JP3376876B2 - Apparatus and method for transferring conductive balls - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive ball transfer device and method for transferring conductive balls onto a work.

[0002]

2. Description of the Related Art Flip chips and BGA (Ball G)
A method using conductive balls such as solder balls is known as a method of manufacturing an electronic component with bumps such as a grid array. Further, as a method of transferring the conductive balls to a work such as a chip or a substrate, a method using a suction head has been implemented.

According to this method, conductive balls stored in a container or the like are vacuum-sucked and picked up in a large number of suction holes formed on the lower surface of the suction head, and the suction head is moved above the work to conduct these conductive balls. Since the conductive balls are transferred onto the electrodes of the work and a large number of conductive balls can be transferred onto the work all at once, there is an advantage that workability is good.

[0004]

However, in the method of transferring the conductive balls to the work by using the suction head, a pickup error as described below tends to occur when the conductive balls are vacuum-sucked. . That is, when the conductive balls are vacuum-sucked by the suction head, the suction head is lowered into the supply portion of the conductive balls accumulated by stacking a large number of conductive balls. However, one conductive ball is not always vacuum-adsorbed.

For example, when a plurality of conductive balls are vacuum-sucked in one suction hole and a large number of conductive balls are continuously attached to the lower surface of the suction head, or when the conductive balls are attached to a position other than the suction hole. The suction head may rise as it is. In the method using the suction head as described above, a pickup error in which extra conductive balls adhere to the lower surface of the suction head is apt to occur, and the conductive balls may not be properly transferred one by one onto the electrodes of the work. There was a problem.

In view of this, the present invention removes the conductive balls that are excessively attached to the lower surface of the suction head due to a pickup error, and can transfer the conductive balls onto the electrodes of the workpiece correctly. And to provide a transfer method.

[0007]

According to a first aspect of the present invention, there is provided a conductive ball transfer device having a suction head having a plurality of suction holes for sucking the conductive balls formed on a lower surface thereof, and a ball supplying the conductive balls. A supply unit, a positioning unit for positioning the work, a vertical movement unit for moving the suction head up and down, a moving unit for moving the suction head in the horizontal direction, and an extra attachment other than the suction holes on the lower surface of the suction head. A removal section for removing the conductive balls is provided, and the removal section is provided with projection rows in the X and Y directions having projections corresponding to the pitch of the suction holes of the suction head.

According to a second aspect of the present invention, there is provided a conductive ball transfer method in which conductive balls in a ball supply portion are transferred to a work by a suction head having a plurality of suction holes for sucking the conductive balls formed on a lower surface thereof. A method for transferring a conductive ball, wherein the suction head having a conductive ball sucked on the lower surface thereof has projections provided in correspondence with the pitch of the suction holes of the suction head in the X and Y directions. Is attached to the lower surface of the suction head by moving the suction head horizontally in the X direction and the Y direction relative to the removal section. The conductive balls that have been removed are removed.

According to the present invention having the above structure, the suction head having the conductive balls vacuum-sucked on the lower surface is provided with the projections provided in correspondence with the pitch of the suction holes of the suction head. By moving the suction heads horizontally relative to the rows in the X and Y directions, it is possible to remove the conductive balls that are extraly attached to other than the suction holes.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a conductive ball transfer device according to an embodiment of the present invention, and FIG. 2A is a partial sectional view of a conductive ball removal portion of the conductive ball transfer device. (B) is a partial plan view of a conductive ball removing portion of the same conductive ball transfer device, FIGS. 3 and 4 are partial cross-sectional views of a ball supply portion of the same conductive ball transfer device, and FIG. FIG. 6 is a partial cross-sectional view of a conductive ball removing portion of the conductive ball transfer device, and FIG. 6 is a partial front view of a positioning table of the conductive ball transfer device.

First, the overall structure of the conductive ball transfer device will be described with reference to FIG. In FIG. 1, a positioning table 2 is provided on a base 1. The positioning table 2 is composed of a Y table 3 and an X table 4.
A holder 5 is provided on the X table 4, and the holder 5 holds the work 6. Therefore, the work 6 is positioned at a predetermined position by driving the positioning table 2.

A supply unit 10 for the conductive balls 7 is provided at the end of the base 1 opposite to the positioning table 2. The ball supply unit 10 includes a ball tank 11, and a plurality of layers of mesh plates 12 are horizontally spread inside the ball tank 11. The mesh plate 12 is provided with an innumerable number of openings whose size does not allow the conductive balls 7 to pass through. The conductive balls 7 are stored on the uppermost mesh plate 12. A nozzle 14 is arranged at the bottom of the ball tank 11, and the nozzle 14 is connected to a gas supply source (not shown). By supplying the gas to the nozzle 14, the gas blown upward from the nozzle 14 passes through the openings of the mesh plate 12 and is blown into the layer of the conductive balls 7 to fluidize the conductive balls 7.

Next, the suction head 31 for transferring the conductive balls 1 will be described. Reference numeral 20 shown in FIG. 1 is a moving means in the X direction (horizontal direction in FIG. 1), which moves the Y table 30 between the ball supply unit 10 and the positioning table 2. The Y table 30 includes a Y-axis motor 32,
The suction head 31 held on the Y table 30 is horizontally moved in the Y direction (the vertical direction of the drawing in FIG. 1).

A plurality of suction holes 3 are formed on the lower surface of the suction head 31.
1a is provided. The Y table 30 is the bracket 2
4 is mounted on a vertical guide rail 25 provided on the front surface of the unit 4 so as to be vertically movable. The Y table 30 has a nut 2
8 is integrally provided, and a vertical feed screw 26 is screwed into the nut 28. Therefore, the Z-axis motor 27
When the feed screw 26 rotates in the normal and reverse directions and rotates in the normal and reverse directions, the suction head 31 is guided by the guide rail 25 and moves up and down.
Therefore, the Z-axis motor 27 and the feed screw 26 are vertical moving means for moving the suction head 31 up and down.

A nut (not shown) provided on the back surface of the bracket 24 is screwed onto the horizontal feed screw 22.
Reference numeral 21 is a holding table for the feed screw 22. Therefore, when the X-axis motor 23 rotates forward and backward, the feed screw 22 rotates forward and backward, and the suction head 31 held by the bracket 24 horizontally moves between the positioning table 2 and the ball supply unit 10. Therefore, the moving means 20 in the X direction and the Y table 30 are moving means for moving the suction head 31 in the horizontal direction.

In FIG. 1, a ball supply unit 1 on a base 1
A removing portion 40 for the conductive balls 7 is arranged on the side of 0. The removing unit 40 removes the conductive balls 7 excessively attached to the lower surface of the suction head 31. As shown in FIGS. 1 and 2, a ball receiver 45 is placed on the box 41, and a base portion 42 is fixed in the ball receiver 45. A plate 43 is mounted on the base 42. The plate 43 has a suction hole 31 a of the suction head 31.
The pins 44 as the protrusions are erected at the same pitch p corresponding to the pitch p.

The pin 44, as shown in FIG.
Are arranged in an inverted L shape in the Y direction and in the Y direction, and respectively form a projection row 44X in the X direction and a projection row 44Y in the Y direction. As shown in FIG. 2A, the suction head 31 having the lower surface on which the conductive balls 7 are suctioned is positioned on the plate 43, and the suction head 31 is positioned so that the pin 44 is positioned in the middle of each suction hole 31a. To match. In this state, the suction head 31 is lowered to a height that keeps a predetermined interval at which the tip of the pin 44 does not contact the lower surface of the suction head 31, and the suction head 31 is sucked onto the plate 43 in the X direction and the Y direction. By horizontally moving by a distance corresponding to the width and depth length of the lower surface of the head 31, the conductive balls 7 attached to other than the suction holes 31a are scraped off by the pins 44 hitting the conductive balls 7 and sucked. It is removed from the lower surface of the head 31.

In this embodiment, one row of protrusions 44X in the X direction and one row of protrusions 44Y in the Y direction are provided, but a plurality of rows of protrusions 44X and 44Y may be provided. Good. In this case, the protrusion row 44
As the number of rows of X and 44Y increases, the suction head 31
Since it is sufficient that the distance for horizontally moving the removing unit 40 with respect to the removing unit 40 is short, the time required for the removing operation can be shortened.

This conductive ball transfer device has the above-mentioned structure, and its operation will be described below. First, in FIG. 1, the X-axis motor 23 is driven to move the suction head 31 above the ball supply unit 10. Then, the Z-axis motor 27 is driven to lower the suction head 31, and the lower surface of the suction head 31 is slightly sunk into the layer of the conductive balls 7 as shown in FIG. At this time, the nozzle 14 of the ball tank 11
More gas is blown upward (see arrow a), and the conductive balls 7 are fluidized by the flow of this gas. Therefore, the conductive ball 7 is blown up, hits the lower surface of the suction head 31 and is vacuum-sucked in the suction hole 31a.

At this time, as shown in FIG. 4, the suction head 31 may ascend while the extra conductive balls 7 are attached to positions other than the suction holes 31a on the lower surface of the suction head 31. Although FIG. 4 shows an example in which one extra conductive ball 7 is attached, in addition to this example, in the case where a plurality of conductive balls 7 are attached in series, the extra conductive balls 7 are attached.
There are various modes of attachment.

Conductive balls 7 attached in such an extra manner
Are removed by the removing unit 40. First, the suction head 31 that has suctioned the conductive balls 7 is moved to above the removing unit 40, and then the suction head 31 is lowered with respect to the plate 43. At this time, each pin 44 is attached to the suction head 3
The suction head 3 is positioned so as to be located in the middle of the first suction hole 31a.
Align 1 Then, the suction head 31 is lowered to a height position where the tip end of the pin 44 does not contact the lower surface of the suction head 31, and the suction head 31 is moved to the plate 4 while keeping the distance between the suction head 31 and the plate 43 at a predetermined distance.
3 is moved horizontally in the X and Y directions by a predetermined distance. As a result, as shown in FIG. 5, the conductive balls 7 (shown by broken lines) that are excessively attached to positions other than the suction holes 31a are scraped off by the pins 44 of the protrusion rows 44X and 44Y (arrows). (see c), and is collected in the ball receiver 45.

As described above, the suction heads 31 which have picked up the conductive balls 7 by vacuum suction one by one in all the suction holes 31a are lifted from the removing section 40 and then horizontally moved above the positioning table 2. Next, the suction head 31 descends onto the work 6 held by the holder 5, and
As shown in (4), the vacuum suction is released, the conductive balls 7 are transferred onto the electrodes 6a, and thereafter, the conductive balls 7 are raised to complete the transfer of the conductive balls 7.

The present invention is not limited to the above embodiment. For example, in the above embodiment, the conductive ball removing portion 40 is fixed, and the suction head 3 is attached to the removing portion 40.
1, the removal unit 40 is movable, and the suction head 3 is stationary on the ball supply unit 10.
The removing unit 40 may be moved with respect to 1.

[0024]

According to the present invention, the suction head, which has sucked the conductive balls in the ball supply portion, is moved down with respect to the conductive ball removing portion, and the protrusions provided corresponding to the pitch of the suction holes are formed. Since the suction head is moved in the X and Y directions relative to the projection rows in the X and Y directions, the extra conductive balls attached to other than the suction holes of the suction head can be securely and swiftly attached. Therefore, it is possible to surely transfer the conductive balls one by one onto the electrodes of the work.

[Brief description of drawings]

FIG. 1 is a front view of a conductive ball transfer device according to an embodiment of the present invention.

2A is a partial cross-sectional view of a conductive ball removing portion of a conductive ball transfer device according to an embodiment of the present invention. FIG. 2B is a conductive ball transfer according to an embodiment of the present invention. Partial plan view of conductive ball removal section of device

FIG. 3 is a partial cross-sectional view of a ball supply unit of a conductive ball transfer device according to an embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of a ball supply unit of the conductive ball transfer device according to the embodiment of the present invention.

FIG. 5 is a partial cross-sectional view of a conductive ball removing portion of the conductive ball transfer device according to the embodiment of the present invention.

FIG. 6 is a partial front view of a positioning table of the conductive ball transfer device according to the embodiment of the present invention.

[Explanation of symbols]

1 base 2 Positioning table 6 work 7 conductive balls 10-ball feeder 11 ball tank 23 X-axis motor 27 Z-axis motor 31 Suction head 31a adsorption hole 32 Y-axis motor 40 Remover 44 pin 44X, 44Y Projection row

Claims (2)

(57) [Claims] 1. A suction head having a plurality of suction holes for sucking conductive balls formed on a lower surface thereof, a ball supply unit for supplying the conductive balls, and a positioning unit for positioning a work.
A vertical moving means for moving the suction head up and down, a moving means for moving the suction head in a horizontal direction, and a removing portion for removing the conductive balls that are extraly attached to other than the suction holes on the lower surface of the suction head, A transfer device for conductive balls, characterized in that a row of protrusions in the X and Y directions having protrusions corresponding to the pitch of the suction holes of the suction head is provided in the removing portion. 2. A conductive ball transfer method for transferring a conductive ball of a ball supply unit onto a work by means of a suction head having a plurality of suction holes for sucking conductive balls formed on a lower surface thereof. The adsorption head that adsorbs the conductive balls is kept at a predetermined distance from a removal portion that has a protrusion row in the X direction and a Y direction that has protrusions provided corresponding to the pitch of the adsorption holes of the adsorption head. And moving the suction head horizontally relative to the removing portion in the X direction and the Y direction, thereby removing the conductive balls excessively attached to the lower surface of the suction head. Transfer method for conductive balls.