JP3164109B2 - Solder ball mounting device and mounting 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 solder ball mounting apparatus and method for mounting solder balls on a work such as a substrate.

[0002]

2. Description of the Related Art As means for forming bumps (protruding electrodes) on a work such as a substrate or a chip, a solder ball formed of a solder material is mounted on the work, and the solder ball is heated and melted and solidified. It is known to form bumps. The solder ball mounting device that mounts the solder ball on the work is such that the solder ball is vacuum-adsorbed to the suction hole of the head and picked up, and then the head is moved above the work to transfer the solder ball to the work. Has become.

FIG. 7 is a cross-sectional view of a main part of a conventional solder ball mounting device at the time of pickup. Reference numeral 1 denotes a solder ball, which is stored in a container 2. Reference numeral 3 denotes a receiving stand for the container 2, and air is pressure-fed from the compressor 4. A hole 5 is opened in the lower surface of the container 2, and air blown into the receiving portion 3 blows up into the container 2 from the hole 5, so that the solder balls 1 in the container 2 are fluidized. I do. Reference numeral 6 denotes a head, on the lower surface of which are formed a large number of suction holes 7 for sucking the solder ball 1 by vacuum. The head 6 is connected to a vacuum device (not shown), and drives the vacuum device to vacuum-suck the solder ball 1 into the suction hole 7. The head 6 is held by a moving unit (not shown), and is a work positioned by a container 2 serving as a storage unit for the solder balls 1 and a positioning unit (not shown) by driving the moving unit. Reciprocate between substrates.

In the above configuration, the air is blown up into the container 2 so that the solder ball 1 flows in the container 2. Then, by lowering and raising the head 6, the solder ball 1 is vacuum-sucked into the suction hole 7 and picked up.
Subsequently, the head moves above the work, and performs the lowering / upward operation again, thereby mounting the solder ball 1 vacuum-adsorbed to the suction hole 7 on the work.

[0005]

In the above-mentioned conventional apparatus, the air is blown up to the container 2 to fluidize the solder ball 1, so that the solder ball 1 can be easily vacuum-adsorbed to the many suction holes 7. . However, in the above-described conventional device, the solder ball easily adheres to the lower surface of the head 6 other than the suction hole 7 (see the solder ball indicated by reference numeral 1 '). If the unnecessary solder balls 1 'are attracted to the lower surface of the head 6, the solder balls 1' are also mounted on the work. Further, if the solder ball 1 is merely fluidized, the solder ball 1 is difficult to be vacuum-sucked in all the suction holes 7 and the suction hole 7 in which the solder ball 1 is missing is easily generated. It was easy to do.

The head 6 moves downward and upward above the work, and releases the vacuum suction state of the solder ball 1 so that the solder ball 1 is mounted on the work. Was not mounted on the work, and a mounting error was likely to occur because some solder balls 1 remained attached to the head 6.

Further, since the solder ball mounting apparatus consumes a large amount of air, it is easy for the equipment other than the solder ball mounting apparatus in the installation factory to be short of air, and air is press-fitted into the container 2. Therefore, there is a problem that the solder ball 1 is easily oxidized, and as a result, a defective bump is easily generated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solder ball mounting apparatus and a mounting method which can eliminate pick-up errors and mounting errors of solder balls and can eliminate the need for air pressure feeding.

[0009]

SUMMARY OF THE INVENTION The present invention relates to an apparatus for mounting a solder ball, in which a plurality of solder balls stored in a container are vacuum-sucked into suction holes formed on a lower surface of a head and mounted on a work. The container is supported by an elastic member, and first vibrating means for vibrating the container is provided, and the head is provided with a second vibrating means having a higher vibration frequency than the first vibrating means. The first vibration means is driven to vibrate the container, and the vibration causes the solder ball fluidized in the container to be vacuum-sucked to the suction hole.

Further, according to the method of mounting a solder ball of the present invention, the container supported by the elastic member is vibrated by the first vibrating means so that the solder ball stored in the container is fluidized, and the fluidized solder ball is provided. When a plurality of suction holes are formed on the lower surface of the head and vacuum picked up, and then the picked-up solder balls are mounted on the work, the head is vibrated by the second vibrating means to move the solder balls from the suction holes. It is made to fall off.

In the above configuration, when picking up the solder balls in the container, the first vibrating means is driven to fluidize the solder balls in the container, and the fluidized solder balls are vacuum-adsorbed to the suction holes of the head. I do. In this case, the container is desirably vibrated in a resonance state. When the solder ball is mounted on the work, the second vibrating means is driven to reliably drop the solder ball from the suction hole of the head and mount the solder ball on the work. In this case, preferably, the head is ultrasonically vibrated at a high frequency by the second vibrating means.

[0012]

(Embodiment 1) FIG. 1 is a side view of a solder ball mounting apparatus according to Embodiment 1 of the present invention, and FIG.
(A) and (b) are cross-sectional views of main parts at the time of the pickup, FIG. 3 is a partially enlarged cross-sectional view of suction holes of the head, and FIG. 4 is a front view of main parts at the time of mounting.

In FIG. 1, reference numeral 11 denotes a base,
2 are installed. The receiving table 12 is provided with a container 13 as a storage section for the solder balls 1. A first vibrator 14 is connected to the lower surface of the container 13, and the side surface is supported by an elastic member 15 such as rubber or a spring. Therefore, when the first vibrator 14 is driven, the container 13
Vibrates, and the solder balls 1 in the container 13 flow in the container 13 due to the vibration.

Reference numeral 20 denotes a substrate positioning portion, which is formed by stacking an X table 21 and a Y table 22.
Reference numerals 23 and 24 denote driving motors for the X table 21 and the Y table 22. A clamper 25 is provided on the Y table 22. The clamper 25 clamps and fixes the substrate 26 from right and left. Therefore, X table 21 and Y
When the table 22 is driven, the substrate 26 moves horizontally in the X direction and the Y direction, and its position is adjusted.

Reference numeral 30 denotes a head, which is constituted by attaching a suction pad portion 33 to a lower portion of a case 31 with an elastic sheet 32 interposed therebetween (see also FIG. 2A). The right end of the suction pad portion 33 extends rightward, and a second
Is provided. In addition, the suction pad section 33
A large number of suction holes 35 (FIG. 3) for vacuum-sucking the solder balls 1 are formed in a matrix on the lower surface.

In FIG. 1, a head 30 is provided with a shaft 36.
Are held in the block 37 via the. Reference numeral 38 denotes a support frame, and a vertical guide rail 39 is provided on the front surface thereof.
Is provided. The block 37 is mounted on a guide rail 39 so as to be able to move up and down. Nut 4 in block 37
0 is connected. The nut 40 has a vertical feed screw 4
1 is screwed. When the motor 42 is driven and the feed screw 41
When rotates, the block 37 moves up and down along the guide rail 39, and the head 30 also moves up and down. A vacuum device 43 is connected to the head 30 via a tube 44. By driving the vacuum device 43,
The solder ball 1 is vacuum-sucked into the suction hole 35.

Reference numeral 50 denotes a horizontally long frame, on the front of which a horizontal ball screw 51 is provided. A nut (not shown) provided on the back surface of the support frame 38 is screwed to the ball screw 51. When the motor 52 is driven to rotate the ball screw 51, the support frame 38 moves horizontally in the X direction along the ball screw 51, whereby the head 30 reciprocates between the container 13 and the substrate 26. That is, the ball screw 51 and the motor 52 constitute a moving unit for moving the head 30 horizontally.

This solder ball mounting device has the above-described configuration, and the overall operation will be described next. As shown in FIG. 1, the head 30 is positioned above the container 13 and the motor 42 is driven forward. Then, the feed screw 41 rotates forward,
The head 30 moves down. In FIG. 2A, at this time, the first vibrator 14 is driven and the container 13 is vibrating.
Due to this vibration, the solder balls 1 in the container 13 are flowing. When the head 30 is lowered into the container 13 in this state, the solder balls 1 are vacuum-sucked into the suction holes 35. FIG.
FIG. 4 shows a state in which the solder ball 1 is vacuum-sucked in the suction hole 35. The solder ball 1 is guided by the tapered surface 35a of the suction hole 35 due to the flowing, so that the suction hole 35 is sucked.
Is reliably vacuum-adsorbed. In addition, since the solder balls 1 are likely to flow while the container 13 is resonating at a low frequency, it is desirable that the container 13 be vibrated in a resonance state.
The resonance frequency varies depending on the size, shape, material, and the like of the container 13, but generally, the resonance easily occurs in the range of 500 Hz to 30 Hz.

Next, in FIG. 2B, the first vibrator 1
4 stops driving, the motor 42 is driven in reverse to drive the head 30
Rises and picks up the solder ball 1.

Next, in FIG. 1, the motor 52 rotates forward, the ball screw 51 rotates forward, and the head 30
Move upwards to 6. Then, the motor 42 is driven forward to lower the head 30 so that the solder ball 1 lands on the electrode of the substrate 26, and then the vacuum suction state of the solder ball 1 by the vacuum device 43 is released. The head 30 is raised by driving, and the solder ball 1 is mounted on the substrate 26. FIG. 4 shows this state. When the solder ball 1 is mounted on the electrode 27 of the substrate 26, the second vibrator 34 is driven to drive the suction pad 3 of the head 30.
By vibrating 3, the solder ball 1 can be reliably dropped from the suction hole 35 and mounted on the electrode 27. In this case, if the suction pad portion 33 is ultrasonically vibrated at a high frequency of about 20 KHz, the solder ball 1 can be reliably dropped from the suction hole 35. When the solder ball 1 is mounted on the substrate 26 in this manner, the driving of the second vibrator 34 is stopped, and the head 30 is returned to the upper side of the container 13 shown in FIG. .

As described above, when the solder ball 1 in the container 13 is vacuum-sucked,
By vibrating the container 13 by the first vibrator 14 to fluidize the solder balls 1, the solder balls 1 can be reliably sucked and picked up in all the suction holes 35. When the solder ball 1 is mounted on the substrate 26, the head 30 is vibrated by the second vibrator 34 so that the solder ball 1 vacuum-adsorbed on the lower surface of the head 30 is dropped from the lower surface of the head 30. Transfer to the substrate 26 is ensured.

(Embodiment 2) FIG. 5 is a block diagram of a head and its driving means of a solder ball mounting apparatus according to Embodiment 2 of the present invention, and FIGS. It is principal part sectional drawing of. In FIG. 5, the second vibrator 3
Reference numeral 4 is connected to a drive circuit including a control unit 61, an oscillator 62, and an amplifier 63. The control unit 61 has a function of switching the vibration frequency.
Set to low frequency below 20Hz and 20KHz when mounted
Set to about ultrasonic vibration. The overall configuration of the solder ball mounting device of the second embodiment is the same as that of the first embodiment shown in FIG. 1, but the first vibrator 14 for vibrating the container 13 may be omitted.

Next, the operation will be described. FIG. 6 shows a pickup operation. First, as shown in FIG.
The second vibrator 34 is driven to set the suction pad 33 to 500
The head 30 is lowered while vibrating at a low frequency of about Hz. When the lower surface of the suction pad 33 comes into contact with the solder ball 1 in the container 13 as shown in FIG. 6B, the suction pad 33 vibrates. Is guided to the suction hole 35 along the line, and the vacuum suction is reliably performed on the suction hole 35. Next, FIG.
As shown in (c), the head 30 is raised and the solder ball 1
To pick up.

Next, as in the case of the first embodiment, the head 3
0 moves above the substrate 26, where the head 30 descends and transfers the solder ball 1 onto the electrode 27 of the substrate 26.
The operation at this time is the same as that of the first embodiment shown in FIG. 4, but in this case, the vibration frequency of the suction pad 33 is 20
Switch to ultrasonic vibration above KHz. If the means for switching the vibration frequency of the head 30 is provided as in the second embodiment, the first vibrator 14 for vibrating the container 13 can be unnecessary. In this case, too, the first vibrator 14 is provided. hand,
At the time of pickup, the container 13 may be vibrated. According to the present invention, air for flowing the solder ball in the reservoir (container) for the solder ball can be made unnecessary, but the blowing of the air is not prohibited.

[0025]

As described above, according to the present invention, when the solder ball is vacuum-adsorbed and picked up by the head, the container is vibrated by the first vibrating means. By resonating, the fluidized solder balls can be reliably sucked into the suction holes by vacuum suction and picked up. When the solder ball is mounted on the work, the head is vibrated by the second vibrating means, and in this case, preferably by ultrasonic vibration at a high frequency, the solder ball is securely dropped from the suction hole to ensure the work is removed. It can be mounted on. Further, air for flowing the solder balls in the container which is the storage portion of the solder balls can be made unnecessary.

[Brief description of the drawings]

FIG. 1 is a side view of a solder ball mounting device according to a first embodiment of the present invention.

FIG. 2A is a cross-sectional view of a main part of the solder ball mounting apparatus according to the first embodiment of the present invention at the time of pickup; FIG. 2B is a main part of the solder ball mounting apparatus according to the first embodiment of the present invention at the time of pick-up; Sectional view

FIG. 3 is a partially enlarged cross-sectional view of a suction hole of a head of the solder ball mounting device according to the first embodiment of the present invention.

FIG. 4 is a front view of a main part when the solder ball mounting device according to the first embodiment of the present invention is mounted.

FIG. 5 is a block diagram of a head of a solder ball mounting device and a driving means thereof according to a second embodiment of the present invention;

FIG. 6A is a sectional view of a main part of the solder ball mounting apparatus according to the second embodiment of the present invention at the time of pickup; and FIG. 6B is a main part of the solder ball mounting apparatus according to the second embodiment of the present invention at the time of pickup. Cross-sectional view (c) Cross-sectional view of a principal part of the solder ball mounting device according to the second embodiment of the present invention at the time of pickup.

FIG. 7 is a cross-sectional view of a main part of a conventional solder ball mounting device during pickup.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solder ball 13 Container 14 First vibrator 15 Elastic member 20 Positioning part 26 Substrate 30 Head 34 Second vibrator 35 Suction hole

Claims (7)

(57) [Claims] An apparatus for mounting a solder ball, wherein a plurality of solder balls stored in a container are vacuum-sucked into suction holes formed in a plurality of lower surfaces of a head and mounted on a work, wherein the container is made of an elastic member. And a first vibrating means for vibrating the container is provided, and a second vibrating means having a higher vibration frequency than the first vibrating means is provided on the head, wherein the first vibrating means is provided. Wherein the solder ball fluidized in the container by the vibration is vacuum-adsorbed to the suction hole while driving the container to vibrate the container. 2. A suction pad is provided below the head, the suction hole is formed in the suction pad, and the second vibrating means vibrates the suction pad. Solder ball mounting device. 3. The solder ball mounting apparatus according to claim 1, wherein said second vibration means vibrates ultrasonically. 4. The solder ball mounting apparatus according to claim 1, wherein said first vibration means vibrates said container in a resonance state. 5. The solder ball stored in the container is fluidized by vibrating the container supported by the elastic member by the first vibration means, and a plurality of fluidized solder balls are formed on the lower surface of the head. When the picked-up solder ball is picked up by vacuum suction and then mounted on a work, the head is vibrated by the second vibrating means to drop the solder ball from the suction hole. How to mount solder balls. 6. The solder ball mounting method according to claim 5, wherein said first vibration means vibrates said container in a low-frequency resonance state to fluidize the solder ball. 7. The solder ball mounting method according to claim 5, wherein said head is ultrasonically vibrated at a high frequency by said second vibrating means to drop the solder ball from the suction hole.