JP2812606B2 - Press processing device, lead molding method and resin sealing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press device, a lead molding method and a resin sealing method, and more particularly to a device capable of switching a clamping force of a mold for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art FIG. 3 is a front view showing an example of a conventional lead forming apparatus of this kind. In the figure, reference numeral 200 denotes a lead forming apparatus for forming leads of a semiconductor element. The fixed platen 11 on which a lower die 212 for lead forming is mounted, and an upper die 210 for lead forming are opposed to the lower die 212. An upper platen (movable platen) 8 is supported so as to be able to approach and separate therefrom, and a power source 3 for moving the upper platen 8 and the like.

More specifically, the upper mold 210 for lead molding is composed of the movable mold body 1 fixed to the upper platen 8.
0 and the punch 13 attached to the mold 10, and the lower mold 212 for lead molding is composed of a fixed mold main body 12 fixed to the fixed platen 11 and a die 14 attached to the mold 12. It is composed of Here, each mold body 1
At 0 and 12, holding rods 10b and 12b for sandwiching the lead frame 201 are respectively urged in the protruding direction and mounted on both sides of the punch 13 and the die 14. Further, outside these holding rods, the punch 13 is provided. , Die 14
Pin 10 for protecting the shaft from excessive tightening force
a, 12a are attached.

The fixed surface plate 11 is fixed on a frame member 11a assembled on the gantry 1, and a pressing surface plate 2 is horizontally mounted on a middle portion of a side surface of the frame member 11a. Hydraulic device 3 on press platen 2
Is mounted on the frame member 11a, and a crankshaft 4 rotationally driven by the hydraulic device 3 is mounted on the frame member 11a.
Are rotatably supported by the bearing 4a. A plurality of connecting shafts 7 are slidably supported on the fixed surface plate 11. The upper platen 8 is fixed to a tip of the connecting shaft 7 by a fixing nut 9, and is connected to a lower end of the connecting shaft 7. Has a lower platen 6 attached.

A lower end of a connecting rod 5 is swingably supported at the center of the lower platen 6 by a supporting member 5a, and a distal end of the connecting rod 5 is connected to the crankshaft 4. The connection shaft 7 moves up and down via the crankshaft 4 and the connecting rod 5 by driving the hydraulic device 3.

Next, the operation will be described. Fig. 4 (a)-
(d) is an upper mold 210 and a lower mold 212 during lead molding.
FIG. 4A is a view for explaining the movement of the lead mold 200. In the standby state, the lead molding apparatus 200 is in a standby state, and as shown in FIG. Is held at a certain interval from the lower mold 212.

In this state, the lead frame 201 in which the semiconductor element portion is molded with resin is placed on the lower mold 212, and the hydraulic device 3 is driven so that the upper platen 8 is lowered. Shaft 4
Rotates, and the movement is transmitted to the lower platen 6 via the connecting rod 5 as vertical movement. At this time, since the connecting shaft 7 connected to the lower platen 6 and the upper platen 8 are integrated by the fixing nut 9, the vertical movement of the lower platen 6 is the same as the vertical movement of the upper platen 8 via the connecting shaft 7. Become. As a result, the upper mold 210 and the lower mold 212 come close to each other, and the holding rods 10 b, 12 protruding from the mold bodies 10, 12.
b presses and holds the lead frame 201 (FIG. 4)
(b)).

When the upper platen 8 is continuously lowered, the upper and lower pressing rods 10b and 12b are immersed in the mold main bodies 10 and 12 while the lead frame 201 is held therebetween, and the upper mold 13 comes into contact with the lead frame 201 on the lower die 14 (see FIG. 4C). When the upper platen 8 is further lowered for a predetermined distance and stopped, the punch 13 and the die 14 press the lead frame 201, that is, separate the semiconductor element (not shown) from the lead frame 201 and remove the lead of the semiconductor element. The molding is performed simultaneously (see FIG. 4 (d)).

[0009]

However, in the conventional lead forming apparatus, the upper and lower dies 21 are operated by the hydraulic device 3.
Since a so-called hydraulic drive system for tightening the nuts 0 and 212 is used, maintenance such as inspection and prevention of oil leakage and replacement of a seal member of a hydraulic device is very complicated, and the clamping force is controlled with high precision. And the responsiveness is poor.

That is, since the platen 8 is raised and lowered by the rotation of the crankshaft 4, the stop position of the platen 8 at the time of mold clamping varies, causing an error in the mold clamping force. If the stroke of the platen 8 has a margin at the time of mold clamping, even if lead molding is incomplete, the upper platen 8 can be used.
Can be further lowered to correct the lead. However, in the above-described conventional apparatus, the up-and-down stroke of the platen 8 is restricted by the shape of the crankshaft 4, so there is no margin, and high-quality products can be manufactured with high productivity. In addition, the time required to move the mold to a predetermined height position is also a problem in mass production, and the responsiveness of mold clamping is not good.

If the number of leads of the semiconductor device to be molded is different, the clamping load of the molding die also varies, but only one power source for generating the clamping force as in the conventional device is used.
However, in order to change the mold clamping force, it is necessary to adjust the hydraulic pressure of the hydraulic device, and it is not possible to retighten according to the molding condition of the lead. There was a point.

By the way, Japanese Patent Application Laid-Open Nos. 62-28220 and 2-45111 disclose a mold clamping device that performs mold clamping by using two driving sources. The mold is opened and closed by a drive source, and the mold is clamped by the other drive source. A hydraulic drive type is also used as the drive source, which has the same problems as the above-mentioned conventional device. is there.

[0013] The present invention has been made in view of the above problems, is easy to maintain, and can control the mold clamping force without adjusting the press driving source according to the press working situation, and can provide high quality. It is an object of the present invention to obtain a press device capable of performing high-precision press working.

According to the present invention, a lead of a semiconductor device can be formed with high precision and high productivity by appropriately controlling the clamping force of a lead forming die, and a lead capable of forming a high quality lead can be obtained. It is an object to provide a molding method.

Another object of the present invention is to provide a resin sealing method capable of performing resin sealing of a semiconductor device with good productivity by appropriately controlling a mold clamping force of a resin sealing mold. .

[0016]

According to the present invention, there is provided a press working apparatus comprising: a fixed platen for holding a fixed mold member; and a movable mold member facing the fixed mold member and capable of approaching and separating from the fixed mold member. A movable platen for supporting the movable platen, a main power source for moving the movable platen, and an auxiliary power source attached to the movable platen; consists of a connecting rod that connects the source and the movable mold member, provided with an auxiliary pressing mechanism for pressing the movable mold member to the fixed die member is displaced relative to the movable platen by the auxiliary power source, the main power
The movable mold member is pressed against the fixed mold member by the
Auxiliary press machine according to the pressing force required by the work station
The press force is applied by the structure .

According to the present invention, there is provided the above press working apparatus,
A second auxiliary power source is provided on the fixed surface plate, and the fixed mold member is supported so as to be able to protrude and retract from the support surface plate, and the fixed mold member is connected to the second auxiliary power source by a connecting rod. And a second auxiliary press mechanism for pressing the fixed mold member against the movable mold member.

According to the present invention, in the above press working apparatus,
As the main power source, there is provided a main power device including a motor that generates a clamping force of the two mold members by rotating a threaded shaft, and a motor control unit that controls a torque of the motor. A power source is provided with an auxiliary power device including an auxiliary motor that generates a clamping force of the two mold members by rotating a shaft with a screw, and auxiliary motor control means that controls the torque of the motor. .

A lead forming method according to the present invention is a method of forming leads of a semiconductor element by using the above-mentioned press working apparatus, wherein a die is provided in a fixed mold body as the fixed mold member, and the movable mold is provided. The movable platen is driven by a pair of upper and lower lead forming dies for separating the semiconductor element from the lead frame and forming the leads of the semiconductor element at the same time by incorporating a punch into the movable mold body as a mold member. The upper and lower lead molding dies are clamped so that a predetermined clamping force is generated between them, and in this state, the punch is moved by the auxiliary driving source to separate the semiconductor element and to separate the leads. This is for molding.

A resin sealing method according to the present invention is a method of sealing a semiconductor element with a resin using the above-mentioned press working apparatus, wherein a lead frame is sandwiched between the fixed and movable mold members. In this state, using a pair of upper and lower resin sealing dies in which a resin filling space is formed so as to surround the element mounting portion of the lead frame, the movable platen is moved by a main power source, and the both dies are predetermined tightening force is tightened type as those generated during, in this state, the movable-side resin sealing mold to move by an auxiliary driving source, type as the clamping force is generated added between the dies This is for tightening.

[0021]

In the present invention, an auxiliary power source is mounted on a movable platen, and a movable mold member of a lead molding die mounted on the movable platen is connected to the auxiliary power source by a connecting rod. Since the auxiliary press mechanism for displacing the movable mold member with respect to the movable platen and pressing the movable mold member against the fixed mold member is provided, the movable platen is moved by the main power source to clamp the pair of lead forming dies. After this, the movable power member can be pressed against the fixed metal member by the auxiliary power source, and the mold can be retightened without adjusting the press drive source according to the processing situation. High quality and high precision press working can be performed.

Further, in the present invention, a second auxiliary power source is disposed on the fixed base, and the fixed mold member is supported so as to be able to protrude and retract from the fixed base, and the fixed mold member is connected. Since the second auxiliary power source is connected to the second auxiliary power source by a rod and presses the fixed mold member against the movable mold member, the retightening of the mold can be performed in multiple stages by switching. it can.

In the present invention, the main power source includes a main motor for generating a clamping force of the two lead molding dies, and a main motor control means for controlling the torque of the motor. As an auxiliary power source, an auxiliary power device including an auxiliary motor for generating a mold clamping force between the fixed and movable mold members and auxiliary motor control means for controlling the torque of the motor was used. Fine control of the tightening force is possible, and the quality can be further improved. Further, since a hydraulic mechanism is not used in the drive system, maintenance is easy.

Further, in the present invention, a die and a punch are respectively incorporated in a pair of lead forming dies by using the above-mentioned press working apparatus for forming leads of a semiconductor element.
Since the movable platen is moved by the main power source, the lead molding die is clamped so that a predetermined clamping force is generated therebetween, and in this state, the punch is moved by the auxiliary drive source. In addition, the molding of the leads of the semiconductor device can be performed with high accuracy and high productivity by appropriately controlling the mold clamping force of the lead molding die, and high quality lead molding can be performed.

Still further, in the present invention, the press working apparatus is used for resin sealing of the semiconductor element, and the lead frame is sandwiched between the fixed mold and the movable mold member as the fixed mold and the movable mold member. Using a pair of upper and lower resin sealing dies in which a resin filling space is formed so as to surround the element mounting portion, the movable platen is moved by a main power source, and the two dies are fixed to each other by a predetermined tightening force. There tighten type to occur, in this state, the movable-side resin sealing <br/> mold by moving the auxiliary driving source, performing mold clamping as the clamping force is generated added between the dies Thus, the resin sealing of the semiconductor device can be performed with good productivity by appropriately controlling the mold clamping force of the resin sealing mold.

[0026]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a front view showing the overall configuration of a lead forming apparatus according to an embodiment of the present invention. In the figure, reference numeral 100 denotes a lead forming apparatus according to the present embodiment. The punch 13 is moved upward and downward by using the upper die body 10 for lead molding.
The punch 13 is independently raised and lowered by an auxiliary motor (auxiliary power source) 25 arranged on the upper surface of the upper platen 8.

That is, the ball screw 20 is threadedly engaged with a nut member 21 mounted on a central portion of the lower platen 6 and provided through the lower platen 6.
Its lower end is supported by a bearing 22 attached to the gantry 1 and its upper end is connected to the fixed surface plate 11 as a main power source.
Is connected to a rotating shaft 19 of a motor 18 attached to the lower surface of the motor.

The punch 13 is supported so as to be able to protrude and retract within an upper mold body 10 attached to the lower surface of the upper platen 8, and together with the upper mold body 10, an upper mold 11 for lead molding.
0, and the punch 13
Is connected to a punch pressing ball screw 26 which rotates and advances / retreats due to the rotation of. Further, a lower mold body 12 is attached to the fixed surface plate 11, and inside the lower mold body 12,
A die 14 is embedded so as to face the punch 13 and form a pair. The die 14 together with the lower die body 12 constitute a lower die 112 for lead molding. The upper and lower dies 110 and 112 for forming the leads are provided with the holding rods 10b and 12 urged in the protruding direction, similarly to the conventional device.
b and stopper pin 1 for protecting punch 13 and die 14
0a and 12a are attached. At four corners on the lower surface of the gantry 1, adjust members 1a for adjusting the height position of the work in accordance with the height of the worker are attached.

Next, the operation will be described. Fig. 2 (a)-
FIG. 2D is a view for explaining the operation of the lead forming apparatus 100. In a standby state, the lead forming apparatus 100 has a pair of upper and lower leads for forming a lead as shown in FIG. The dies 110 and 112 are held at regular intervals.

When forming the leads, the lead frame 201 in which the semiconductor element portion is resin-molded is placed on the lower mold 112, and when the main power motor 18 is driven in the mold clamping direction, the ball screw 20 rotates. As a result, the lower platen 6 is pushed down, whereby the upper mold 110 for lead molding descends onto the lower mold 112 for lead molding.

When the upper mold 110 descends a predetermined distance,
The holding rod 10b of the upper mold 110 is connected to the lead frame 20.
1 and is sandwiched together with the lower mold pressing rod 12b (see FIG. 2 (b)). When the upper mold 110 further descends by a certain distance, the punch 13 of the upper mold 110 comes into contact with the lead frame 201 on the die 14 of the lower mold 112 , and a clamping force is generated between the punch 13 and the die 14. When the mold clamping force reaches a value corresponding to the maximum torque of the main power motor 18, the rotation of the ball screw 20 stops (see FIG. 2C).

In the state where the first-stage mold clamping by the main power motor 18 is completed, the ball screw 26 is rotated by the auxiliary power motor 25 as necessary to
3 is pressed toward the die 14 to perform additional tightening to perform the second-stage mold clamping. Accordingly, it is possible to cope with a case in which the molding state of the lead is insufficient in the mold clamping state in the first stage, and a lead molding die having a mold clamping load larger than that of the standard type.

As described above, in this embodiment, the auxiliary power motor 25 is attached to the upper platen 8 and the punch 1 is removably inserted into the upper mold 110 fixed to the upper platen 8.
3 and the punch 13 is attached to the auxiliary power motor 25.
Since to press the punch pressing the ball screw 26 is rotated, the lead formed by the main power motor 18, in a state where the lower mold 110, 112 is Me clamping, optionally assisted by The power motor 25 presses the punch 13 against the die 14 to perform additional mold clamping. Even if a mold having a different mold clamping load is mounted, the second stage mold can be adjusted without adjusting the power source for mold clamping. High quality and high precision products can be manufactured by controlling the tightening force. Further, in the apparatus of this embodiment, since the motor is used as the power source, there is an effect that maintenance is easier than in the hydraulic drive system.

In the above embodiment, the punch 13 of the upper mold 110 is driven by the auxiliary power motor 25 independently of the upper platen 8 to generate an additional tightening force. As for the die, the platen 8
May be configured to generate a mold clamping force that is independent of the clamping force of the mold.

Hereinafter, a lead forming apparatus having such a configuration will be described with reference to FIG. 1 as a second embodiment. A second auxiliary motor (not shown) is provided on the fixed surface plate 11 as an auxiliary power source. The die 14 is supported by the lower mold body 12 so as to be able to protrude and retract from the lower mold 112, and the die 14 is connected to a second auxiliary motor by a connecting rod (not shown). To the punch 13 side. In this case, there is an effect that the tightening of the upper and lower lead molding dies can be switched in multiple stages.

In each of the above embodiments, the power source is
Although a motor that simply generates a rotational force is used, it controls the torque of the motor in addition to the motor that generates the clamping force of the two dies by rotating the ball screw 20 as the main power source. A motor control means is provided, and as each of the auxiliary power sources, the ball screw 26 is rotated to rotate the punch 1
Auxiliary motor 2 that generates a mold clamping force between die 3 and die 14
In addition to the above, an auxiliary motor control means for controlling the torque of the motor may be provided. In this case, fine control of the mold clamping force becomes possible, and the quality can be further improved.

Further, in the above description, the lead molding device of the semiconductor device has been described. However, the press mechanism employed in the lead molding device may be used in a device for sealing a semiconductor element with resin.

Hereinafter, a resin sealing device according to a third embodiment of the present invention will be briefly described with reference to FIG. 1. In place of the die 14 and the punch 13 of the device 100 shown in FIG. With the frame sandwiched, using a pair of upper and lower resin sealing dies in which a resin filling space is formed so as to surround the element mounting portion of the lead frame, the movable platen is moved by a main power source, and mold was clamped type as predetermined clamping force between them occurs, in this state, the movable-side resin sealing mold to move by an auxiliary driving source, additional clamping force between the molds occurs Mold clamping may be performed. In this case, there is an effect that the resin sealing of the semiconductor device can be performed with good productivity by appropriately controlling the mold clamping force of the resin sealing mold.

Further, in the above description, the power transmission system in the press mechanism is shown by a direct drive system of a ball screw . However, the power transmission system is not limited to this, and for example, a system using a crankshaft in a conventional device is used. Can also be adopted.

[0040]

As described above, according to the press working apparatus according to the present invention, the auxiliary power source is mounted on the movable platen, and the movable die member of the lead molding die mounted on the movable platen is connected to the auxiliary power source by the connecting rod. An auxiliary press mechanism is connected to the power source and displaces the movable mold member with respect to the movable platen by the auxiliary power source and presses the movable mold member against the fixed mold member. Even after the pair of lead molding dies is clamped, the movable power member can be pressed against the fixed mold member by the auxiliary power source. The mold can be retightened without adjustment, and there is an effect that high-quality and high-precision press working can be performed.

According to the present invention, in the press working apparatus, a second auxiliary power source is provided on the fixed base, and the fixed mold member is supported so as to be able to protrude and retract from the fixed base. Since the fixed die member is connected to the second auxiliary power source by a connecting rod and the second auxiliary press mechanism for pressing the fixed die member against the movable die member is provided, the retightening of the die is frequently performed. There is an effect that the switching can be performed in stages.

Further, according to the present invention, in the above-mentioned press working apparatus, as each of the power sources, a power source comprising a motor for generating a clamping force of the two dies and a motor control means for controlling the torque of the motor. Since the apparatus is used, fine control of the mold clamping force can be performed, and the quality can be further improved. Further, since the driving system is not a hydraulic mechanism but a motor, there is an effect that maintenance is easy.

Further, according to the lead forming method of the present invention, a die and a punch are incorporated into a pair of lead forming dies by using the above-mentioned press working apparatus for forming leads of a semiconductor element, and the movable platen is mainly used. The punch is moved by a power source to clamp the lead molding die so that a predetermined clamping force is generated therebetween. In this state, the punch is moved by an auxiliary driving source. Can be performed with high accuracy and high productivity by appropriately controlling the mold clamping force of the lead molding die, and there is an effect that high quality lead molding can be performed.

Further, according to the resin sealing device of the present invention, the above-mentioned press working device is used for resin sealing of the semiconductor element, and a lead frame is held between the fixed die and the movable die member therebetween. In this state, using a pair of upper and lower resin sealing dies in which a resin filling space is formed so as to surround the element mounting portion of the lead frame, the movable platen is moved by a main power source, and the both dies are predetermined tightening force is tightened type as those generated during, in this state, by moving the auxiliary driving source the movable side resin sealing mold,
Since the mold clamping is performed so that an additional clamping force is generated between the two molds, the resin sealing of the semiconductor device can be performed with good productivity by appropriately controlling the mold clamping force of the resin sealing mold. Has the effect of being able to

[Brief description of the drawings]

FIG. 1 is a front view showing the overall configuration of a lead forming apparatus according to an embodiment of the present invention.

FIG. 2 is a view for explaining the operation of the lead forming apparatus.

FIG. 3 is an overall front view showing an example of this type of conventional lead forming apparatus.

FIG. 4 is a diagram for explaining the operation of the conventional device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Stand 6 Lower platen 7 Connecting shaft 8 Upper platen 9 Fixed nut 10 Upper mold main body 10a, 12a Stopper pin 10b, 12b Holding rod 11 Fixed surface plate 12 Lower mold main body 13 Punch (movable mold member) 14 Die (Fixed) Mold member) 18 Main power motor (Main power source) 19 Drive shaft 20 Ball screw 21 Nut 22 Bearing 25 Auxiliary power motor (Auxiliary power source) 26 Ball screw for pressing punch 100 Lead forming device 110 Upper die for lead forming 112 Lower mold for lead molding

Continued on the front page (51) Int.Cl. ⁶ Identification code FI B30B 15/14 B30B 15/14 K H01L 21/56 H01L 21/56 T // B29L 31:34

Claims (5)

(57) [Claims] 1. A fixed platen for holding a fixed mold member, a movable platen for supporting a movable mold member facing the fixed mold member so as to be able to approach and separate from the fixed mold member, and a main body for moving the movable platen A press working apparatus comprising a power source and press-working a work between the two dies, comprising: an auxiliary power source attached to the movable platen; and a connection connecting the auxiliary power source and the movable mold member. An auxiliary press mechanism for displacing the movable mold member with respect to the movable platen by the auxiliary power source and pressing the movable mold member against the fixed mold member, wherein the movable power member is fixed to the fixed mold member by the main power source. Pressed on
The above-mentioned supplementary work depends on the pressing force required by the work.
A press working device wherein a press force is applied by an auxiliary press mechanism . 2. The press working apparatus according to claim 1, wherein a second auxiliary power source is disposed on the fixed base, and the fixed mold member is supported so as to be able to protrude and retract from the fixed base. A press working apparatus comprising a second auxiliary press mechanism configured to connect a fixed mold member to a second auxiliary power source by a connecting rod and to press the fixed mold member toward the movable mold member. 3. The press working apparatus according to claim 1, wherein the main power source is a motor that rotates a shaft with a screw to generate a mold clamping force of the two mold members, and a torque of the motor is generated. A main power unit comprising: a motor control means for controlling the motor; and an auxiliary motor for generating a clamping force for the two mold members by rotating a threaded shaft as the auxiliary power source, and controlling a torque of the motor. A press working device comprising an auxiliary power device comprising: 4. A method for forming a lead of a semiconductor element using the press working apparatus according to claim 1, wherein a die is provided in a fixed mold body as the fixed mold member, and a movable mold member is provided as the movable mold member. Using a pair of upper and lower lead molding dies for forming a semiconductor element lead at the same time as separating the semiconductor element from the lead frame, in which the punch is incorporated in the movable mold body, moving the movable platen by the main power source Then, the upper and lower lead forming dies are clamped so that a predetermined tightening force is generated therebetween, and in this state, the punch is moved by an auxiliary driving source to separate the semiconductor element and form the leads. A lead forming method characterized by the above-mentioned. 5. A method for performing resin sealing of a semiconductor element using the press working apparatus according to claim 1, wherein a lead frame is held between the fixed and movable mold members. Using a pair of upper and lower resin sealing dies in which a resin filling space is formed so as to surround the element mounting portion of the lead frame, the movable platen is moved by a main power source, and the two dies are fixed between them. and the clamping die as clamping force is generated, in this state, the movable-side resin sealing mold to move by an auxiliary driving source, by performing mold clamping so that additional clamping force between said molds is produced A resin sealing method.