JPH09307048A - Method and apparatus for bending lead of semiconductor package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bending apparatus for a lead of a semiconductor package, which can precisely bend the lead while suppressing spring back as much as possible, and preventing occurrence of a crack or gap around the base of the lead, whereby improves quality, yield and reliability of products. SOLUTION: The bending apparatus press-holds a rear end 3a of a lead 3 of a semiconductor package 1, presses an intermediate portion 3c of the lead 3 somewhat away from the rear end 3a with a first curving roller 17, to a middle curved position, and presses around a bending start point 3b near the rear end 3a rather than the intermediate portion 3c with a second bending roller 18, to a desired curved angle position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor package lead bending method and device for bending a metal lead portion (terminal portion) of a semiconductor package so as to be directed obliquely downward with respect to a main body portion.

[0002]

2. Description of the Related Art A conventional example of this type of lead bending apparatus is shown in FIG.
Shown in This lead bending device 50 sandwiches a rear end portion 3a of a required lead portion 3 which is straightly projected laterally (horizontally) from a resin main body portion 2 of a semiconductor package 1 (semi-finished product) schematically shown. A fixed die 52 for holding pressure and a holding portion 54 that is movable in the vertical direction with respect to the die 52, and is slidably attached to the holding portion 54 and is movable in the same direction as the movable holding portion 54. The roller holding portion 56 to be urged, the bending roller 58 rotatably held at the tip of the roller holding portion 56, the stepped pusher 60 for pushing down the pressing portion 54 and the roller holding portion 56, and the illustration are shown. Although not provided, a return mechanism for moving or urging the pressing portion 54 and the roller holding portion 56 to a standby position above the semiconductor package 1 is provided. That.

Lead bending by such a device 50 is
First, the rear end portion 3a of the lead portion 3 of the semiconductor package 1 is positioned between the convex portion 52a of the die 52 and the convex portion 54a of the pressing portion 54, and the pusher 60 is rapidly lowered. Then, the roller holding member 56 and the pressing portion 54 are pushed downward, and as shown in FIG. 4 (A), the rear end portion 3a of the lead portion 3 has the convex portion 52a of the die 52 and the pressing portion 54.
The bending roller 58 presses the vicinity of the bending start point portion 3b, which is slightly closer to the tip end, from the rear end portion 3a of the lead portion 3, and the lead portion 3 that is straight is bent by the bending roller 58. It begins to be bent by 58.

Further, the roller holding member 56 is further pushed down by the pusher 60, as shown in FIG.
As shown in (B), the lead portion 3 has a bending roller 58.
The pressing force of B bends until the desired bending angle is obtained.

[0005]

In the conventional lead bending method and apparatus as described above, the lead portion 3 is bent at a stretch by pressing the bending portion 58 near the rear end portion 3a and the bending start portion 3b. Moreover, in order to prevent the desired bending angle from being obtained in the lead portion 3 due to springback (a phenomenon in which the bent lead portion returns slightly to the original direction due to its elasticity), the lead portion 3 is actually required. The bending angle is larger than the required bending angle.

Therefore, not only the bending accuracy of the lead portion is poor, but the semiconductor package 1 in which lead bending is performed by the conventional device 50 is shown in FIG. 5 (A) as a whole, and in FIG. 5 (B) as a root portion of the lead portion. As shown in the enlarged view, the resin main body 2
A crack C is likely to occur in the vicinity of the root of the lead portion 3 at.

Further, the holding portion 54 and the holding portion 54
It is not a separate body from the roller holding part 56 slidably attached to the holding part 54, and the pressing part 54 and the roller holding part 56
Since there is only one pusher 60 for pushing down and, the lead is not sufficiently pressed by the pressing portion 54 in the bending process, and the rattling or the gap S is likely to occur.

Since the crack C and the gap S deteriorate the product quality such as moisture resistance, they have to be eliminated as defective products, and there is a problem that the yield decreases.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to make it possible to bend a lead portion with high accuracy while preventing springback as much as possible, and to lead the lead portion. It is an object of the present invention to provide a method and an apparatus for bending a lead of a semiconductor package, in which cracks and gaps are less likely to occur near the root of the semiconductor package, and thus product quality, yield, and reliability can be improved.

[0010]

In order to achieve the above-mentioned object, a method of bending a lead of a semiconductor package according to the present invention is to hold the rear end portion of the lead portion of the semiconductor package by pinching and hold the rear portion of the lead portion. After bending the middle part, which is slightly away from the end part, with the first bending roller to bend it halfway,
It is characterized in that the vicinity of the bending start point portion closer to the rear end portion than the middle portion of the lead portion is pressed by the second roller to bend until a desired bending angle is obtained.

In the lead bending apparatus according to the present invention, the die and the movable pressing portion for holding and holding the rear end portion of the lead portion of the semiconductor package, and the movable pressing portion are independently moved in the same direction. And a roller holding portion that is separated from the roller holding portion by a predetermined distance in the moving direction of the roller holding, and is also separated from each other by a predetermined distance in a direction orthogonal to the moving direction. A first bending roller and a second bending roller held,
The rear end of the lead portion of the semiconductor package is clamped and held by the die and the movable pressing portion, and the holding portion is moved to the lead portion side, so that the lead portion of the lead portion is slightly moved from the rear end portion. After pressing the distant intermediate portion with the first bending roller to bend it halfway, the vicinity of the starting point of the lead portion closer to the rear end portion than the intermediate portion of the lead portion is pressed with the second roller to obtain a desired shape. Bending until the bending angle of is obtained.

In the lead bending method and apparatus of the present invention configured as described above, the lead portion is pressed stepwise by the two bending rollers, and the portion apart from the rear end portion is pressed first. Since the spring back is suppressed as much as possible, there is no need to bend it excessively considering the spring back unlike the conventional one, and the load of the lead part especially at the root part is compared to the conventional one. This significantly reduces the cracks and gaps near the roots of the lead portions, and bends the lead portions with high accuracy, resulting in improved product quality, yield, and reliability.

In the lead bending apparatus of the present invention, the first bending roller and the second bending roller are arranged on a common roller holding member with a predetermined separation distance so that the two bending rollers are moved simultaneously. When configured, the mechanism and its control are simpler and easier than those in which two bending rollers are individually moved at a predetermined timing, which is advantageous in terms of device cost and bending accuracy. It is also excellent (the mechanism is complicated to move the two bending rollers individually, and it is difficult to adjust their timing).

Further, in the lead bending apparatus of the present invention, since the movable pressing portion and the roller holding portion are separate bodies so that they can be moved independently of each other, the lead and the movable pressing portion maintain a constant pressure on the lead portion. Since it is possible to hold the clamping pressure, it is possible to prevent cracks and gaps from being generated near the root of the lead portion, and the lead portion can be bent with high accuracy, resulting in further improvement in product quality, yield, and reliability.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a lead bending apparatus to which the lead bending method according to the present invention is applied. The lead bending apparatus 10 sandwiches a rear end portion 3a of a required lead portion 3 which is straightly projected laterally (horizontal direction) from a resin main body portion 2 of a semiconductor package 1 (semi-finished product) shown schematically. A fixed die 12 for holding pressure and a holding portion 14 movable in a vertical direction with respect to the die 12.
A roller holding portion 16 which is independently movable in the same direction as the movable holding portion 14, and a first bending roller 17 and a second bending roller 17 which are held by the roller holding portion 16 in a predetermined manner as described later. The bending roller 18, the two pushers 21 and 22 for individually pushing down the pressing portion 14 and the roller holding portion 16, and the pressing portion 14 and the roller holding portion 16 (not shown) are provided in the semiconductor package. 1, a return mechanism for moving or urging to a standby position above 1.

The first bending roller 17 and the second bending roller 18 are separated from each other in the roller holding portion 16 by a predetermined distance α along the moving direction (vertical direction) of the roller holding 16. It is rotatably held in a state in which it is urged and separated from each other by a predetermined distance β in the direction orthogonal to the moving direction.

In the lead bending by the device 10 of the present embodiment having such a configuration, first, the rear end portion 3a of the lead portion 3 of the semiconductor package 1 is formed into the convex portion 12a of the die 12 and the convex portion 14a of the pressing portion 14. And pusher 2
Lower 1 As a result, the pressing portion 14 is pushed downward, and as shown in FIG. 2A, the rear end portion 3a of the lead portion 3 is formed by the convex portion 12a of the die 12 and the convex portion 14a of the pressing portion 14. Clamping pressure is maintained.

Then, the pusher 22 is lowered to push the roller holding portion 16 downward. Then, Figure 2
As shown in (B), the first bending roller 17 presses the intermediate portion 3c of the lead portion 3 which is slightly separated from the rear end portion 3a. As a result, the straight lead portion 3 of the required book begins to bend from the beginning point 3b of the bend near the rear end 3a.

Then, when the roller holding portion 16 is further lowered, this time, as shown in FIG. 2C,
A second roller 18 presses the vicinity of a bending start point portion 3b closer to the rear end portion 3a than the intermediate portion 3c in the lead portion 3 which is bent halfway by the first bending roller 17,
Thereby, it is bent until the desired bending angle is obtained.

As described above, in this embodiment, the lead portion 3 is pressed stepwise by the two bending rollers 17 and 18, and the portion (3c) apart from the rear end portion 3a is pressed first. Since the spring back is suppressed as much as possible, it is not necessary to bend the spring back excessively considering the spring back unlike the conventional one, and the load of the lead part 3, especially the root part is less than the conventional one. As a result, cracks and gaps are less likely to occur near the roots of the lead portions 3 and the lead portions 3 can be bent with high precision, resulting in improved product quality, yield, and reliability.

The lead bending apparatus 10 of the present invention is the first
When the first bending roller 17 and the second bending roller 18 are arranged on the common roller holding member 16 with a predetermined separation distance (α, β), and the two bending rollers 17 and 18 are simultaneously moved, The mechanism and its control are simpler and easier than the one in which two bending rollers are individually moved at a predetermined timing, which is advantageous in terms of apparatus cost and excellent in bending accuracy. Will be things.

The configuration of each part of the apparatus 10 described above is as follows.
It is needless to say that the arrangement of the bending rollers 17 and 18, the shapes of the die 12 and the pressing portion 14 and the like can be appropriately changed according to the size and shape of the semiconductor package and its lead portion.

[0024]

As can be understood from the above description, according to the lead bending method and device for a semiconductor package of the present invention, the lead portion is stepwise by two bending rollers and from the rear end portion. Since the distant part is pressed first, the springback can be suppressed as much as possible, and it is not necessary to bend it excessively considering the springback unlike the conventional one, and especially the root of the lead part. It is possible to significantly reduce the load on the part compared to the conventional one, it is possible to prevent cracks and gaps from occurring near the root of the lead part, and it is possible to bend the lead part with high accuracy.
As a result, product quality, yield, and reliability can be improved.

In the lead bending apparatus of the present invention, the first bending roller and the second bending roller are arranged on a common roller holding member with a predetermined separation distance so that the two bending rollers are moved simultaneously. When configured, the mechanism and its control are simpler and easier than those in which two bending rollers are individually moved at a predetermined timing, which is advantageous in terms of device cost and bending accuracy. The effect of being excellent is also obtained.

Further, in the lead bending apparatus of the present invention, the movable pressing portion and the roller holding portion are separate members so that they can be moved independently, so that the lead portion is kept at a constant pressure by the die and the movable pressing portion. Since it is possible to hold the clamping pressure, it is possible to prevent cracks and gaps from being generated near the root of the lead portion, and the lead portion can be bent with high accuracy, resulting in further improvement in product quality, yield, and reliability.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an overall configuration of a semiconductor package lead bending apparatus to which a method according to the present invention is applied.

FIG. 2 is a diagram provided for explaining a lead bending operation / process by the lead bending apparatus shown in FIG.

FIG. 3 is a diagram which is used for describing a lead bending method and a device configuration of a conventional semiconductor package.

FIG. 4 is a diagram provided for explaining a lead bending operation / process by the lead bending apparatus shown in FIG.

5A and 5B are diagrams provided for explaining a problem caused by a conventional lead bending method and apparatus, in which FIG. 5A is a completed semiconductor package product, and FIG. 5B is a partially enlarged view of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 semiconductor package 3 lead part 3a rear end part 3b bending start point part 3c middle part 10 lead bending device 12 die 14 holding part 16 roller holding part 17 first bending roller 18 second bending roller 21, 22 pusher

Claims (3)

[Claims] 1. A method of holding a rear end portion of a lead portion of a semiconductor package under pressure, and pressing a middle portion of the lead portion, which is slightly away from the rear end portion, with a first bending roller to bend the lead portion halfway. A method for bending a lead of a semiconductor package, comprising: pressing a portion near a bending start point closer to the rear end portion than the middle portion of the lead portion with a second roller to bend the lead portion until a desired bending angle is obtained. 2. A die and a movable holding portion for holding and holding a rear end portion of a lead portion of a semiconductor package, a roller holding portion which is independently movable in the same direction as the movable holding portion, and a roller holding portion. A first bending roller that is held in the portion by a predetermined distance from each other along the moving direction of the roller holding and is also held by a predetermined distance from each other in a direction orthogonal to the moving direction; Second
The bending roller is provided, and the rear end of the lead portion of the semiconductor package is clamped and held by the die and the movable pressing portion, and the holding portion is moved to the lead portion side, The intermediate portion, which is slightly away from the rear end portion, is pressed by the first bending roller to bend it halfway, and then the second roller is provided in the vicinity of the start point portion of the lead portion, which is closer to the rear end portion than the intermediate portion. A lead bending apparatus for a semiconductor package, wherein the lead bending apparatus is adapted to be pressed until it is bent until a desired bending angle is obtained. 3. The lead bending apparatus for a semiconductor package according to claim 2, wherein the movable pressing portion and the roller holding portion are separate bodies so as to be independently movable.