JP3067632B2 - Apparatus and method for mounting conductive ball - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for mounting a conductive ball for manufacturing a work with bumps.
It is about the law .

[0002]

2. Description of the Related Art As a method for manufacturing a work with bumps such as flip chips, a method using conductive balls such as solder balls is known. In this method, conductive balls are mounted on electrodes of workpieces such as chips and substrates, and then the conductive balls are heated, melted, and solidified to form bumps (protruding electrodes).
Is formed.

[0003]

The work has a large number of electrodes (generally several tens or more), and a minute conductive ball (generally having a diameter of 0 or 4 mm) is provided on the large number of electrodes. However, at present, the technology for mounting a large number of conductive balls on a large number of electrodes with good workability has not been established.

Accordingly, an object of the present invention is to provide a conductive ball mounting apparatus and a mounting method capable of mounting a large number of conductive balls on an electrode of a work with good workability.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a conductive ball supply unit, a missed ball detection unit, a remaining ball discharge unit detected by the missed ball detection unit, a work positioning unit, and the like. the juxtaposed on the same straight line, also provided a movable table along the positioning portion of the detecting means and the work of the supply unit and misses the ball, and reciprocates between the positioning portion and the supplying portion along the moving table And a mounting head for transferring and mounting the conductive ball provided in the supply unit to the work , wherein the detecting means for the missed ball is a light receiving element.
And a light-emitting element that irradiates light to this light-receiving element.
It is those that.

[0006]

According to the present invention, a mounting head is provided above a conductive ball supply unit, a misball detection unit, a misball discharge unit, and a work supply unit which are arranged on the same straight line. Can be mounted on the electrode of the workpiece with good workability by a simple operation of linearly reciprocating.

(Embodiment 1) Next, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 are side views of the conductive ball mounting apparatus according to the first embodiment of the present invention, FIG. 3 is a plan view of the same, FIG. 4 is a perspective view of the missed ball detecting means, and FIGS. FIG. 7 is an enlarged cross-sectional view of the lower portion of the mounting head.

In FIG. 1, reference numeral 1 denotes a solder ball as a conductive ball, which is stored in a container 2. Reference numeral 3 denotes a base on which the container 2 is placed. Vibration means for vibrating the container 2 and gas supply means for feeding gas into the container 2 are provided inside the base 3 to fluidize the solder balls 1 in the container 2. On the right wall of the container 2, a brush 4
Is projected upward. The container 2 and the base 3 constitute a supply unit for the solder balls 1.

In FIG. 1, reference numeral 10 denotes a work, which is clamped by a clamper 11 and positioned. The clamper 11 is supported by a column 13 erected on a base 12. The clamper 11, the base 12, and the support 13
This is the positioning part. A case 14 is provided between the container 2 and the work 10 as a discharge portion of the solder ball 1. In FIG. 4, brackets 15 and 16 are provided upright on both sides of the case 14. The light emitting element 17 is mounted on the inner surface of the bracket 15, and the light receiving element 18 is mounted on the inner surface of the bracket 16. The light emitting element 17 and the light receiving element 18 are connected to the detection unit 20 via a cable 19. The detection unit 20 is connected to the control unit 21. L is an optical path of light emitted from the light emitting element 17 to the light receiving element 18. The light emitting element 17 and the light receiving element 18 constitute an extra ball detecting means.

In FIG. 1, reference numeral 22 denotes a mounting head.
The mounting head 22 is held below the box 23. A motor 24 is provided above the box 23. The box 23 has built-in vertical movement means such as a feed screw driven by a motor 24.
When 4 is driven, the mounting head 22 moves up and down. As shown in FIG.
Are opened. The mounting head 22 is connected to a pneumatic unit (not shown). When the pneumatic unit is driven, the solder ball 1 is vacuum-adsorbed and held in the suction hole 25, and the solder ball is released by releasing the vacuum suction state. Drop 1

The box 23 is held on a horizontally long moving table 26 as moving means. The moving table 26 has a built-in feed screw mechanism. When the motor 27 is driven to operate the feed screw mechanism, the mounting head 22 moves between the container 2, the case 14, and the work 10 in the horizontal direction.

In FIGS. 2 and 3, reference numeral 40 denotes a reservoir for the flux 41, which is formed of a container having a shallow bottom.
Reference numeral 42 denotes the cradle. Reference numeral 43 denotes a coating head, on the lower surface of which a transfer pin 44 protrudes. Transfer pin 4
Reference numeral 4 denotes a plurality of projections corresponding to the electrodes of the work 10. The coating head 43 is held in the box 23a. The box 23a is held on a second moving table 26a parallel to the first moving table 26. FIG.
, A is a line on which the first moving table 26 is arranged,
B is an arrangement line of the second moving table 26a. The box 23a has the same structure as the box 23 of the mounting head 22. The second moving table 26a has the same structure as the first moving table 26. When the motor 24a is driven, the coating head 43 moves up and down, and when the motor 27a is driven, the coating head 43 reciprocates in the horizontal direction between the storage section 40 of the flux 41 and the work 10 indicated by a chain line. I do.

The coating head 43 stops above the storage portion 40 of the flux 41 and performs a descending operation so that the lower end of the transfer pin 44 is immersed in the flux 41 (the coating head indicated by a chain line in FIG. 2). 43). Next, after the coating head 43 moves up, the coating head 43 moves above the work 10 shown by a chain line in FIG.
Is applied. Workpiece 10 coated with flux 41
Is sent to the position shown by the solid line in FIG. 3, where the solder ball is mounted.

This conductive ball mounting device is configured as described above, and the operation will be described next. In FIG. 1, the mounting head 22 moves above the container 2 and performs a lowering / elevating operation there.
The solder ball 1 is vacuum-adsorbed and picked up. FIG.
Shows the lower part of the mounting head 22 from which the solder ball 1 has been picked up. As shown in the drawing, one solder ball 1 is vacuum-sucked to each suction hole 25. In FIG. 7, however, one extra conductive ball (extra ball) 1A is attached. . If the extra ball 1A is mounted on the work 10, the work 10 becomes defective. Therefore, the extra ball 1A must not be mounted on the work 10. The extra balls 1A are generated due to adhesion of solder balls due to static electricity, vacuum leakage of the suction holes 25, and the like.

In FIG. 1, the mounting head 22 picking up the solder ball 1 moves rightward toward the work 10 (see also FIG. 2). At this time, the mounting head 2
2 passes above the brush 4, and the upper end of the brush 4 slides on the solder ball 1 held on the lower surface of the mounting head 22. Among the solder balls shown in FIG. 7, the normal solder ball 1 which has been correctly vacuum-sucked directly to the suction hole 25 is strongly vacuum-sucked and held, so that it does not fall even when the brush 4 slides, but the extra ball 1A Is held by a weak force due to static electricity or the like. In addition, as in the first embodiment,
If the brush 4 is provided on the moving path of the mounting head 22 and the brush 4 is slid on the solder ball 1, the solder ball 1
During the transfer of the extra ball 1A to the work 10, the extra ball 1A can be easily dropped and removed. Further, by providing the brush 4 in the container 2, the extra ball 1 </ b> A dropped by the brush 4 can be collected in the container 2 as it is.

Next, the mounting head 22 passes between the light emitting element 17 and the light receiving element 18 as shown in FIG. FIG.
As shown in FIG. 7 and FIG. 7, the level of the mounting head 22 is
The normal solder ball 1 does not block the optical path L, but the extra ball 1 protrudes downward from the normal solder ball 1.
A is set to the height at which light is shielded. Of course, the level of the mounting head 22 is controlled by driving the motor 24. As described above, the extra ball 1A is slid and dropped by the brush 4, but the slid drop is not always successful, and the extra ball 1A still remains as shown in FIGS. You may have. Such an extra ball 1A is detected by blocking the light path L.

As described above, when the extra ball 1A is detected, various methods are available, some of which will be described below. First, the first method is to stop the mounting head 22 above the case 14, and then operate the pneumatic unit (not shown) in the opposite direction, thereby causing the suction holes 25 to move.
By blowing air from the device or releasing the vacuum suction state, all the solder balls 1 and the extra balls 1A held by the mounting head 22 are discharged to the case 14 and collected. Then, the mounting head 22 is returned above the container 2, and the pickup operation is performed again.

In the second method, the mounting head 22 is returned above the container 2 and is moved again above the brush 4, so that the extra ball 1A is slid and dropped by the brush 4 again.

The third method is to return the mounting head 22 to a position above the container 2 and lower the mounting head 22 so that the lower surface of the mounting head 22 enters the layer of the solder balls 1 stored in the container 2 in a large amount. In this state, the extra ball 1A is forcibly shaken by driving the motor 27 to perform the scrubbing operation of the mounting head 22 in the lateral direction. As described above, the extra ball 1A can be removed by various methods.

The mounting head 22 from which the extra balls 1A have been removed moves above the work 10 in FIG. Then, the mounting head 22 descends and the solder balls 1
Is landed on the electrode of the work 10. Prior to this, the flux 41 is applied on the electrodes of the work 10 in advance by the application head 43. Next, when the vacuum suction state of the solder balls 1 is released and the mounting head 22 is raised, the solder balls 1 are mounted on the electrodes of the work 10.
The work 10 on which the solder balls 1 are mounted is sent to a heating furnace (not shown), and the solder balls 1 are heated, melted and solidified to form bumps.

When the solder ball 1 is mounted on the work 10 as described above, the mounting head 22 is
2 returns above the container 2. FIG. 6 shows the mounting head 22 passing over the box 14 during this return.
Reference numeral 1B denotes a solder ball remaining on the lower surface of the mounting head 22 (hereinafter, referred to as a “remaining ball”). Remaining ball 1B
Are those that failed to be mounted on the work 10 and remained on the lower surface of the mounting head 22. In the present invention, the extra balls 1A and the remaining balls 1B are collectively referred to as miss balls.

The remaining ball 1B is detected by blocking the light path L from light. By driving the motor 24, the height of the mounting head 22 is set slightly lower on the return path than on the forward path, or by slightly raising the light emitting element 17 and the light receiving element 18 by a lifter (not shown). As shown in FIG. 6, the light path L can be shielded by the remaining ball 1B.

When the remaining ball 1B is detected, the previous work 10 is a defective product having a shortage of the solder ball. Supply the solder balls 1. In FIG. 6, the remaining ball 1B is forcibly dropped into the case 14 and discharged by blowing air from the suction hole 25 of the mounting head 22. Next, the mounting head 22 returns to above the container 2, and the above-described operation is repeated.

(Embodiment 2) FIG. 8 is a side view of a conductive ball mounting apparatus according to Embodiment 2 of the present invention, and FIG. 9 is a light / dark image diagram of the camera. Reference numeral 30 denotes a camera, and 31 denotes a light source for irradiating illumination light upward, and is provided below the moving path of the mounting head 22 in place of the light emitting element 17 and the light receiving element 18. The mounting head 22 picking up the solder balls 1 in the container 2 moves above the camera 30 and is observed by the camera 30. Camera 30 and clamper 1
1, a case 14 ′ as a discharge portion for solder balls
Is provided.

FIG. 9 shows an image obtained by the camera 30. The solder ball 1 is a glossy metal sphere,
When light is emitted from below, only the light that has entered the center is strongly reflected downward and enters the camera 30, so that
Only the center of the solder ball 1 is observed brightly. The lower surface of the mounting head 22 is darkened such as black so that the camera 30 can observe the surface black. In FIG.
1 'is an image of a normal solder ball 1, and 1A' is an image of an extra ball. Therefore, the presence of the extra ball 1A can be easily detected by analyzing this image by a known image processing technique. In addition, this Embodiment 2
Then, the solder balls 1 are vacuum-adsorbed on the lower surface of the mounting head 22 in a total of 25 pieces each of 5 pieces each in a vertical direction.

In the present invention, various design changes are possible, and the detection of the remaining ball 1B shown in FIG. 6 may be performed by the camera 30 shown in FIG. As the conductive balls, gold balls and the like can be used in addition to the solder balls.

[0027]

According to the present invention, the mounting head is moved linearly above the conductive ball supply section, the misball detection section, the misball discharge section, and the work supply section which are arranged on the same straight line. By a simple operation of reciprocally moving, a large number of conductive balls can be mounted on the electrodes of the work with good workability.

[Brief description of the drawings]

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

FIG. 2 is a side view of the conductive ball mounting device according to the first embodiment of the present invention.

FIG. 3 is a plan view of the conductive ball mounting device according to the first embodiment of the present invention.

FIG. 4 is a perspective view of a means for detecting a missed ball in the conductive ball mounting apparatus according to the first embodiment of the present invention;

FIG. 5 is a side view of a means for detecting a missed ball of the conductive ball mounting apparatus according to the first embodiment of the present invention;

FIG. 6 is a side view of a means for detecting a missed ball of the conductive ball mounting apparatus according to the first embodiment of the present invention;

FIG. 7 is an enlarged sectional view of a lower portion of a mounting head of the conductive ball mounting device according to the first embodiment of the present invention.

FIG. 8 is a side view of the conductive ball mounting apparatus according to the second embodiment of the present invention.

FIG. 9 is a light / dark image of a camera of the conductive ball mounting apparatus according to the second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solder ball 1A Extra ball 1B Remaining ball 2 Container 3 Base 4 Brush 10 Work 11 Clamper 14, 14 'Case 17 Light emitting element 18 Light receiving element 22 Mounting head 25 Suction hole 26 Moving table 30 Camera 31 Light source

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-9-92681 (JP, A) JP-A-7-307342 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 23/12 B23P 21/00 305 H01L 21/60

Claims (5)

(57) [Claims] A conductive ball supply section, a missed ball detection means, a remaining ball discharge section detected by the missed ball detection means, and a work positioning section are arranged on the same straight line. , also provided in the supply unit to reciprocate between the positioning portion and moving the provided tables, and the supply unit along the moving table along the positioning portion of the detecting means and the work of the supply unit and misses the ball and the conductive ball disposed mounting head transferring mounted on the workpiece, the miss
The ball detecting means is a light-receiving element and light is directed toward this light-receiving element.
A mounting device for a conductive ball, comprising a light emitting element for irradiating light . 2. A supply section for a conductive ball and a detection section for a miss ball.
Ejection means and the residuals detected by the missed ball detection means.
The ball discharge part and the work positioning part are on the same straight line.
The supply unit and the means for detecting a missed ball
Provide a moving table along the positioning part of the
Along the moving table, between the supply unit and the positioning unit
Reciprocating the conductive ball provided in the supply unit
Conductivity comprising a mounting head for transferring and mounting to the work
Conductive ball mounting method using conductive ball mounting device
The conductive ball provided in the conductive ball supply unit is
Vacuum suction is held in the suction hole opened in the mounting head and held
And mounted on the work positioned on the positioning section.
Later, the mounting head returns to the conductive ball supply section.
The remaining ball is detected by the missed ball detecting means.
Is detected, the remaining ball is dropped and discharged.
Mounting method of conductive balls characterized by discharging to the protrusion
Law. 3. The device according to claim 2, wherein said miss ball detecting means is a light receiving element.
Consisting of a light-emitting element that irradiates light toward a light-receiving element
3. The method according to claim 2, wherein the conductive ball is mounted. 4. An air blower from the suction hole of the mounting head.
The remaining ball to the discharge section
3. The method according to claim 2, wherein the liquid is discharged after being dropped.
Mounting method of conductive balls. 5. A conductive ball is formed by said mounting head.
Before mounting on the workpiece,
Apply the flux in advance using the coating head. And features
4. A method for mounting the conductive ball according to claim 2 or 3.
Law.