JP3397093B2 - 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.

In this method, conductive balls stored in a container or the like are vacuum sucked and picked up by 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, it takes time for the conductive balls to be vacuum-sucked in the suction holes, and the suction head may rise without vacuum-sucking the conductive balls depending on the suction holes. On the contrary, a plurality of conductive balls may be vacuum-sucked in one suction hole, and a large number of conductive balls may be continuously attached to the lower surface of the suction head. In the method using the suction head as described above, pick-up mistakes are likely to occur, and the conductive balls are not formed on the electrode of the work piece.
There was a problem that they were not transferred correctly one by one.

Therefore, the present invention provides a conductive ball transfer device and transfer method capable of eliminating a conductive ball pickup error and reliably transferring the conductive ball onto an electrode of a workpiece. With the goal.

[0006]

According to another aspect of the present invention, there is provided a conductive ball transfer device, wherein a suction head having a plurality of suction holes for vacuum-sucking the conductive balls is formed on a lower surface thereof, and the conductive balls are stored. The ball tank and the upper part of this ball tank,
Comprising a plate attached horizontally to a position covered by the reservoir electrically conductive balls, and a vertical movement means for the pre-Symbol suction head is vertically movable relative to the plate, the plate
Guides formed corresponding to the positions of the suction holes of the suction head.
In the through hole through which the electrically conductive ball passes and in the adjacent through hole
The suction head protrudes upward to a position between
Exist in a position other than the suction holes when descending toward
Equipped with multiple protrusions that laterally eliminate the conductive balls
I got it.

[0007]

According to a second aspect of the present invention, there is provided a method for transferring conductive balls, wherein conductive balls stored in a ball tank are transferred onto a work by a suction head having a plurality of suction holes formed on a lower surface thereof. A through-hole that is provided above the ball tank and that is adjacent to a through-hole through which the conductive ball passes at a position corresponding to the suction hole of the suction head.
Covering the upper surface of a horizontal plate having a plurality of protrusions protruding upward at a position between them with a layer of conductive balls;
A step of vacuum suction conductive balls the suction head to the suction hole of the suction head is lowered relative to the plate
And by lowering the suction head, the suction holes
The conductive balls at the position other than the projection
It includes a step of laterally excluding and pushing back into the through hole, and a step of raising the suction head to pick up the conductive ball vacuum-sucked.

According to the present invention having the above-mentioned structure, the upper surface of the horizontal plate having through holes through which the conductive balls pass is formed at a position corresponding to the suction holes of the suction head, and the upper surface of the horizontal plate is covered with a layer of the conductive balls. By pushing back the extra conductive balls into the through holes when vacuum-adsorbing the conductive balls with,
It is possible to prevent extra conductive balls from adhering to the suction tool.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment 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, FIG. 2 is a sectional view of a ball tank of the conductive ball transfer device, and FIG. 3 is a transfer of the conductive ball. FIG. 4 and FIG. 5 are partial cross-sectional views of the ball tank of the conductive ball transfer device, and FIG. 6 is a partial front view of the 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.

On the side of the positioning table 2 on the base 1, a ball tank 1 of conductive balls 7 made of a container 11 is provided.
0 is set. The ball tank 10 will be described below with reference to FIGS. 2 and 3. In FIG. 2, a plurality of layers of mesh plates 12 are horizontally spread inside the container 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 provided at the bottom of the container 11, and the nozzle 14 is provided with a gas supply source (not shown) through a pipe 15.
It is connected to the. 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.

Above the uppermost mesh plate 12, the plate 1 is placed at a position covered with a layer of conductive balls 7.
3 are arranged horizontally. As shown in FIG. 3, the plate 13 is formed with a large number of through holes 13a having a size through which the conductive balls 7 can pass, and the positions of the through holes 13a correspond to the positions of the suction holes 31a on the lower surface of the suction head 31. It has been done.

Further, a large number of pins 13b as projecting portions are provided upright at intermediate positions between the adjacent through holes 13a. The pin 13b plays a role of eliminating the conductive ball 7 so that the conductive ball 7 does not exist at a position other than immediately below the suction hole 31a of the suction head 31 when the conductive ball 7 is sucked. The plate 13 is fixed to the container 11 by a bracket 16, and when the conductive balls 7 are vacuum-sucked, the suction head 31 is aligned with the plate 13 so that the suction holes 31a and the through holes 13a are aligned with each other. To do.

Next, the suction head 31 on which the conductive balls 7 are transferred will be described. Reference numeral 20 shown in FIG. 1 is a moving means for moving the suction head 31 between the ball tank 10 and the positioning table 2. The suction head 31 is a block 3
The suction head 31 has a plurality of suction holes 31a. The block 30 is vertically movably mounted on a vertical guide rail 25 provided on the front surface of the bracket 24. A nut 28 is integrally provided on the block 30, and a vertical feed screw 26 is screwed onto the nut 28. Therefore, when the Z-axis motor 27 is driven forward and backward and the feed screw 26 rotates forward and backward, 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 33 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 tank 10.

This conductive ball transfer device has the above-mentioned structure, and its operation will be described with reference to the drawings.
First, in FIG. 1, the X-axis motor 23 is driven to move the suction head 31 above the ball tank 10. So Z
The shaft motor 27 is driven to lower the suction head 31, and the lower surface of the suction head 31 is slightly submerged in the layer of the conductive balls 7 of the ball tank 10 as shown in FIG. At this time, gas is blown upward from the nozzle 14 of the ball tank 10 (see arrow a), and the conductive balls 7 are fluidized by the flow of gas. Therefore, the conductive balls 7
Is blown up and hits the lower surface of the suction head 31. Among these conductive balls 7, the conductive ball 7 that abuts the suction hole 31a is captured by the suction force because the suction hole 31a is vacuum-sucked (see arrow b), and the suction hole 31a is immediately vacuumed. Adsorbed.

Next, when the suction head 31 is gradually lowered while continuing the vacuum suction of the suction holes 31a, the pins 13b come close to the lower surface of the suction head 31 as shown in FIG. Therefore, the conductive ball 7 is provided at the position of the pin 13b, that is, at a position other than the suction hole 31a of the suction head 31.
Cannot exist, and on the lower surface of the suction head 31,
The conductive balls 7 are present just below the suction holes 31a. That is, the conductive ball 7 that was initially positioned to overlap the pin 13b is laterally removed by the pin 13b when the suction head 31 descends, and the suction head 31 further descends to enter the through hole 13a. It is pushed back and forcibly moved below the plate 13.

As described above, the ball tank 10 is provided with the plate 13 having the through holes 13a corresponding to the positions of the suction holes 31a of the suction head 31, and the conductive fluidized by blowing up the gas during vacuum suction. Ball 7 through hole 13a
To the lower surface of the suction head 31 through the pin 13b, and by removing the conductive balls 7 existing other than the position of the suction hole 31a by the pin 13b, the suction holes 31a of the suction head 31 are electrically conductive. Sex ball 7
Can be vacuum-adsorbed one by one quickly and correctly.

As described above, the suction heads 31 which correctly pick up the conductive balls 7 by vacuum suction one by one in all the suction holes 31a are lifted from the plate 13 and then horizontally moved above the positioning table 2. Next, the suction head 31 descends onto the substrate 6 held by the holder 5, and
As shown in FIG. 5, the conductive balls 7 are transferred onto the electrodes 6a and then moved upward to complete the transfer of the conductive balls 7.

The present invention is not limited to the above-described embodiment, and for example, the pin 13b erected on the plate 13 is used in the above-described embodiment as a protrusion for excluding the conductive ball 7, but it is necessary. May be one that does not allow the conductive balls to exist at a predetermined position on the plate, and may be, for example, one in which a tapered projection is provided around the through hole 13a.

[0022]

According to the present invention , the conductive balls are correctly vacuum-sucked one by one in each suction hole. Furthermore, since a protruding part that eliminates the extra conductive balls is provided in the middle of the adjacent through holes, the extra conductive balls are prevented from adhering to the suction head, and one conductive ball is surely attached. It can be transferred to the electrodes of the workpiece one by one.

[Brief description of drawings]

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

FIG. 2 is a sectional view of a ball tank of the conductive ball transfer device according to the embodiment of the present invention.

FIG. 3 is a perspective view of a ball tank of the conductive ball transfer device according to the embodiment of the present invention.

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

FIG. 5 is a partial cross-sectional view of the ball tank 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]

2 Positioning table 6 work 7 conductive balls 10 ball tank 11 containers 12 mesh plate 13 plates 13a through hole 13b protrusion 14 nozzles 20 means of transportation 23 X-axis motor 27 Z-axis motor 31 Suction head 31a adsorption hole

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/60 H01L 23/12 H05K 3/34 505 B23K 3/06 B23P 21/00 305 B25J 15/06

Claims (2)

(57) [Claims] 1. A suction head having a plurality of suction holes for vacuum-sucking conductive balls formed on a lower surface thereof, a ball tank for storing the conductive balls, and a conductive tank stored above the ball tank. comprising a plate attached horizontally to a position covered by the ball, and a vertical movement means for the pre-Symbol suction head is vertically movable relative to the plate, the intake to the plate
Of the conductive holes formed at the positions of the suction holes of the deposition head.
Between the through holes through which the holes pass and the adjacent through holes that are adjacent to each other.
The suction head toward this plate.
When it descends once, the guides existing in positions other than the suction holes are
An electro- conductive ball transfer device comprising a plurality of protrusions for laterally removing the electro-conductive balls. 2. A conductive ball transfer method for transferring conductive balls stored in a ball tank onto a work by means of a suction head having a plurality of suction holes formed on the lower surface thereof. The penetrating hole which is provided adjacent to the through hole through which the conductive ball passes at a position corresponding to the suction hole of the suction head.
A step of covering the upper surface of the horizontal plate having a plurality of protrusions are formed to protrude upward in an intermediate position of the hole with a layer of conductive balls, the suction head is lowered to the suction head relative to the plate Vacuum suction of conductive balls to the suction holes of
And the step of lowering the suction head
The conductive balls existing at positions other than the suction holes are attached to the protrusions.
A method of transferring conductive balls, the method including the steps of laterally excluding and pushing back into the through holes, and raising the suction head to pick up the conductive balls vacuum-sucked.