JP3319320B2 - 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 a conductive ball mounting apparatus and method for mounting a conductive ball on a work.

[0002]

2. Description of the Related Art As a method for manufacturing electronic components with bumps such as flip chips, a method using a suction head is known. In this method, a conductive ball provided in a supply unit such as a container is vacuum-adsorbed to a suction hole formed in a lower surface of a suction head, picked up, and mounted on an electrode of a work such as a chip. Although a large number of electrodes are formed on the work, each electrode has one conductive ball.
It is necessary to mount the conductive balls one by one at the position corresponding to the work electrode on the lower surface of the suction head.
An adsorption hole for adsorbing only individual pieces is formed.

[0003]

However, in the suction hole of the suction head, two or more conductive balls are picked up by vacuum suction due to vacuum leakage of the suction hole or static electricity generated in the conductive ball. In some cases, in this case, two or more conductive balls are mounted on one electrode of the work. As described above, a bumped electronic component manufactured by mounting two or more conductive balls on one electrode is defective and must be discarded. In the present invention, the conductive balls extra-vacuum-sucked in the suction holes of the suction head are referred to as “extra balls”.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a conductive ball mounting apparatus which can prevent an extra ball from being erroneously mounted on a work and can improve the yield of manufacturing electronic components with bumps.

[0005]

According to the first aspect of the present invention,
A conductive ball supply unit, a work positioning unit, a suction head, a suction head up / down moving unit, and a suction head moving table; and the conductive ball of the supply unit is sucked on the lower surface of the suction head. An apparatus for mounting a conductive ball, which is vacuum-adsorbed and picked up in a hole and transferred and mounted on the work, wherein a landing body is provided on a moving path of the suction head and a height of the suction head is detected. Providing height detecting means, prior to mounting the conductive ball vacuum-sucked in the suction hole on the work, the suction head is moved up and down with respect to the landing body to remove the conductive ball. The landing body is landed, and the height of the suction head at this time is detected by the height detecting means, and the presence or absence of the extra ball is determined based on the detection result.

According to a second aspect of the present invention, a conductive ball provided in a conductive ball supply section is vacuum-adsorbed to a suction hole on a lower surface of the suction head and picked up by causing the suction head to perform an up / down operation. Thereafter, the suction head is moved above the landing body, and the suction head is again moved up and down to land the conductive ball on the lower surface of the landing body on the landing body. At this time, the height of the suction head is detected by height detecting means. And the presence or absence of an extra ball is determined based on the detection result. If it is determined that there is no extra ball, the suction head is moved above the work positioned at the positioning portion, and the suction head is vertically moved there. The conductive ball is mounted on the work, and if it is determined that there is an extra ball, the mounting of the conductive ball on the work is stopped. A.

[0007]

According to each aspect of the present invention, prior to mounting a conductive ball vacuum-sucked on a suction hole of a suction head on an electrode of a work, the conductive ball is landed on a landing body. Thus, the presence or absence of the extra ball is determined. If it is determined that there is an extra ball, the mounting of the conductive ball on the electrode of the work is stopped to eliminate the production of the defective electronic component with bumps.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a conductive ball mounting apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the suction head, and FIG. 3 is a partially enlarged cross-sectional view of the suction head.

First, the overall structure of the conductive ball mounting device will be described with reference to FIG. In FIG. 1, reference numeral 1 denotes a conductive ball, which is stored in a large amount in a container 2 as a supply unit. The container 2 is placed on a base 3. Reference numeral 4 denotes a chip as a work, which is positioned by the positioning unit 5. Reference numeral 11 denotes a suction head, which is mounted on the front of the frame 6. The frame 6 is held on a horizontal moving table 7, and when the motor 8 is driven, the moving table 7 is moved.
Move sideways along. Between the base 3 and the positioning part 5, a flux application part 10 composed of a container in which the flux 9 is stored is arranged.

Next, the suction head 11 and its control system will be described with reference to FIG. The suction head 11 includes an upper box 12 and a lower box 13. A block 14 is provided on the upper part of the lower box 13, and sliders 15 are mounted on both sides of the block 14. Vertical guide rails 16 on which the sliders 15 are slidably fitted are provided on the inner surfaces of both sides of the upper box 12. Therefore, the lower box 13 can move up and down with respect to the upper box 12.

Reference numeral 17 denotes a spring connecting the ceiling surface of the upper box 12 and the block 14, and resiliently pushes the block 14 upward. The spring force of the spring 17 is substantially equal to the weight of the block 14 and the lower box 13, and reduces the weight load of the block 14 and the lower box 13. A tube 18 for vacuum suction of the inside of the lower box 13 is connected to a side surface of the lower box 13, and a large number of suction holes 19 for vacuum suction of the conductive balls 1 are formed on a lower surface of the lower box 13. A touch sensor 20 is provided above the block 14 inside the upper box 12. The sensor 20 detects that the conductive ball 1 vacuum-sucked in the suction hole 19 lands on the bottom surface of the flux coating unit 10 as a landing body as described later. A cylinder 21 is provided on the upper surface of the upper box 12, and a rod 22 of the cylinder 21 is connected to the block 14. By this rod 22 projecting,
The conductive ball 1 vacuum-adsorbed into the suction hole 19 is inserted into the chip 4
Press it against the electrode.

Next, means for vertically moving the suction head 11 will be described. A vertical length case 30 is provided on the side of the suction head 11. A vertical feed screw 31 is housed inside the case 30, and a motor 32 for rotating the feed screw 31 is provided on the upper surface thereof. 33
Is an encoder for detecting the rotation amount of the motor 32. A nut 34 is screwed into the feed screw 31.
Is connected to the upper box 12 via a bar 35. A vertical guide rail 36 is provided on a side surface of the case 30, and a slider 37 mounted on a side surface of the upper box 12 is slidably fitted on the guide rail 36. Therefore, when the motor 32 is driven and the feed screw 31 is rotated,
The nut 34 moves up and down along the feed screw 31, and the suction head 11 also moves up and down along the guide rail 36.

Reference numeral 40 denotes a control unit, and the touch detection circuit 4
1, pressure control unit 42, suction unit 43, height detector 4
4. Connected to the motor drive circuit 45. The touch detection circuit 41 detects a change in the distance from the sensor 20 to the upper surface of the block 14, so that the conductive ball 1 on the lower surface of the suction head 11 comes into contact with the bottom surface of the flux coating unit 10, the upper surface of the chip 4, and the like. Detect that The pressure control unit 42 is connected to the pressure source 46 and controls the gas pressure applied to the cylinder 21. The suction unit 43 suctions the inside of the lower box 13 through the tube 18 under vacuum. The height detector 44 detects the height of the suction head 11 based on the rotation amount of the motor 32 when the sensor 20 detects the upper surface of the block 14. The motor drive circuit 45 is a motor 32
Drive.

The conductive ball mounting apparatus has the above-described configuration. Next, the entire operation will be described. In FIG. 1, the suction head 11 moves above the container 2 and moves up and down to pick up the conductive ball 1 by vacuum suction in the suction hole 19. At this time, as described above, the extra ball easily adheres to the lower surface of the suction head 11.

Next, the suction head 11 is mounted on the flux coating unit 1.
Then, the flux 9 is attached to the conductive ball 1 by moving up and down. FIG. 3 shows this operation in an enlarged manner. FIG. 3 shows a case where the left suction head 11 has an extra ball, and FIG. 3 shows a case where the right suction head 11 has no extra ball. In FIG. 3, 1a is an extra ball. The suction head 11 is lowered, and the conductive balls 1 vacuum-sucked in the suction holes 19 are applied to the flux coating unit 10.
The conductive ball 1 is caused to land on the flux 9 by landing on the bottom surface of the conductive ball 1. Note that the bottom surface of the flux application section 10 is flat, and the depth of the flux 9 is adjusted so that the conductive ball 1 can reach a predetermined depth.

The suction head 11 on the left side in FIG.
As shown in the figure, the extra ball 1a is a conductive ball 1
Lower than the suction head 11
Is lowered, the extra ball 1a lands on the bottom surface of the flux application unit 10. When the suction head 11 still performs the lowering operation, only the upper box 12 continues to lower because the lower box 13 is prevented from lowering, and the lower box 13
, The sensor 20 approaches the upper surface of the block 14 and detects the block 14. This detection signal is sent to the touch detection circuit 41, and the control unit 40
To stop driving. The height detector 44 detects the height H1 of the suction head 11 from the rotation amount of the motor 32 at this time.

In the same manner as in the case of the suction head 11 on the right side in FIG. 3, the height H2 of the suction head 11 when the conductive ball 1 lands on the bottom surface of the flux application section 10 is detected. The height H1 is higher than the height H2 by the protrusion of the extra ball 1a. Therefore, the control unit 40 determines the presence or absence of the extra ball 1a from the difference ΔH in height.

As shown by the suction head 11 on the right side in FIG. 3, if it is determined that there is no extra ball 1a and it is normal, the suction head 11 moves above the chip 4 in FIG. The conductive ball 1 is mounted on the electrode on the upper surface of the chip 4. Also, as shown in the suction head 11 on the left side in FIG. 3, when it is determined that the extra ball 1a is present and abnormal, the conductive ball 1 is
Is stopped, the extra ball 1a is removed, and the operation is resumed. Extra ball 1
a may be manually removed by an operator, or the suction head 11 may be moved to a disposal stage (not shown) where a positive pressure is sent into the lower box 13 to remove all the conductive balls 1 from the disposal stage. May be forcibly dropped.

In the above-described embodiment, the flux application section 10 is also used as a landing body. However, the landing body only needs to be on the moving path of the suction head 11, and therefore, for example, It may be installed. However, if the flux application section 10 is also used as a landing body as in the above-described embodiment, the overall structure can be simplified, and the flux application operation and the extra ball detection operation can be performed together, so that the tact time can be reduced. In addition, the bottom surface of the flux application section 10 is formed to be a strict flat surface in order to cause all the conductive balls 1 to reach a flux of a predetermined depth. Therefore, the flux application section 10 is extremely used as a landing body. Are suitable.

[0020]

According to the present invention, it is possible to easily and accurately determine whether or not extra balls are attached to the lower surface of the suction head, thereby improving the production yield of electronic components with bumps.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view of the suction head of the conductive ball mounting apparatus according to one embodiment of the present invention.

FIG. 3 is a partially enlarged cross-sectional view of a suction head of the conductive ball mounting apparatus according to one embodiment of the present invention;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conductive ball 1a Extra ball 2 Container 4 Chip 5 Positioning part 10 Flux application part 11 Suction head 20 Sensor 31 Feed screw 32 Motor 34 Nut 40 Control part 44 Height detector

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/60 H01L 21/60 311 B23P 21/00 303

Claims (2)

(57) [Claims] A conductive ball supply unit; a work positioning unit; a suction head; a suction head up / down moving means; and a suction head moving table. An apparatus for mounting a conductive ball, which is vacuum-sucked to a suction hole on a lower surface of a head to be picked up and transferred and mounted on the work, wherein a landing body is provided on a moving path of the suction head, and Providing height detecting means for detecting a height, and prior to mounting the conductive ball vacuum-sucked in the suction hole on the work, the suction head is moved up and down with respect to the landing body. The conductive ball lands on the landing body, the height of the suction head at this time is detected by the height detecting means, and the presence or absence of the extra ball is determined based on the detection result. Mounting apparatus of the conductive balls to symptoms. 2. The suction head is moved up and down so that the conductive ball provided in the conductive ball supply section is vacuum-sucked into a suction hole on the lower surface of the suction head and picked up. , And the suction head is moved up and down again so that the conductive ball on the lower surface lands on the landing body. The height of the suction head at this time is detected by the height detection means, and the detection result is obtained. The presence or absence of an extra ball is determined based on the above, and if it is determined that there is no extra ball, the suction head is moved above the work positioned on the positioning portion, and the suction head is moved up and down to perform the conductive ball operation. Mounting the conductive ball on the work, and if it is determined that there is an extra ball, stopping the mounting of the conductive ball on the work.