JP3246486B2 - 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. 6 is a 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.

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 to the suction hole 7 and picked up.

[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.

[0006] Thereafter, the head 6 descends and rises 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. The ball 1 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 Accordingly, the present invention is to provide a solder ball mounting apparatus and a mounting method capable of eliminating pick-up errors and mounting errors of solder balls and eliminating the need for air pressure feeding.

[0009]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a solder ball in which a plurality of solder balls stored in a storage portion are vacuum-sucked to suction holes formed in a plurality of lower surfaces of a head and mounted on a work. Wherein the head is provided with a vibration means, and a vibration frequency switching means of the vibration means is provided.

The present invention also provides a method of mounting a solder ball, wherein a plurality of solder balls stored in a storage section are vacuum-sucked into suction holes formed in a plurality of lower surfaces of a head and mounted on a work. The vibration frequency of the vibration means provided on the head is switched by the frequency switching means, and when the solder balls in the storage section are vacuum-sucked, the head is vibrated at a low frequency to mount the solder balls on the work. In this case, the head is vibrated at a high frequency.

In the above configuration, when the solder balls in the storage section are vacuum-sucked, the head is vibrated at a low frequency so that the solder balls are reliably sucked into the suction holes and picked up. When mounting the solder ball on the work, the head is vibrated at a high frequency so that the solder ball is surely dropped from the suction hole and mounted on the work.

[0012]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a solder ball mounting apparatus according to an embodiment of the present invention, FIG. 2 is a block diagram of the head and its driving means, FIG. 3 is a partially enlarged sectional view of a suction hole of the head, and FIG. FIG. 5 is a partial cross-sectional view of the solder ball during pickup, and FIG.

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 formed by attaching a suction pad 33 to a lower portion of a case 31 with an elastic sheet 32 interposed therebetween (see also FIG. 2). The right end of the suction pad section 33 extends rightward, and a second vibrator 34 is provided on the upper surface thereof. A large number of suction holes 35 (FIG. 3) for vacuum-sucking the solder balls 1 are formed on the lower surface of the suction pad portion 33 in a matrix. The lower portion of the suction hole 35 is a tapered surface 35a.

In FIG. 2, the second vibrator 34 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, and sets a low frequency of 500 Hz or less at the time of pickup, and sets an ultrasonic vibration of about 20 KHz at the time of mounting.

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. When the vacuum device 43 is driven,
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. At this time, the first vibrator 14 is driven and the container 13 is vibrating, and the solder ball 1 in the container 13 is flowing due to the vibration. Also in this case,
As shown in FIG. 4A, the head 30 is lowered while driving the second vibrator 34 to vibrate the suction pad 33 at a low frequency of about 500 Hz. And FIG.
When the lower surface of the suction pad 33 contacts the solder ball 1 in the container 13 as shown in FIG. 3B, the suction pad portion 33 is vibrating and the solder ball 1 is flowing.
As shown in (1), the solder ball 1 is guided to the suction hole 35 along the tapered surface 35a, and is reliably sucked into the suction hole 35 by vacuum. Next, as shown in FIG. 4C, the head 30 moves up,
The solder ball 1 is picked up.

Since the solder balls 1 are likely to flow when 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. 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. 5 shows the state at this time. When the solder ball 1 is mounted on the electrode 27 of the substrate 26,
By driving the second vibrator 34 to vibrate the suction pad 33 of the head 30, the solder ball 1 can be reliably dropped from the suction hole 35 and mounted on the electrode 27. In this case, if the vibration frequency of the suction pad section 33 is switched and ultrasonic vibration is performed 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 second
Of the vibrator 34 is stopped, and the head 30 is returned to above the container 13 shown in FIG. 1, and the above-described operation is repeated.

As described above, when the solder ball 1 in the container 13 is vacuum-sucked,
By vibrating the head 30 at a low frequency by the second vibrator 34, 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 ultrasonically vibrated at a high frequency by the second vibrator 34, so that the solder ball 1 vacuum-adsorbed to the lower surface of the head 30 is placed on the lower surface of the head 30. And can be reliably transferred to the substrate 26.

If the means for switching the vibration frequency of the head 30 is provided as described above, the first vibrator 14 for vibrating the container 13 can be dispensed with.
4, the container 13 may be vibrated during pickup. According to the present invention, the air for flowing the solder ball in the storage portion of 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, it is possible to reliably pick up a solder ball by vacuum-sucking the suction hole, and to drop the solder ball from the suction hole and mount it on a work. Further, air for flowing the solder ball in the storage portion of the solder ball can be eliminated.

[Brief description of the drawings]

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

FIG. 2 is a block diagram of a head of a solder ball mounting apparatus and a driving unit thereof according to an embodiment of the present invention;

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

FIG. 4 is a partial cross-sectional view of the solder ball mounting apparatus according to one embodiment of the present invention when the solder ball is picked up;

FIG. 5 is a front view of a main part when the solder ball mounting apparatus according to the embodiment of the present invention is mounted.

FIG. 6 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 (storage part) 14 First vibrator 20 Positioning part 26 Substrate 30 Head 34 Second vibrator 35 Suction hole 35a Tapered surface 61 Control part 62 Oscillator 63 Amplifier

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H05K 3/34 B23K 3/06 B25J 15/06 B65G 47/91 H01L 21/60

Claims (3)

(57) [Claims] An apparatus for mounting a solder ball, wherein a plurality of solder balls stored in a storage section are vacuum-sucked into suction holes formed in a plurality of lower surfaces of a head and mounted on a work, wherein the head is vibrated. And means for switching the vibration frequency of the vibration means. 2. The method according to claim 1, wherein the head is vibrated at a low frequency when the solder balls in the storage section are vacuum-sucked, and the head is vibrated at a high frequency when the solder balls are mounted on the work. The solder ball mounting device according to claim 1, wherein 3. A method for mounting a solder ball, wherein a plurality of solder balls stored in a storage section are vacuum-sucked into suction holes formed in a plurality of lower surfaces of the head and mounted on a work, wherein the solder balls are provided on the head. The vibration frequency of the vibrating means is switched by the frequency switching means, the head is vibrated at a low frequency when the solder balls in the storage section are vacuum-sucked, and when the solder balls are mounted on the work, A method for mounting a solder ball, wherein the head is vibrated at a high frequency.