JP3341632B2 - Mounting device for 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 mounting apparatus for mounting a conductive ball on a work.

[0002]

2. Description of the Related Art A flip chip or a BGA (Ball G
2. Description of the Related Art As a method for manufacturing an electronic component with a bump such as a lid array, a method using a conductive ball such as a solder ball is known. As a method for transferring the conductive balls to a work such as a chip or a substrate, a method using a suction tool is known.

In this method, conductive balls stored in a container or the like are vacuum-sucked and picked up in a large number of suction holes formed on the lower surface of a suction tool, and the suction tool is moved above a workpiece to move these conductive balls. Since the conductive balls are transferred onto the electrodes of the work, a large number of conductive balls can be collectively transferred to the work, and thus there is an advantage that workability is good.

When a large number of conductive balls are collectively mounted on a work by the above-described method, the load for pressing the suction tool against the surface of the work is appropriately maintained, and
Accurate positioning of the suction tool with respect to the electrode of the work is required. For this reason, conventionally, a conductive ball mounting head having a pressing means capable of controlling a pressing load has been used. As a method of positioning the suction tool and the electrodes of the work, a method of moving the work horizontally relative to the suction tool in the X direction and the Y direction is widely practiced.

[0005]

By the way, in recent years, as the number of conductive balls mounted collectively for improving the productivity has increased, the work tends to become larger and larger.
For this reason, even if the deviation of the positioning angle between the workpiece and the suction tool (the deviation in the horizontal rotation direction) is slight, the positional deviation between the electrode of the workpiece and the conductive ball sucked by the suction tool cannot be ignored. It has become. For this reason, when positioning the suction tool on the work,
A need has arisen to simultaneously perform position correction not only in the Y direction but also in the horizontal rotation direction (θ direction).

However, the conventional conductive ball mounting apparatus has a problem that the position correction is performed only in the X and Y directions.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a conductive ball mounting device capable of correcting the rotational position.

[0008]

According to the present invention, there is provided an apparatus for mounting a conductive ball, comprising: a work positioning section, a conductive ball supply section, a mounting head, and a vertical moving means for vertically moving the mounting head. And a moving means for moving the mounting head relatively between the work positioning section and the conductive ball supply section, wherein the mounting head comprises a main body and a main body. A suction tool provided on the lower portion of the main body so as to be vertically movable and having a suction hole for a conductive ball formed on a lower surface thereof; pressing means provided on the main body for pressing the suction tool downward; Self-weight reducing means for supporting the suction tool and reducing the self-weight of the suction tool, and a bracket which moves up and down by the vertically moving means
When, and a rotating means for rotating the body θ direction is disposed to the bracket.

[0009]

According to the present invention, the mounting head has a rotating means for rotating the main body in the .theta. Direction and a pressing means provided on the main body for pressing the suction tool downward. Thereby, the pressing load is appropriately maintained, the position of the workpiece and the suction tool in the rotation direction is corrected, and the mounting can be accurately performed with the appropriate pressing load.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a conductive ball mounting apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view of a mounting head of the conductive ball mounting apparatus, and FIG. 3 is a flux of the conductive ball mounting apparatus. FIG. 4 is a partial plan view of a work of the conductive ball mounting device, and FIGS. 5, 6, 7, and 8 are diagrams of a solder ball mounting operation of the conductive ball mounting device. FIG.

In FIG. 1, reference numeral 11 denotes a work, which is mounted on a guide rail 13. The guide rail 13
It is a positioning part for clamping and positioning the work 11. A large number of electrodes 12 are formed on the upper surface of the work 11, and the solder balls 1 as conductive balls are mounted on the electrodes 12. Further, marks A and B for position recognition are provided on the upper surface of the work 11. Guide rail 1
A supply part 14 for the solder balls 1 and a container 16 as a storage part for the flux 2 are provided on the sides of the container 3. 17
Is a squeegee for smoothing the liquid level of the flux 2 stored in the container 16. The supply unit 14 is composed of a box, in which the solder balls 1 are stored.

The mounting head 2 is located above the guide rail 13.
0 is provided. The mounting head 20 is mounted on a Z-axis table 50 which is a vertical moving means. Z axis table 5
0 moves in the X direction along the guide shaft 21. Both ends of the guide shaft 21 are connected to a guide shaft 23 via a slider 22, and the guide shaft 21 moves in the Y direction along the guide shaft 23.
That is, the guide shafts 21 and 23 are mounted on the mounting head 2.
It is a moving means for moving 0 in the X direction and the Y direction. A camera 57 is mounted on a side surface of the Z-axis table 50. The camera 57 captures images of the marks A and B provided on the upper surface of the work 11.

Next, the structure of the mounting head 20 will be described with reference to FIG. Reference numeral 30 denotes a box as a main body. The box 30 is bottomless and has a block 31 inside.
Is stored. A box-shaped suction tool 32 is connected to a lower portion of the block 31. The suction tool 32 is connected to a suction unit 36 via a tube 33, and when the suction unit 36 is operated, the solder balls 1 are vacuum-sucked into suction holes 35 formed on a plurality of lower surfaces thereof. In FIG. 2, the side end of the block 31 is pressed against the bottom plate 30a of the box 30 to ensure the parallelism of the lower surface of the suction tool 32 to the horizontal plane.
That is, the bottom plate 30a defines a lower limit of the suction tool 32 and serves as a stopper for setting the lower surface of the suction tool 32 to a horizontal plane. In the present embodiment,
Since both sides of the block 31 are in contact with the stopper, the parallelism of the lower surface of the suction tool 32 can be maintained with good reproducibility.

On the upper surface of the box 30 are two cylinders 3
The block 31 is connected to the lower end of the rod 39. Reference numeral 40 denotes a spring material. The upper end of the spring material 40 is mounted on the ceiling surface of the box 30, and the lower end is connected to the upper surface of the block 31. Spring material 4
Numeral 0 supports the block 31 with its spring force and the suction tool 32
To reduce (preferably offset) its own weight. That is, the spring member 40 is a means for reducing the weight of the suction tool 32. Sliders 41 provided on both sides of block 31
Are vertical rails 42 provided on the inner surface of the box 30.
Is slidably fitted to

The upper surface of the box 30 is connected to a rotating shaft 46 of a θ-axis motor 45. The θ-axis motor 45 is disposed on the upper surface of the L-shaped bracket 43, and the rotating shaft 46 is supported by a bearing 44 inserted into the bracket 43. By driving the θ-axis motor 45, the box 30 rotates around the θ-axis, and moves the suction tool 32 to the work 1
Positioning is performed in the rotation direction with respect to one electrode 12. Therefore, the θ-axis motor 45 is a rotating means for rotating the box 30 as a main body around the θ-axis.

Next, the means for vertically moving the mounting head 20 will be described with reference to FIG. Reference numeral 50 denotes a Z-axis table provided on the side of the bracket 43, in which a vertical ball screw 51 is housed. A nut 52 is screwed into the ball screw 51, and the nut 52 is connected to the bracket 43 via a rod 53. A vertical rail 54 is provided on the side surface of the Z-axis table 50, and a slider 55 provided on the side surface of the bracket 43 is slidably fitted to the rail 54. When the motor 56 is driven to rotate the ball screw 51, the nut 52 moves up and down along the ball screw 51. As a result, the box 30 and the suction tool 32 move up and down.

Reference numeral 60 denotes a controller, which is a suction unit 3
6. Control the motor drive circuit 61, the pressing force control unit 62, and the like. The motor drive circuit 61 controls the motor 56.
The pressing force control unit 62 controls the pressing force of the cylinder 38 by controlling the air pressure supplied from the pressure source 63. That is, the pressure source 63, the pressure control unit 62, and the cylinder 38 serve as pressing means for pressing the crimping tool 32 downward.

This conductive ball mounting device is constructed as described above, and the operation will be described next. In FIG. 1, the mounting head 20 moves above the supply unit 14. Next, when the motor 56 (FIG. 2) is driven, the mounting head 20 is lowered and raised, and the suction holes 3 on the lower surface of the suction tool 32 are moved.
Then, the solder ball 1 is picked up by vacuum suction.

Next, the mounting head 20 moves upward of the container 16. The flux 2 stored in the container 16 is attached to the lower surface of the solder ball 1 by driving the motor 56 to perform an up-down operation. In this case, the lower end 31a of the side end of the block 31 is pressed against the stopper 30a of the main body 30 as shown in FIG.
2 has a completely horizontal surface, so that all the solder balls 1 vacuum-adsorbed in the suction holes 35 are made to immerse the flux 2 at the same depth, and the flux 2 is attached to all the solder balls 1 in the same amount. Can be done.

Next, the mounting head 20 moves upwardly of the work 11, and the camera 57 images the marks A and B on the substrate 11 during the movement. Thereby, the position of the work 11 is recognized, and the mounting head 20 is positioned with respect to the electrode 12 of the work 11. At this time, as shown in FIG. 4, by rotating the main body 30 by driving the θ-axis motor 45, the positional deviation θ in the rotation direction between the suction tool 32 and the electrode 12 on the work 11 is corrected. Thus, even in the case of a large work or a multi-work work, the suction tool can be correctly positioned on the electrode.

When the positioning is completed, the mounting head 2
0 performs the lowering / upward operation to mount the solder ball 1 on the electrode 12 of the work 11. 5 to 8 show the mounting operation of the solder ball 1 in the order of operation. First, FIG.
The mounting head 20 descends toward the work 11 as shown in FIG. This lowering operation is performed by the forward rotation of the motor 56. At this time, as shown in FIG.
Since the lower side end 31a of 1 is lightly pressed against the stopper 30a, the lower surface of the suction tool 32 is a complete horizontal plane.

Next, the solder ball 1 lands on the electrode 12 as shown in FIG. In this case, since the lower surface of the suction tool 32 is a perfect horizontal surface, all the solder balls 1 reliably land on the electrodes 12 of the work 11. The suction tool 32 is moved by the rod 3 of the cylinder 38 by the reaction force of the landing.
9 rises relatively to the box 30 while pushing it upward (see the gap G).

As shown in FIG. 6, the solder ball 1 is
When the solder ball 1 lands on the electrode 12, the downward force due to the forward rotation of the motor 56 does not act as a force for pressing the solder ball 1 against the electrode 12 (when the solder ball 1 lands on the electrode 12, the suction tool 32 stops the stopper 30a). (See the gap G), and the downward force due to the forward rotation of the motor 56 is not transmitted to the suction tool 32).
1 and the own weight of the suction tool 32 are reduced or offset by the upward spring force of the spring material 40, so that the protruding force f applied by the cylinder 38 being operated and the rod 39 projecting downward is generated by soldering. Ball 1 to electrode 12
Is the majority of the pressing force F that presses against the surface.

That is, the cylinder 38 is a pressing means for pressing the solder ball 1 against the electrode 12 with an appropriate pressing force F, and the force of pressing the solder ball 1 against the electrode 12 of the work 11 by the projection output f. Set the
Therefore, by controlling the protrusion output f of the rod of the cylinder 38, the solder ball 1 is applied to the electrode 12 with an appropriate force (that is, an appropriate amount of force that does not cause the solder ball 1 to be stuck in the suction hole 35 or crushed). Can be imposed.

Next, as shown in FIG. 7, the motor 56 is slightly rotated in the reverse direction to move the suction tool 32 to a slight height H.
(About 0.1 to 0.15 mm). Incidentally, the diameter of the solder ball 1 of the present embodiment is about 1 mm.
As a result, the lower surface of the solder ball 1 slightly floats from the electrode 12 by about 0.1 to 0.15 mm as shown in FIG.
An adhesive flux 2 is interposed between the solder ball 1 and the electrode 12. Then, the vacuum suction state of the solder ball 1 is released, and the motor 56 is further rotated in the reverse direction to raise the suction tool 32.
5 and landed on the electrode 12 again and mounted (FIG. 8). In this case, since the solder ball 1 is attached to the electrode 12 by the adhesive force of the flux 2, if the suction tool 32 is raised, the solder ball 1 is securely separated from the suction hole 35 and mounted on the electrode 12.

As described above, when the solder ball 1 is mounted on the work 11, the work 11 is sent out to the next step along the guide rail 13. Next, a new work 11 is sent to the guide rail 13, and the above-described operation is repeated.

The present invention is not limited to the above embodiment. For example, the flux 2 is applied to the electrode 12 of the work 11 by a means such as a dispenser or a screen printer without adhering to the lower surface of the solder ball 1. May be.

[0028]

According to the present invention, the mounting head is provided with a rotating means for rotating the main body in the θ direction and a pressing means provided on the main body for pressing the suction tool downward, so that the pressing load can be reduced. It is possible to correct the position of the work and the suction tool in the rotation direction while keeping the work properly.Therefore, even in the case of a large work or multiple work, the conductive ball sucked by the suction tool can be It can be positioned correctly and mounted with an appropriate pressing load.

[Brief description of the drawings]

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

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

FIG. 3 is an explanatory view of a flux attaching operation of the conductive ball mounting apparatus according to one embodiment of the present invention.

FIG. 4 is a partial plan view of a work of the conductive ball transfer device according to one embodiment of the present invention;

FIG. 5 is an explanatory diagram of a solder ball mounting operation of the conductive ball mounting apparatus according to one embodiment of the present invention;

FIG. 6 is an explanatory diagram of a solder ball mounting operation of the conductive ball mounting apparatus according to one embodiment of the present invention;

FIG. 7 is an explanatory diagram of a solder ball mounting operation of the conductive ball mounting apparatus according to one embodiment of the present invention.

FIG. 8 is an explanatory diagram of a solder ball mounting operation of the conductive ball mounting apparatus according to one embodiment of the present invention;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solder ball 2 Flux 11 Work 12 Electrode 13 Guide rail 14 Solder ball supply part 20 Mounting head 21, 23 Guide shaft 30 Box (body) 30a Bottom plate (Stopper) 32 Suction tool 35 Suction hole 38 Cylinder 40 Spring material 50 Drive case 51 Ball screw 52 Nut 56 Motor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H05K 3/34 B23K 1/00 B65G 47/91 H01L 21/60

Claims (1)

(57) [Claims] 1. A work positioning part, a conductive ball supply part, a mounting head, a vertical movement means for vertically moving the mounting head, and a mounting head which moves the mounting head to the work positioning part and the conductive head. What is claimed is: 1. An apparatus for mounting a conductive ball, comprising: a moving means for relatively moving between supply portions of balls, wherein the mounting head is provided at a lower portion of the main body so as to be vertically movable and has a lower surface thereof. a suction tool for the suction holes of the conductive balls are formed, and a pressing means for pressing the suction tool downward, and its own weight relief means are attached to the body to reduce the weight of the suction tool by supporting the suction tool, the Up
A bracket that moves up and down by the lowering means and this bracket
Rotating means disposed in the slot to rotate the main body in the θ direction ;
Mounting apparatus of the conductive ball, comprising the.