JPS63142641A - Arm-driving device - Google Patents

Abstract

PURPOSE:To simplify a structure by a method wherein a scrubbing arm is swayed by using a pivotal support to a first guide groove as a fulcrum in such a way that a second guide groove is moved back and forth in the direction of its width while a travelling arm is moved back and forth by using the pivotal support to a side part in one direction of the scrubbing arm as a starting point. CONSTITUTION:When a guide rail 18 is moved back and forth in the upward and downward directions, a scrubbing arm 16 is swayed in the clockwise and counterclockwise directions around a fulcrum 16b1 at its edge part 16b. Through this swaying movement, a travelling arm 6 slides in the left and right directions inside guide grooves 3a and 4a of cross-roller guides 3 and 4 by using a pivotal support (fulcrum 16a1) to a side in one direction of the scrubbing arm 16 as a starting point. A collet 8 is moved back and forth in the left and right directions while it has sucked a semiconductor chip; the bottom part of the semiconductor chip and the mounting part of a lead frame are scrubbed while they are pressed by a prescribed pressure. Through thermal excitation by this scrubbing motion, both metals are diffused at this contact surface; their melting points are lowered to an eutectic temperature; these metals are melted and bonded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an arm driving device suitable for use when bonding a semiconductor chip to a mount portion of a lead frame.

[Conventional technology]

Traditionally, gold-silicon eutectic (A
The u/Si eutectic) mounting method is generally employed.

In other words, when the mounting part of the lead frame is plated with gold and heated at high temperature, and the Si chip is pressed and rubbed (scrubbed) on this gold plating layer, the diffusion of both metals occurs at the contact surface due to thermal excitation. The melting point drops to the eutectic temperature, melting and adhering.

Typically, mounting a semiconductor chip on a lead frame is
This process is carried out continuously every time the lead frame is stopped using an automatic feeding mechanism, and the semiconductor chips are transported one by one, placed with precision on the lead frame mount, and then rubbed. For repeating, a die bonder device is used.

[Problem that the invention seeks to solve]

However, in the conventional die bonder apparatus, a transport mechanism that accurately places the semiconductor chip on the mount part of the lead frame and a scrubbing mechanism that rubs the placed semiconductor chip against the mount part are provided independently. If the mechanism and the scrubbing mechanism were to be constructed integrally, the entire mechanism would become complicated and large.

[Means for solving problems]

The present invention has been made in view of these problems, and includes a first guide groove connected to a swinging arm arranged to be swingable in clockwise and counterclockwise directions about a fixed fulcrum. The groove is caused to move in parallel along a substantially arcuate trajectory by the swinging motion of the swinging arm, and a moving arm is slidably attached to the guide groove, and the moving arm is formed in an abbreviated shape. The scrub arm is pivotally supported at its side surface in one direction, and the vicinity of the proximal end with respect to the side surface in the other direction is pivotally supported in the first guide groove, and the scrub arm is supported in the second guide groove on the other side. By slidingly supporting the second guide groove and moving the second guide groove back in the width direction, the scrub arm is swung about the pivot point with the first guide groove, and the scrub arm is slidably supported in one direction. The movable arm is configured to move back in the sliding direction starting from the pivot point between the movable arm and the movable arm.

[Effect]

Therefore, according to the present invention, the movable arm moves back in the sliding direction in cooperation with the return movement of the second guide groove.

〔Example〕

Hereinafter, the arm drive device according to the present invention will be explained in detail.

FIG. 1 is a schematic front sectional view showing essential parts of an embodiment of this arm driving device, and FIG. 2 is a side sectional view thereof. In the figure, reference numerals 1 and 2 refer to swing arms that are arranged to be able to swing clockwise and counterclockwise about fixed supports 1a and 2a, and 3 and 4 are attached to the free ends of the swing arms 1 and 2. A cross roller guide 5 pivotally supported around movable fulcrums 1b and 2b is installed on the lower end surfaces of the cross roller guides 3 and 4 as shown in the figure, and maintains the parallelism of the guide grooves 3a and 4a of the cross roller guides 3 and 4. 6 is a movable arm slidably attached to the guide grooves 3a and 4a of the cross roller guides 3 and 4 via its roller portion 6a; 7 is a distal end portion (first
A collet body 8 is slidably mounted on the left end (left end in the figure) with a biasing force in the vertical direction in the figure, and a collet 8 is disposed protruding from the lower surface side of the distal end of the collet body 7 with a biasing force in the vertical direction.

The biasing force of the collet 8 in the vertical direction can be adjusted to an appropriate value by a spring pressure adjustment mechanism 9 attached to the upper surface of the collet body 7. A suction port 8a is provided which suctions a semiconductor chip (not shown) by means of a negative pressure acting through the inside of the collet body 7 during the conveying operation and the scrubbing operation. Further, the collet main body 7 has a U-shaped bracket 10 fixed to one side surface on the back side thereof, and a U-shape formed by the joint 10b of the U-shaped bracket 10 with the other side surface 10a. With the space loosely engaged with the upper end surface of the moving arm 6, a compression coil spring (not shown) is interposed between the joint portion 10b and the inside of the moving arm 6, so that the moving arm 6 is attached to the upper end surface of the moving arm 6 in the vertical direction. gaining power. Incidentally, the force exerted by the collet body 7 on the movable arm 6 in the vertical direction can be adjusted using a spring pressure adjustment nut 11.

Further, an abbreviated turnbuckle arm 12 is rotatably attached to the side surface of the distal end of the moving arm 6, and has a one-way surface portion 12b.
A long hole 12b1 is formed in the hole 12b1, and a pin 10c implanted in the other side surface 10a of the U-shaped bracket 10 is loosely fitted into the long hole 12b+. The other direction surface portion 12c side of the turnbuckle arm 12 is connected to the turnbuckle arm 14 via a rod 13, and the turnbuckle arm 14 is rotatably attached to the rear side surface of the movable arm 6 about its fixed fulcrum 14a. It is attached to the section. That is,
A rod 13 is connected to one side of the turnbuckle arm 14, and a roller 14d is rotatably attached to the tip of the other direction side 14c about a fulcrum 14e. When the swing arms 1 and 2 are at the maximum rightward deflection angle position shown in the figure (30'' in the right direction), the lower end of the outer circumferential surface of the roller 14d of the turnbuckle arm 14 is on the right side of the collet body vertical movement contact plate 15. The upper end surface 15a of the protruding piece 15a formed in the upper end surface 15a.

The parts are arranged opposite to each other with a predetermined gap between them. The collet main body vertical movement abutment plate 15 (hereinafter referred to as the abutment plate) is
The collet body is moved up and down by the rotational force of a cam for vertical movement via a worm reduction mechanism (not shown).
The illustrated state shows a state in which it has descended to the lowest position. Further, a protruding piece 15b similar to the protruding piece 15a is formed on the left side of the contact plate 15, and the swing arms 1 and 2 are placed at the maximum leftward deflection angle position ( When the roller 14d of the turnbuckle arm 14 reaches the leftward direction 30' (FIG. 3), the lower end of the outer circumferential surface of the roller 14d of the turnbuckle arm 14 is positioned opposite to the roller 14d with a predetermined gap therebetween.

On the side surface of the movable arm 6 further rearward of the pivot point of the turnbuckle arm 14, there is an abbreviated scrub arm 16 with a fulcrum 16a of its one-way side surface 16a,
This scrub arm 16 is
The L-shaped base end 16b is pivotally supported by the arm par 5 with its fulcrum 16b1 as a pivot. Further, the other end of a compression coil spring 17 whose one end is fixed to the movable arm 6 is hooked to the end of the unidirectional side surface 16 a of the scrub arm 16 . A biasing force acts between the scrub arm 16 and the scrub arm 16. On the other hand, the side surface portion 1 in the other direction of the scrub arm 16
A roller 16d is rotatably attached to the end of the guide rail 6c about a fulcrum 16d1, and this roller 16d is slidably mounted in the guide groove 8a of the guide rail 18. This guide rail 18 is configured to move up and down against the biasing force of compression coil springs 20a and 20b by rocking the scrub cam 19 in the clockwise and counterclockwise directions about the drive shaft 19a. The state indicates that the object is located at the center of its vertical movement range. That is, the outer shape of the scrub cam 19 is in pressure contact with the roller 18b that extends and is supported on the lower side of the guide rail 18.
It has a shape that becomes lower as it rotates clockwise and becomes higher as it rotates counterclockwise. In the illustrated state in which the guide rail 18 is at the center of its vertical movement width, the positional relationship is such that the straight line connecting the fulcrums 16bl and 16d1 of the scrub arm 16 is parallel to the sliding direction of the movable arm 6. .

Next, the operation of the arm drive device configured as described above will be explained. That is, in the state shown in FIG. 1, the movable arm 6 is held in the guide grooves 3a and 4a of the cross roller guides 3 and 4 in a state where it is prevented from sliding in the left-right direction. That is, due to the stationary state of the arm par 5 and the guide rail 18, the scrub arm 1
Since the positions of the fulcrums 16b and 16d of the scrub arm 16 are determined, the position of the fulcrum 16a on the one side surface portion 16a of the scrub arm 16 is also fixedly determined. In other words, since the position of the fulcrum 16a1 of the scrub arm 16 is defined,
The movable arm 6 is held in the guide grooves 3a and 4a of the cross roller guides 3 and 4 in such a manner that it is prevented from sliding. Now, when the swinging arms 1 and 2 are swung counterclockwise around their fixed supports 1a and 2a from this state, the cross roller guides 3 and 4 attached to their free ends will rotate in a circular motion. Moves in an arc-shaped trajectory. That is, since the cross roller guides 3 and 4 are connected by the arm par 5 at their lower end surfaces, they move in parallel while drawing an arcuate trajectory while maintaining the parallelism of the guide grooves 3a and 4a. Along with this, the base end 16b
Scrub arm 16 pivoted to arm par 5 at
The roller 16d attached to the end of the side surface portion 16c in the other direction is guided by the guide groove 18a of the guide rail 18 and moves in an arcuate trajectory. At this time, since the guide rail 18 is located at the center of its vertical movement width and maintains this state, that is, the scrub cam 19 is not yet in the swinging state, the scrub arm 16 is moved by the compression coil spring 1.
It moves while resisting the tensile force of 7. When the swing arms l and 2 reach the maximum leftward swing angle position as shown in FIG. 3, the roller 16d of the scrub arm 16 reaches near the left end of the guide groove 18a of the guide rail 18, and The collet 8 at the tip of the collet 6 is located at a position extending leftward by the amount of movement of the roller 16d compared to the state shown in FIG.

Here, the cross roller guides 3 and 4 of the moving arm 6
The sliding movement in the left-right direction at the fulcrums 16b+ and 16d of the scrub arm 16 is similar to the situation in FIG.
Needless to say, this is prevented by the regulation of the + position. At the maximum leftward deflection angle position of the swing arms 1 and 2, the roller 14d of the turnbuckle arm 14, which is pivotally connected to the rear side surface of the movable arm 6, moves to the contact plate 1.
It is located opposite to the upper end surface 15b1 of the protruding piece 15b of No. 5. At this time, the abutment plate 15 starts to rise due to the operation of the collet main body vertical movement cam, and the upper end surface 15b1 of the protruding piece 15b comes into pressure contact with the roller 14d of the turnbuckle arm 14 and pushes up, moving the turnbuckle arm 14 around the fulcrum 14a. Rotate counterclockwise around the center. This counterclockwise rotation of the turnbuckle arm 14 causes the turnbuckle arm 12 to rotate counterclockwise about the fulcrum 12a through the rod 13, and the pin 10a of the U-shaped bracket 10 through the elongated hole 12bl. is pressed down against the biasing force of the compression coil spring in the moving arm 6. By pressing down the pin 10a, the collet body 7 is lowered relative to the movable arm 6 as shown by the dashed line in the figure. Normally, a semiconductor chip is placed in a precisely positioned position opposite the lowered position of the collet 8 as the collet body 7 is lowered, and the collet 8 is pressed into contact with the upper surface of the semiconductor chip, and the suction port 8a is It is adsorbed by the negative pressure. Thereafter, the contact plate 15 starts to descend to the initial position, and the Gillette main body 7 rises to the original position while holding the semiconductor chip.

From this state, the swing arms 1 and 2 start swinging clockwise, reach the maximum rightward deflection angle position shown in FIG. 1, and stop.

At the maximum rightward swing angle position of the swing arms 1 and 2, the roller 14d of the turnbuckle arm 14 is positioned opposite to the upper end surface 15a1 of the protruding piece 15a of the contact plate 15.

At this time, the contact plate 1 is moved by the operation of the cam for vertically moving the collet body.
5 rises again and uses the turnbuckle arm 14 as the fulcrum 14
The collet body 7 is lowered relative to the moving arm 6 by rotating it counterclockwise around a. Normally, a heated mount portion of a lead frame (not shown) is sequentially automatically sent and placed opposite the lowered position of the collet 8 as the collet body 7 is lowered, and the collet 8 is placed on this mount portion. The bottom surface of the semiconductor chip attracted by the spring pressure adjustment mechanism 9 presses against the biasing force of the spring pressure adjustment mechanism 9. In this way, the operation of transporting the semiconductor chip attracted by the collet 8 is completed.

When the collet 8 presses the semiconductor chip against the mount part, the scrub cam 19 starts to swing clockwise and counterclockwise about its drive shaft 19a, and the scrub cam 19 starts to swing in the clockwise and counterclockwise directions, and moves in the vertical direction of the guide rail 18. The return movement begins. This return movement of the guide rail 18 causes the scrub arm 16 to perform a clockwise and counterclockwise rocking motion about the fulcrum 16b1 at its base end 16b, and this rocking motion causes the movable arm 6 to perform its scrubbing motion. A pivot point (fulcrum 16a,) between the arm 16 and the one-way side surface L6a
Starting from the point, the roller slides in the guide grooves 3a and 4a of the cross roller guides 3 and 4 in the left-right direction. That is, as the moving arm 6 slides in the left-right direction, the collet 8
moves back to the left and right while holding the semiconductor chip, and the bottom of the semiconductor chip and the mounting part of the lead frame are rubbed against each other under a predetermined pressure, and the thermal excitation caused by this scrubbing action causes both surfaces to rub together at the contact surface. Diffusion of the metal occurs, the melting point drops to the eutectic temperature, and the metal is melted and bonded.

After the semiconductor chip is bonded to the lead frame mounting portion, the negative pressure at the suction port 8a of the collet 8 is released, the contact plate 15 is lowered to the initial position, and the collet body 7 is moved against the movable arm 6. After rising, the swinging arms 1 and 2 swing counterclockwise again to pick up the next semiconductor chip, transport it, and repeat the operation of rubbing and adhering it to the mount portion of the lead frame. Note that when the swinging arms 1 and 2 swing clockwise and counterclockwise, the movable arm 6 slightly slides within the guide grooves 3a and 4a of the cross roller guides 3 and 4, but this is not the point at which the semiconductor chip is attracted. At the point where the semiconductor chip is scrubbed, the movable arm 6 is completely prevented from sliding within the guide grooves 3a and 4a, so that its resting position can be obtained with high precision, and the semiconductor chip is can be placed and glued with high precision.

〔Effect of the invention〕

As explained above, according to the arm driving device according to the present invention, the first guide groove is connected to the swing arm arranged to be swingable clockwise and counterclockwise about a fixed fulcrum, and the first guide groove The swinging movement of the swinging arm causes parallel movement while drawing a substantially arc-shaped trajectory, and
A movable arm is slidably attached to this guide groove, and a scrub arm formed in an oval shape is pivotally supported on the movable arm at a side surface in one direction, and the vicinity of the proximal end with the side surface in the other direction is pivoted on the movable arm. The scrub arm is pivotally supported in the first guide groove, and the other side of the scrub arm is slidably supported in the second guide groove, and the second guide groove is moved back in the width direction to move the scrub arm into the second guide groove. Since the movable arm is pivoted using the pivot point with the first guide groove as a fulcrum, and the movable arm is made to move back in the sliding direction using the pivot point with the one direction side surface of the scrub arm as a starting point, the second guide groove The movable arm can be moved back in the sliding direction in cooperation with the backward motion of It becomes possible to provide these functions in an integrated manner, and it becomes possible to simplify the structure of the entire device.

[Brief explanation of the drawing]

FIG. 1 is a schematic front cross-sectional view showing essential parts of an embodiment of an arm drive device according to the present invention, FIG. 2 is a side cross-sectional view of this arm drive device, and FIG. 3 explains the operation of this arm drive device. FIG. 1.2... Swinging arm, la, 2a... Fixed fulcrum,
3.4... Cross roller guide, 3a, 4a... Guide groove, 5... Arm bar, 6... Moving arm, 16
...Scrub arm, 16a...One-way side part, 1
6a+, 16bI... fulcrum, 16b... proximal end, 1
6C...side surface in the other direction, 16d...roller, 18.
...Guide rail, 18a...Guide groove, 19...Scrub cam.

Claims (1)

[Claims] A swinging arm arranged to be able to swing clockwise and counterclockwise around a fixed fulcrum, and connected to the swinging arm and moved in parallel along a substantially arcuate trajectory by the swinging motion of the arm. a first guide groove; a movable arm slidably attached to the guide groove; A substantially L-shaped scrub arm pivotally supported in a guide groove, a second guide groove that slidably supports the other side of the scrub arm, and a second guide groove that moves back in the width direction of the scrub arm. a movable arm return means for swinging the scrub arm using a pivot point with the first guide groove as a fulcrum, and moving the movable arm back in the sliding direction using the pivot point with the one side surface portion as a starting point; Arm drive device.