG.
Contact the external leads 2 of the semiconductor device 1. And
In the first bending punch 42, the first stopper 44 is fixed to the fixed platen 1.
0, and the external lead 2 is bent downward as shown in FIG. At this time as well, the fixed platen-side pedestal 20 is located at the top dead center by the piston 24 urged by the compressed air. At this time, the distal end surface of the pressing element 30 is not in contact with the upper surface of the resin sealing portion of the semiconductor device 1.

When the movable platen 16 is further lowered, the stripper 38 resists the urging force of the second spring 40 and moves relative to the movable platen 16 in a direction approaching as shown in FIG. Move. Further, the pressing element 30 descends together with the movable plate 16, and the tip end face of the pressing element 30 contacts the upper surface of the resin sealing portion of the semiconductor device 1, and
Is lowered against the pressure of the compressed air introduced into the cylinder 22. In other words, the downward pressure of the movable platen 16 exceeds the pressure of the compressed air that urges the fixed platen pedestal 20 upward to support the semiconductor device 1 from below, and the fixed platen pedestal 20 is lowered. . Then, as shown in FIG. 4 (B), the second bending punch 50 rises relatively to the fixed platen support 20, and contacts the external lead 2 from below on the upper surface, and raises the external lead 2 upward. Bend. The upper modified bending is performed until the second stopper 46 comes into contact with the surface of the fixed board 10. In order to more precisely provide the flatness of the lower surface of the external lead 2, the lower bending amount of the external lead 2 is adjusted by adjusting the thickness of the adjustment runner 45 in relation to the next upper bending amount. Trial molding is performed for each of the lead frames, and is finally determined. The reason for this adjustment is that the processing on the lead frame is performed by pressing and molding, and the desired flatness can be obtained by trial molding with the first few samples.

When the upper correction bending is completed, first, the air pressure of the air cylinder 22 in the die head 14 is released to the atmosphere.
Thereafter, the movable platen 16 is returned upward, and the semiconductor device for which the formation of the external leads 2 has been completed is taken out by a suction device or the like. Alternatively, when the upper correction bending is completed, compressed air of the same pressure is supplied to the upper and lower ports of the cylinder 22 so that the piston 24 is stopped without vertical movement, and then the movable platen 16 is returned upward and the external lead 2 The molded semiconductor device may be taken out by a suction device or the like. Activating the piston 24 in this manner means that, when the movable plate 16 is lowered to perform the lower correction bending and the upper correction bending, and there is a pressure in the cylinder 22 that acts to raise the piston 24, the movable plate 16 As the piston rises, the piston 24 also rises and pushes up the semiconductor device 1, and the external lead 2 bent upward is bent again to the first position.
This is because it is deformed downward by the bending punch 42.

As described above, only by lowering the movable platen 16, the external lead 2 can be once bent downward and upward, and highly accurate reshaping can be performed. At this time, since only the movable platen 16 is lowered, the operation of the molding apparatus is very simple, and the processing efficiency can be greatly improved. In addition, in the state of FIG. 4, when the fixed platen-side pedestal 20 is slightly moved downward and the upward movement of the movable platen 16 is delayed, the stress of the pressed resin sealing portion is released, and The device 1 can return to a shape close to a state where it is mounted on a substrate. At this time, the semiconductor device 1 is preferably pressed downward from above by the movable platen-side holding member 26, whereby the external leads 2 can be formed into the same appropriate shape as when mounted on the board. .

By the way, after the external lead 2 is modified and formed, the movable plate 16 is moved upward to open the mold.
The semiconductor device 1 jumps up due to the springback force. In contrast, according to the present embodiment, FIG.
Since there is a gap 36 between the upper end of the movable platen-side holding member 26 and the washer 34 as in the state of the above, the movable platen-side holding member 26 can suitably press the semiconductor device 1 by its own weight at the moment when the mold is opened. Therefore, the semiconductor device 1 can be prevented from jumping.

Next, referring to FIG. 5, another embodiment of the molding apparatus for modifying external leads according to the present invention will be described. In this embodiment, the first bending punch 4 of the embodiment of FIG.
A roller 52 is provided in place of the roller 2. As shown in FIG. 5, the roller 52 is rotatably disposed at the lower end of the stripper 38, and includes a backup roller 5 composed of a bearing.
4 is supported in contact with the outer peripheral surface. This roller 52
According to the above, when performing modified bending in contact with the external lead 2,
By the rotation, the surface of the external lead 2 can be suitably bent without damaging it.

Next, the operation of the embodiment of FIG. 5 will be described with reference to FIGS. As shown in FIG. 6, the semiconductor device 1 transported by the suction transport device 56 is placed on the upper surface of the fixed platen-side pedestal 20 with the mold opened. Next, the upper die including the movable platen 16 is lowered, and as shown in FIG. 7, the movable platen-side holding member 26 first comes into contact with the upper surface of the resin sealing portion of the semiconductor device 1, and the semiconductor device 1 is fixed to the fixed platen. It is held between the side stand 20. As shown in FIG. 8, the upper die is further lowered, and the lower lead bending of the external lead 2 starts. When the first stopper 44 projecting from the lower surface of the stripper 38 comes into contact with the upper surface of the fixed platen 10, the lower reshaping bending is completed. Then, as shown in FIG. 9, the pressing element 30 abuts on the upper surface of the resin sealing portion of the semiconductor device 1, and holds the semiconductor device 1 between the semiconductor device 1 and the fixed platen-side pedestal 20. When the movable plate 16 is further lowered while holding the semiconductor device 1 in this way, the fixed platen-side pedestal 20 is lowered. Then, as shown in FIG. 10, the second bending punch 50 is used until the second stopper 46 projecting from the lower surface of the punch plate 48 comes into contact with the surface of the fixed plate 10.
The upper lead is modified and bent. After the upper die is located at the bottom dead center,
It is slightly lowered as shown in FIG. Thereby, the warpage of the resin sealing portion (package) can be returned to the original state, and the upper modified bending not affected by the warpage of the package can be performed. Therefore, the bending of the external lead 2 can be performed with high accuracy. Next, the upper die rises with the fixed platen-side pedestal 20 lowered. When the pressing force applied to the semiconductor device 1 is released, the movable platen-side holding member 26 moves the semiconductor device 1 by its own weight.
Can be momentarily held down to prevent the semiconductor device from jumping. Then, the mold is completely opened, and as shown in FIG.
When the suction and transfer device 56 comes over the semiconductor device 1, the fixed platen-side pedestal 20 is raised, and the semiconductor device 1 is suctioned and held by the suction and transfer device 56 and discharged. Thereby, one cycle of the modified bending of the external lead 2 is completed.

The case where the movable plate 16 located above moves vertically is described above. If the fixed plate and the movable plate are relatively movable as described above, the movable plate 16 is moved downward. It is also possible to achieve the same effect even when the mold is opened and closed in the horizontal direction. As described above, various preferred embodiments of the present invention have been described, but the present invention is not limited to these embodiments.
It goes without saying that many more modifications can be made without departing from the spirit of the invention.

[0022]

According to the mold for molding external leads of a semiconductor device according to the present invention, the movable lead moves once in the direction approaching the fixed board, whereby the external leads are once bent toward the fixed board. Then, it is bent toward the movable platen, and the external lead can be suitably modified and bent to a predetermined angle. For this reason, according to the present invention, the external lead can be modified and bent with high precision, the control of the present forming apparatus is simple, and the external lead can be modified and bent efficiently.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a molding apparatus for external lead modification according to the present invention.

FIG. 2 is a sectional view illustrating an operation state of the embodiment of FIG. 1;

FIG. 3 is a sectional view illustrating an operation state of the embodiment of FIG. 1;

FIG. 4 is a sectional view illustrating an operation state of the embodiment of FIG. 1;

FIG. 5 is a cross-sectional view showing another embodiment of a molding apparatus for external lead modification according to the present invention.

FIG. 6 is an explanatory diagram for explaining an operation state of the embodiment of FIG. 5;

FIG. 7 is an explanatory diagram illustrating an operation state of the embodiment in FIG. 5;

FIG. 8 is an explanatory diagram illustrating an operation state of the embodiment in FIG. 5;

FIG. 9 is an explanatory diagram illustrating an operation state of the embodiment of FIG. 5;

FIG. 10 is an explanatory diagram illustrating an operation state of the embodiment in FIG. 5;

FIG. 11 is an explanatory diagram illustrating an operation state of the embodiment in FIG. 5;

FIG. 12 is an explanatory diagram illustrating an operation state of the embodiment in FIG. 5;

FIG. 13 is an explanatory diagram illustrating an operation state of the embodiment in FIG. 5;

FIG. 14 is an explanatory diagram illustrating a conventional technique.

FIG. 15 is an explanatory diagram illustrating a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fixed board 12 Backing plate 14 Die bed 16 Movable board 18 Guide shaft 20 Fixed board side pedestal 22 Cylinder 24 Piston 26 Movable board side holding member 28 Backing plate 30 Presser 32 First spring 34 Washer 36 Gap 38 Stripper 40 Second spring 42 first bending punch 44 first stopper 45 adjustment liner 46 second stopper 48 punch plate 50 second bending punch

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-53387 (JP, A) JP-A-1-218718 (JP, A) JP-A-4-33722 (JP, A) JP-A-3-337 203258 (JP, A) JP-A-1-302755 (JP, A) JP-A-4-57349 (JP, A) JP-A-4-333270 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) H01L 23/50 B21D 3/10

Claims (1)

(57) [Claims] 1. A semiconductor having a fixed board and a movable board capable of reciprocatingly moving in a direction of coming into contact with and separating from the fixed board, and bending and modifying an external lead projecting from a resin sealing portion of the semiconductor device to a predetermined angle. In a molding device for external lead modification of a device, a tip surface for receiving a resin sealing portion of a semiconductor device is provided. In a hole formed in the fixing plate, the tip surface is always kept from the surface of the fixing plate. Projecting, when a pressing force of a predetermined value or more is applied from the movable platen side, a fixed platen-side receiving base elastically supported so as to be movable in the fixed platen direction, and a hole formed in the movable platen side. Normally, when the movable platen is moved in the fixed platen direction, the tip surface protrudes from the surface of the movable platen and is movably supported in opposition to the fixed platen-side pedestal.
A movable platen-side holding member for holding the semiconductor device between the fixed platen-side pedestal and the leading end surface abutting on a resin sealing portion; A stripper supported and provided to be movable toward and away from the movable platen; a semiconductor provided on a side surface of the fixed platen of the stripper and held between the fixed platen-side pedestal and the movable platen-side holding member A first bending punch that abuts against an external lead of the device and bends the external lead toward the fixed board; a first stopper that regulates the stripper and the fixed board so as not to be closer than a predetermined distance; A front end surface that is in contact with the other surface of the resin sealing portion, is provided on the movable plate so as to face the fixed plate side pedestal, the stripper is closest to the fixed plate, and the semiconductor device is a fixed plate side pedestal. While holding it between the Further, when the movable plate is brought close to the fixed plate, a pressing element that abuts on the semiconductor device and presses and moves the semiconductor device and the fixed plate base portion inwardly of the fixed plate to move the fixed plate and the movable plate. A second stopper for restricting the board from coming closer than a predetermined distance; and a second stopper provided on the fixed board, wherein the semiconductor device is held between the presser and the fixed board-side pedestal. A second projecting portion that relatively projects when the table is moved inward of the fixed platen, contacts the external lead, and bends the external lead toward the movable platen;
A die apparatus for modifying external leads of a semiconductor device, comprising: a bending punch.