JPH08309523A - Method for mounting metallic ball - Google Patents

Abstract

PURPOSE: To provide a metallic ball mounting method capable of smoothly transferring even a fine metallic ball to an electrode. CONSTITUTION: A metallic ball 19 is mounted on an electrode 4 of a base plate 3 with a step to adhere the metallic ball 19 onto the adhesive face of an adhesive sheet 23 exposed through plural numbers of positioning holes (through-hole) formed on a mask 33, a step to allign the metallic ball 19 to the electrode 4 of the base plate 3, and a step to strip the adhesive sheet from the mask 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal ball mounting method using a metal ball.

[0002]

2. Description of the Related Art In recent years, in order to form a solder precoat or bump on a substrate or an electrode of an electronic component, a method of using a solder ball as a metal ball having a small diameter of 1 mm or less has been implemented. Also,
Similarly, gold balls as metal balls may be mounted on the electrodes.

However, as the circuit structure or the degree of integration of the electronic components themselves is improved, the electrodes are densified and the diameter of the metal balls themselves tends to become smaller. As described above, as the metal balls are miniaturized, the following problems have become remarkable.

That is, as a specific method of transferring the metal balls to the electrodes, a technique is generally used in which a large number of small holes are formed in the suction head and the metal balls are sucked and transferred to the holes.

[0005]

However, according to this technique, as described above, as the metal balls become finer, it becomes necessary to make a further fine hole in the suction head. Here, it is actually very difficult to accurately drill a large number of small holes using a tool such as a drill, and recently, this method cannot cope with the miniaturization of metal balls.

Further, there is a problem that dust or the like is easily sucked into the small holes, which often causes suction errors to deteriorate productivity. Therefore, an object of the present invention is to provide a metal ball mounting method capable of transferring a metal ball without using a suction head that is difficult to process. In addition, the present invention, even if it is a minute metal ball,
An object of the present invention is to provide a method of mounting a metal ball that can be mounted on an electrode with high productivity.

[0007]

A method of mounting a metal ball according to the present invention is a method of mounting a plurality of metal balls on a plurality of electrodes of a substrate or an electronic component. Adhering a metal ball to the adhesive surface of the adhesive sheet exposed from the through hole, aligning the metal ball and the electrode, and mounting the metal ball on this electrode by peeling the adhesive sheet from the mask including.

[0008]

The metal ball positioned in the positioning hole of the mask adheres to the adhesive surface of the adhesive sheet exposed through the positioning hole. The metal ball adhered to the adhesive sheet is aligned with the electrode, and when the adhesive sheet is peeled off from the mask in this state, the metal ball cannot pass through the positioning hole, so it is removed from the adhesive sheet and mounted on the electrode.

[0009]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a front view of a metal ball mounting apparatus according to an embodiment of the present invention. In FIG. 1, 1 is a metal ball supply part for supplying a metal ball (solder ball in this embodiment) in a fluid state, 2 is an electronic component arranged at a position away from the metal ball supply part 1, and 3 is an electronic component 2. Substrates 4 and 4 are electrodes formed on the surface of the substrate 3. Reference numeral 5 is a holder for holding the electronic component 2, and 6 is X for moving the holder 5 in the X direction.
A table 7 is a Y table for moving the X table 6 in the Y direction.

Reference numeral 8 is a feed screw for rotatably supporting the metal ball supply unit 1 and the upper portion of the electronic component 2 and 9
Is a motor for rotating the feed screw 8, and 10 is a feed nut screwed onto the feed screw 8 and connected to the upper part of the moving table 11. Reference numeral 12 is a transfer unit that is supported to be movable up and down with respect to the moving table 11, and 13 is a Z motor that moves the transfer unit 12 up and down.

Next, the metal ball supply unit 1 will be described with reference to FIG. The metal ball supply unit 1 is an outer cylinder 1
4 and an inner cylinder 15 fitted inside the outer cylinder 14. Further, 17 is a lower mesh attached to the lower part of the outer cylinder 14, 18 is an upper mesh attached to the lower end of the inner cylinder 15, and an outlet 16 for blowing out compressed air is provided at the lower end of the outer cylinder 15. It is open. Then, a large number of metal balls 19 are placed on the upper mesh 18, and compressed air is blown out from the blowout port 16, whereby the metal balls 19 are held in a flowing state.
9 can move in the inner cylinder 15 relatively freely when pressure is applied from the outside.

Next, the transfer section 12 will be described with reference to FIGS. As shown in FIG. 3, the transfer section 12
Inside the reel, a pay-out reel 20 and a take-up reel 21
And are rotatably supported, and the take-up reel 21 is given a rotational force by the drive motor M. An adhesive sheet 23 whose lower surface is an adhesive surface is arranged from the delivery reel 20 toward the take-up reel 21. The delivery reel 20 is a tension applying mechanism (not shown).
The tension is applied to the adhesive sheet 23 by applying a force in the direction opposite to the direction of feeding the adhesive sheet 23 to the feeding reel.

Reference numeral 24 is a cylinder fixed in the direction of the center of the transfer section 12, and the tip of the rod 25 of the cylinder is
The base end portions of the first arm 27 and the second arm 28 are the shaft support portions 2.
It is pivotally supported by 6. Also, the first arm 2
7. A first roller 30 and a second roller 31, which are in circumferential contact with the upper surface side (opposite side of the adhesive surface) of the adhesive sheet 23, are pivotally attached to the tip end portion of the second arm 28, respectively. 29
Is a spring provided on the rod 25, the first arm 27, and the second arm 28, and the spring 29 is always the first spring.
A spring force acts in a direction in which the tip ends of the arm 27 and the second arm 28 are closed.

The lower surface of the transfer section 12 is closed by a mask 33. Positioning holes (through holes) 34 are formed in the mask 33 in accordance with the positions of the electrodes 4 on the substrate 3.
The thickness of the mask 33 is smaller than the diameter of the metal ball 19, and the positioning hole 34 has a shape such that the metal ball 19 cannot pass through the positioning hole 34 and only one metal ball 19 is exposed from the positioning hole 34. The shape is such that it can be adhered to the adhesive surface of the sheet 23.

Now, as shown in FIG. 3, the adhesive sheet 23
Is fed in the direction of the arrow, the rod 25 of the cylinder 24 is retracted, and the rod 25 is retracted so that it is positioned above the first roller 30 and the second roller 31. Then, the spring force of the spring 29 causes the first
The arm 27 and the second arm 28 are in the closed state, and
The roller 30 and the second roller 31 are close to each other.
That is, the adhesive sheet 23 extends from the delivery reel 20 to the take-up reel 21 without contacting the mask 33. The mask 3 facing the adhesive surface of the adhesive sheet 23
The upper surface of 3 is coated with a release agent in advance. This allows
As will be described later, when the adhesive sheet 23 is peeled off from the upper surface of the mask 33, a smooth operation can be performed.

When the adhesive sheet 23 is pressed against the mask 33, the cylinder 24 is driven to cause the rod 25 to project. As a result, the first roller 30 and the second roller 3
1 is the mask 33.
Touch the top surface of. Then, when the rod 25 is further projected, the first arm 27 and the second arm 28 are spread apart against the spring force of the spring 29, and as a result, as shown in FIG. The distance between the roller 31 and the roller 31 increases, and the adhesive sheet 23 between the rollers 30 and 31 comes into contact with the upper surface of the mask 33. At this time, as shown in FIG. 5, the positioning hole 34 is located under the adhesive sheet 23.

Each step of the method of mounting the metal balls in this embodiment will be described with reference to FIG.

First, the motor 9 is driven to move the transfer section 12 above the metal ball supply section 1, and the Z motor 13 is driven to lower the transfer section 12 to move the metal ball supply section 1 The transfer part 12 is brought into contact with the metal ball 19 which is in a fluid state inside. As described above with reference to FIG. 5, the rod 25 is projected in advance and the mask 33 is brought into contact with the adhesive sheet 23. Then, as shown in FIG. 6A, among the metal balls 19 in the fluidized state, those in the vicinity of the positioning holes 34 are aligned by the positioning holes 34, and the adhesive sheet 2
Stick to the sticky side of 3.

Next, the Z motor 13 is driven to move the transfer unit 1.
2 is moved up and the motor 9 is driven to move the metal ball 19 adhered to the adhesive sheet 23 together with the transfer section 12 to above the electronic component 2. And the Z motor 13
Is driven to lower the transfer unit 12. As a result, as shown in FIG. 6B, the metal balls 19 are aligned on the electrodes 4. In FIG. 6 (b), 35 is a flux applied to the electrode 4 in advance.

Next, from the state shown in FIG. 5, the rod 25
Is pulled in, and the adhesive sheet 23 is peeled off from the mask 33 as shown by an arrow N in FIG. Here, as described above, since the diameter of the positioning hole 34 is smaller than the diameter of the metal ball 19, the aligned metal ball 19 is aligned with the positioning hole 3 along with the peeled adhesive sheet 23.
It does not pass through the electrode 4 and come off the electrode 4. The metal balls 19 are also attached to the electrodes 4 by the adhesive force of the flux 35.

Then, the Z motor 13 is driven to move the transfer section 12
It is possible to mount the metal ball 19 on the electrode 4 by raising.

After that, the drive motor M is driven to wind the adhesive sheet 23 on the take-up reel 21 so that the unused portion of the adhesive sheet 23 is located above the positioning hole 34. If the adhesive strength of the adhesive sheet 23 is sufficient, the metal ball may be mounted next without winding.

[0024]

According to the method of mounting a metal ball of the present invention, the step of bringing the adhesive sheet into contact with the upper part of the metal ball while aligning the metal ball with the position of the electrode and transferring the metal ball to the adhesive sheet, Since it includes a step of transferring the transferred metal ball onto the electrode and a step of peeling the adhesive sheet from the metal ball on the electrode and leaving the metal ball on the electrode, the metal ball is removed without using the suction tool. It can be mounted on the electrode. Moreover, since there is no fear of adsorption mistakes, the work of mounting the metal balls can be performed with high productivity.

[Brief description of drawings]

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

FIG. 2 is a sectional view of a metal ball supply unit according to an embodiment of the present invention.

FIG. 3 is an operation explanatory diagram of a transfer unit according to an embodiment of the present invention.

FIG. 4 is an operation explanatory diagram of a transfer unit according to an embodiment of the present invention.

FIG. 5 is an operation explanatory diagram of the transfer section according to the embodiment of the present invention.

FIG. 6A is a process explanatory view of a metal ball mounting method according to an embodiment of the present invention. FIG. 6B is a process explanatory view of a metal ball mounting method according to an embodiment of the present invention. Process explanatory drawing of metal ball mounting method in example (d) Process explanatory drawing of metal ball mounting method in one embodiment of the present invention

[Explanation of symbols]

 4 Electrodes 19 Metal Balls 23 Adhesive Sheets 33 Masks 34 Positioning Holes

Claims (2)

[Claims] 1. A method of mounting a metal ball, wherein a plurality of metal balls are mounted on a plurality of electrodes of a substrate or an electronic component, wherein the metal ball is provided on an adhesive surface of an adhesive sheet exposed from a plurality of through holes formed in a mask. And a step of aligning the metal ball with the electrode, and a step of mounting the metal ball on the electrode by peeling the adhesive sheet from the mask. Mounting method. 2. The mounting of the metal ball according to claim 1, wherein the positioning hole has a shape such that the metal ball cannot pass through and only one metal ball is bonded to the adhesive surface of the adhesive sheet. Method.