JP2000332043A - Supplying apparatus of conductive balls in conductive ball mounting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide supplying apparatus of solder balls in solder ball mounting apparatus capable of surely mounting necessary number of solder balls on a package. SOLUTION: This supplying apparatus of conductive balls in conductive ball mounting apparatus is provided with a fixed plate 13, a vessel 18 which is connected with a pin 14 which slidably penetrates the fixed plate 13 and is energized downward and accommodates solder balls 2 inside, and a shaker constituted of a cam follower 19 and cams 24a, 24b which cause the vessel 18 to vibrate upward. The vessel 18 is vibrated in the vertical direction with the shaker, so that the solder balls 2 accommodated in the vessel 18 are levitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a BGA (Ball)
Grid Array), CSP (ChipSize)
Package or Chip Scale Pa
The present invention relates to an apparatus for supplying solder balls in a solder ball mounting apparatus for aligning and mounting solder balls in a package using conductive balls (hereinafter, referred to as solder balls) as a connecting material with a mounting substrate, such as a package.

[0002]

2. Description of the Related Art For example, a solder ball mounting device shown in FIG. 8 has been proposed. This solder ball mounting device
A solder ball supply unit A in which a plurality of solder balls 2 stored in a container 1 are floated by blowing up a compressed gas, and a flux for supplying a flux 4 of a predetermined thickness in a flux tank 3. A plurality of suction holes 6a are formed in the same arrangement as the arrangement of the supply section B, the mounting section C for positioning the package 5 on which the solder balls 2 are to be mounted, and the connection terminals on which the solder balls 1 of the package 5 are mounted. An alignment mask 6 connected to a vacuum pump 8 via 7 and a transfer device D for sequentially moving the alignment mask 6 in the order of the ball supply unit A, the flux supply unit B, and the mounting unit C are provided.

[0005] Then, as shown in FIG. 9, a vacuum pressure is supplied to the alignment mask 6 from the vacuum pump 8 through the pipe 7 while the alignment mask 6 is positioned on the ball supply unit A, and the container 1, the compressed gas is blown out from the bottom of the first solder ball 2 to blow up the internal solder balls 2 toward the alignment mask 6 to float the solder balls 2 therein.
The solder ball 2 is adsorbed on the substrate.

When a predetermined number of solder balls 2 are attracted to the alignment mask 6, the transport device D moves the alignment mask 6 above the flux supply unit B as shown in FIG. As shown, the alignment mask 6 is lowered, the lower end of the solder ball 2 adsorbed by the alignment mask 6 is immersed in the flux 4, and the flux 4 is applied to the solder ball 2.

[0005] When the flux 4 is applied to the solder balls 2, as shown in FIG. 12, the transport device D places the alignment mask 6 above the mounting portion C and places the solder balls 2 in the package 5.
Then, the solder ball 2 is pressed against the connection terminal 5a of the package 5 after being moved to face the connection terminal 5a.
At the same time, the vacuum pressure on the alignment mask 6 is cut off, the solder balls 2 are released from the alignment mask 6, and the solder balls 2 are mounted on the package 5. At this time, as shown in FIG. 13, the solder balls 2 are held by the connection terminals 5 a of the package 5 by the adhesive force of the flux 4.

By heating (reflowing) the package 5 holding the solder balls 2, the solder balls 2 are melted to form, for example, 100 to 3000 solder bumps (connection projections) at a time.

[0007]

In the solder ball mounting apparatus as described above, a depression for fitting the solder ball 2 is formed at the tip of the suction hole 6 in order to surely suck the solder ball 2 with the alignment mask 6. Have been.

[0008] If the depth of the recess varies, the height of the lower end of the solder ball attracted to the alignment mask 6 varies, so that when the flux 4 is applied to the solder ball 2, the individual solder ball 2 Flux 4
In some cases, as shown in FIG. 14, when the flux 4 is applied, the solder ball 2 is not immersed in the flux 4 (the flux is not applied).
May occur.

In such a state, as shown in FIG.
When the solder ball 2 is mounted on the connection terminal 5a of the package 5, the solder ball 2 with a small amount of applied flux has a small adhesive strength due to the flux, so that not only the holding state becomes unstable but also the connection after reflow. The connection between the terminal and the solder bump becomes unstable. Further, the solder ball 6 to which the flux is not applied falls on the connection terminal 5a when the solder ball 6 is released from the alignment mask 6, and moves.
The transfer position accuracy of the solder balls from the alignment mask 6 to the package 5 may be reduced, or the solder balls may fall off from the package 5.

When the amount of protrusion of the solder ball 2 from the lower surface of the alignment mask 6 (dimension S in FIG. 14) becomes small, the flux is applied to the alignment mask 6 when the solder ball 6 is applied with flux. It becomes easy to adhere.

If an alignment mask that does not form a depression is used to eliminate these problems, as shown in FIG. 16, a plurality of solder balls 6 are attracted to one suction hole 6a,
Unnecessary solder balls 2 may be supplied in a state sandwiched between the suction holes 6a, which may cause a defect such as a solder bridge after reflow.

[0012] In view of the above circumstances, an object of the present invention is to provide an alignment mask without providing a depression on a solder ball suction surface.
Further, it is an object of the present invention to provide a solder ball supply device in a solder ball mounting device capable of reliably mounting a required number of solder balls on a package without attracting unnecessary solder balls.

[0013]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 of the present application provides a plurality of connection terminals formed on a package in an alignment mask in the same arrangement as the connection terminals. A conductive ball supply device in a conductive ball mounting device that transfers and mounts a plurality of conductive balls adsorbed to a plurality of formed suction holes, and includes a fixing plate and a solder ball therein. A container to be accommodated, guide means for connecting the fixed plate and the container so as to be relatively movable, and a vibration device for vibrating the container upward, wherein the vibration device vertically vibrates the container. The solder balls contained in the container were allowed to float.

[0014] The invention described in claim 2 is the first invention.
In the invention described in (1), a wire mesh is provided above the solder ball receiving position in the container, and the solder balls that are vibrated and floated by the vibrating device and pass through the wire mesh are sucked by the alignment mask. I did it.

Further, the invention according to claim 3 is the invention according to claim 1.
Alternatively, in the invention according to any one of claims 2, a container having a bottom portion formed of a porous sintered body and a compressed gas supply means for blowing a compressed gas into the container through the porous sintered body are provided. The conductive balls are caused to float by the vibrating force of the vibrating device and the compressed gas supplied from the compressed gas supply means.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention. FIG. 1 is a front sectional view of a solder ball supply device, FIG. 2 is a side sectional view of FIG. 1, and FIG. FIG. 2 is a configuration diagram of a vibration device in FIG. 1.

In FIG. 1, reference numeral 11 denotes a base plate. 1
2 is a bracket fixed to the base plate 11. Reference numeral 13 denotes a frame-shaped fixing plate, which is fixed to the bracket 12.

Reference numeral 14 denotes a pin which slidably passes through the fixed plate 13 and is urged downward by a spring 15.
A plate 16 is connected to the pin 14 via a spherical bearing 17. Therefore, the plate 16 is
5 urges the fixing plate 13 in the direction in which it contacts the fixing plate 13.

Reference numeral 18 denotes a container which is fixed to the plate 16,
A plurality of solder balls 2 are housed inside. A cam follower 19 is rotatably supported by a bracket 20 fixed to the bottom surface of the plate 16.

Reference numerals 21 and 22 denote shafts which are rotatably and parallelly supported by the bracket 12 via bearings 23, respectively. Reference numerals 24a, 24b, 24c, and 24d denote cams, which are fixed to the shafts 21 and 22 so that their phases are shifted by 90 degrees, and are in contact with the cam followers 19.

A timing gear 25 is fixed to the shafts 21 and 22, respectively. Reference numeral 26 denotes a timing belt which is stretched between timing gears 25. A motor 27 is fixed to the base plate 11 via a bracket 28 and is coupled to the shaft 21 via a coupling 29.

In such a configuration, with the plurality of solder balls 2 accommodated in the container 18, the motor 27 is operated to vibrate the container 18 via the cams 24 a, 24 b, 24 c, 24 d and the cam follower 19. The vibration can cause the solder balls 2 in the container 18 to float in the container 18.

For example, with a solder ball 2 having a diameter of 0.3 mm, a floating amount of about 3 mm can be obtained when the weight of the vibrated body is 6 kg, the cam lift is 2 mm, and the rotation speed of the motor 27 is 1600 rpm.

As described above, if the suction surface of the alignment mask is set within the floating range of the solder ball 2 and the vacuum suction is performed while the solder ball 2 is floating about 3 mm, the solder is inserted into the suction hole of the alignment mask. The ball 2 can be held by suction.

At this time, as shown in FIG. 16, two solder balls 2 are sucked in one suction hole or are held by a plurality of solder balls 2 sucked in adjacent suction holes. The solder balls 2 held on the alignment mask in a stable state are flipped up by the vibration of the container 18 and are knocked down from the alignment mask by the collision of the floating solder balls 2, so that all the suction holes of the alignment mask are securely inserted. The solder balls 2 can be held.

The floating amount of the solder ball 2 depends on the container 1
8 can be set arbitrarily according to the magnitude and speed of the vibration applied to 8.

FIGS. 4 and 5 show a second embodiment of the present invention. FIG. 4 is a front sectional view of a solder ball supply device, and FIG. 5 is a side sectional view of FIG. .

In the figure, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals. The container 18 for storing the solder balls 2 includes a stocker base 18a for storing the solder balls 2 and a side wall 18b surrounding the storage portion.
And a wire mesh 18c sandwiched between the stocker base 18a and the side wall portion 18b and covering the storage portion from above. The size of the stitch of the wire mesh 18c is larger than the diameter of the solder ball 2.

With such a configuration, as shown in FIG. 4, a container 18 containing a plurality of solder balls 2 is provided.
With the alignment mask 6 positioned above the
When the container 7 is operated and the container 18 is vibrated through the cams 24a, 24b, 24c, 24d and the cam follower 19, the vibration allows the solder balls 2 in the container 18 to float in the container 18.

At this time, when the solder balls 2 stored in the container 18 float by vibration, the density thereof is dispersed when passing through the wire mesh 26, and the probability that the extra solder balls 2 will be attracted to the alignment mask 18 will be described. Can be reduced.

The wire net 18c is connected to the solder ball 2
It is more effective to select an appropriate value according to the diameter of the mask and the suction pitch of the alignment mask 6.

FIGS. 6 and 7 show a third embodiment of the present invention. FIG. 6 is a front sectional view of a solder ball supply device, and FIG. 7 is a side sectional view of FIG. .

4, the same components as those in FIGS. 4 and 5 are denoted by the same reference numerals. The container 18 for storing the solder balls 2 includes a plate 18d fixed to the plate 16 and a plate 18d formed of a porous sintered body.
The bottom plate 18e embedded in the center of the upper surface of the
8e, a stocker base 18a fixed to the plate 18d so as to surround the space above and storing the solder balls 2.
And a side wall 18b surrounding the storage part, and a wire mesh 18c sandwiched between the stocker base 18a and the side wall 18b to cover the storage part.

The bottom plate 18e is provided with the solder ball 2
(For example, when the diameter of the solder ball 2 is 0.3 mm, the diameter is 0.1 to 0.2 mm).
An individually formed porous sintered body can be used.

A hole communicating with the bottom plate 18e is formed in the plate 18d, and a pipe 30 for connecting a compressed gas supply source (not shown) is connected to the hole.

With this configuration, when the compressed gas is supplied from the pipe 30 when the solder ball 2 is attracted by the alignment mask 6, the compressed gas assists the floating of the solder ball 2 and the alignment mask 6 Since the amount of gas interposed in the space between the container and the container 18 increases, and the amount of gas sucked by the alignment mask 6 increases, the solder balls 2 are surely sucked one by one into each suction hole of the alignment mask 6. be able to.

[0037]

As described above, according to the present invention, the required number of solder balls can be reliably sucked without forming a depression on the solder ball sucking surface of the alignment mask and without sucking unnecessary solder balls. It can be mounted on a package.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a solder ball supply device according to the present invention.

FIG. 2 is a side sectional view of FIG.

FIG. 3 is a configuration diagram of a vibration device in FIG. 1;

FIG. 4 is a front sectional view showing a second embodiment of a solder ball supply device according to the present invention.

FIG. 5 is a side sectional view of FIG. 4;

FIG. 6 is a front sectional view showing a third embodiment of a solder ball supply device according to the present invention.

FIG. 7 is a side sectional view of FIG. 6;

FIG. 8 is an overall configuration diagram of a solder ball mounting device.

FIG. 9 is a front view showing a solder ball alignment step in the solder ball mounting step.

FIG. 10 is a front view showing a flux applying step in the solder ball mounting step.

FIG. 11 is a front view showing a flux applying step in the solder ball mounting step.

FIG. 12 is a front view showing a transfer step to a package in a solder ball mounting step.

FIG. 13 is a front view showing a state where solder balls are mounted on a package.

FIG. 14 is a front view showing a problem in a conventional flux application step.

FIG. 15 is a front view showing a problem in a transfer step according to the related art.

FIG. 16 is a front view showing a problem in a conventional solder ball alignment process.

[Explanation of symbols]

11 ... base plate, 12 ... bracket, 13 ... fixed plate, 14 ... pin, 15 ... spring, 16 ... plate,
18 container, 18a stocker base, 18b side wall, 18c wire mesh, 18d plate, 18e bottom plate,
19: cam follower, 21, 22: shaft, 24a,
24b, 24c, 24d ... cam,

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kosuke Inoue 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside of Hitachi, Ltd. Address: Hitachi, Ltd., Production Technology Laboratory (72) Inventor: Takamichi Suzuki 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture, Japan: Hitachi, Ltd.

Claims (3)

[Claims] 1. A method for transferring and mounting a plurality of conductive balls sucked into a plurality of suction holes formed in the same arrangement as the connection terminals on an alignment mask on a plurality of connection terminals formed on a package. A conductive ball supply device in a conductive ball mounting device, comprising: a fixing plate, a container for housing solder balls therein, guide means for connecting the fixing plate and the container so as to be relatively movable, and the container And a vibrating device for vibrating upward, wherein the vibrating device vibrates the container in a vertical direction, so that the solder balls accommodated in the container are floated. Supply device for conductive balls in the device. 2. A metal mesh arranged above a position for accommodating conductive balls in the container, wherein the conductive balls vibrated and floated by the vibrator and passed through the metal mesh are adsorbed by the alignment mask. 2. The method according to claim 1, wherein
3. A conductive ball supply device in the conductive ball mounting device according to claim 1. 3. A container having a bottom portion formed of a porous sintered body,
Compressed gas supply means for blowing a compressed gas into the container through the porous sintered body, provided in the container by the vibrating force of the vibrating device and the compressed gas supplied from the compressed gas supply means. The conductive ball supplying device according to claim 1 or 2, wherein the conductive ball is floated.