JP3500255B2 - Mask device and solder transfer device for solder transfer device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mask device of a solder transfer device for mounting solder particles on a substrate.

[0002]

2. Description of the Related Art A ball grid array (BGA: Bal) is used as a method for soldering electronic elements such as LSI to a substrate.
1 Grid Array) method. In the BGA method, granular solder (hereinafter, referred to as solder ball) is sucked by a jig having holes on the bottom surface that have pores connected to the suction device, and suction is stopped on the pad of the substrate coated with flux. Then, the solder balls are naturally dropped on the flux. Then, the flux is melted by heating in this state, and the solder ball is wrapped in the flux to temporarily fix the solder ball to the substrate.

Each solder ball has a mass of several mm.
Since it is g or less, if the jig or the like is charged with static electricity, or if water or the like is present, it will adhere to the jig or the like. In view of this, in Japanese Unexamined Patent Publication No. 08-025035, an ejecting member that can advance and retreat in the depth direction of the alignment holes of the jig and a driving means for the ejecting member are provided to ensure that the solder balls are separated from the jig. There is. Hereinafter, this technique will be described with reference to the drawings.

FIG. 5 is a sectional view of a mask device in a solder transfer device. 1 is the case. Reference numeral 2 denotes an alignment plate, which is fixed to the case 1 so as to cover the concave portion 3 provided in the case 1. Reference numeral 4 denotes a hole having a bottom, which is arranged on the alignment plate 2 so as to correspond to the pad of the substrate p to which the flux b is applied. Reference numeral 5 denotes a hole, the diameter of which is smaller than that of the hole 4, and the hole 4 and the recess 3 are connected to each other. Reference numeral 6 denotes a pin, which is made of metal such as stainless steel and has a diameter smaller than that of the hole 5, and is held by the pin holding plate 7 and movable in the hole 5. Pin holding plate 7
Is connected to the piston rod 9 of the cylinder 8. 1
Reference numeral 0 is an O-ring, which maintains airtightness between the pin holding plate 7 and the side surface of the recess 3. Reference numeral 11 denotes a hole, which is connected to a suction device (not shown). A table 12 is placed on the base 13. Reference numeral 14 denotes a recess, which is provided on the table 12. Reference numeral 15 is a hole, which is connected to a suction device (not shown). Further, x is a solder ball and has a diameter of 0.3 to 0.
It has a diameter of 76 mm and has a diameter according to the work content.

Next, the transfer operation of the solder balls will be described. It should be noted that when a suction device (not shown) is operated, the concave plate 3 is aligned with the alignment plate 2 (hereinafter referred to as the concave plate 3a) and the concave plate 1 is formed.
4 becomes a negative pressure, the solder balls x in all the holes 4, and the flux b on the pads at predetermined positions on the table 12.
The substrates p coated with are adsorbed and held, respectively. First, the alignment plate 2 in the standby position is positioned horizontally so that the holes 4 face the flux b, and then is positioned vertically with a slight gap provided between the solder ball x and the flux b. Next, the negative pressure in the recess 3a is released to atmospheric pressure, and the pin holding plate 7 is subsequently lowered. Then, each pin 6 has a flux b with a force of about 10 to 30 grams per pin until the solder ball x hits the substrate p.
Push into. Then, the solder ball x is held by the adhesive force of the flux b. With the above, since the transfer is completed, the pin holding plate 7 is raised in the reverse order of the above procedure, the aligning plate 2, that is, the case 1 is returned to the standby position, the concave portion 14 is brought to the atmospheric pressure, and the substrate p is sent to the next step. .

By the way, when soldering is performed, finding a portion where the soldering leaks and repairing the portion where the soldering leaks are extremely troublesome. Therefore, it is confirmed that the solder balls x are present in all the holes 4 before the transfer, and that the solder balls x are not present in all the holes 4 after the transfer to prevent the occurrence of work failure. is doing. In this case, since the solder ball x has a small diameter and the alignment plate 2 has several hundred holes 4, the ring plate or the like is illuminated so that the surface of the alignment plate 2 on the hole 4 side has a uniform illuminance,
The bottom surface is photographed using a CCD camera, and the reflected light data is subjected to image processing to confirm the presence or absence of the solder ball x and determine the presence or absence of a work leak.

[0007]

According to the above method,
The solder ball x can be reliably held on the substrate p. However, the diameter of the solder ball x is 0.05 to 0.1.
Since there are variations in mm, there are the following problems.

1. The position of the solder ball x is displaced. That is, since the moving distances of the pins 6 are all the same, the solder balls x having a small diameter are not sufficiently pushed into the flux b. As a result, the force with which the flux b holds the solder ball x becomes small, and the position of the solder ball x may shift during the movement of the substrate p to the next step.

2. The device for judging the suitability of the work result becomes large. That is, the device space for uniformly illuminating the bottom surface of the alignment plate 2 becomes large, and the device cannot be downsized.

The object of the present invention is to solve the above problems,
(EN) Provided is a mask device for a solder transfer device, which can hold a solder ball securely in a flux and can downsize a device for judging suitability of a work result.

[0011]

In order to solve the above-mentioned problems, the invention of claim 1 is directed to an aligning plate having an aligning hole with which a solder grain is engaged, and a depth of the aligning hole arranged in the aligning hole. In a mask device of a solder transfer device provided with a projecting member that can advance and retreat in the vertical direction and a driving means for the projecting member, the projecting member is formed of an optical fiber.

Further, in addition to the invention of claim 1, the invention of claim 3 is characterized in that a detecting means of light is provided in the movement path of the mask device to detect the irradiation light from the optical fiber. To do.

[0013]

1 is a sectional view of a mask device and an aligning device portion according to an embodiment of the present invention, FIG. 2 is a sectional view of a solder coating device, and FIG. 3 is an embodiment of the present invention. In the plan view of the solder transfer device, in each drawing, the same parts as those in FIG. 5 or those having the same functions are designated by the same reference numerals.

In FIG. 1, reference numeral 20 denotes an optical fiber, the diameter of which is smaller than the diameter of the hole 5, and both end faces are polished. The one end is fixed to the pin holding plate 7 so as to protrude from the pin holding plate 7 by a predetermined length. The one end is arranged in the hole 5, and the other end is grouped together on the cylinder 8 side of the pin holding plate 7 and connected to a lighting device (not shown) outside the case 1 having a uniform illuminance. Here, the protrusion length is such that when the pin holding plate 7 is moved to the descending end, the tip of the optical fiber 20 and the substrate p are
Is a length at which the distance between and is equal to the center diameter of the tolerance of the solder ball x. 21 is a Z moving device, which holds the case 1,
It is held by a Y moving device 43 described later.

A storage box 22 stores a large number of solder balls x and is mounted on the base 13. It should be noted that the solder balls x having the optimum diameter are replaced according to the work. Reference numeral 24 denotes a mesh, the size of the mesh is smaller than the solder ball x, and the solder ball x does not drop from the mesh. Reference numeral 25 denotes a recess, which is connected to an air blowing device (not shown).

In FIG. 2, reference numeral 30 denotes a flux tank which accommodates the flux b therein and is rotatable by a driving means (not shown). Reference numeral 31 denotes a squeegee, which is supported by a stand (not shown) such that the end portion 31a is at a predetermined height from the base 13. By rotating the flux tank, the height of the flux b from the base 13 is always kept constant.

In FIG. 3, reference numeral 41 is an X moving device for moving the Y bar 42 in the X direction. 41a is an X movement device 41
Drive motor. Reference numeral 43 is a Y moving device, which is a Y bar 42.
The top can be moved in the Y direction. 43a is a Y moving device 43
Drive motor. 44 is a clamp, which is a Y moving device 4
3, the jaws 44a and 44b can be opened and closed in the Y direction. 45 is a pallet on which a plurality of substrates p are placed. A transport device 46 positions the pallet 45.
46a is a drive motor for the transport device 46. 50-52
Is a line sensor. With the above configuration, the case 1, the alignment plate 2, and the clamp 44 are positioned in the horizontal direction by operating the X moving device 41 and the Y moving device 43, and in the height direction by operating the Z moving device 21. Positioned.

The operation will be described below. An illumination device (not shown) is operated in advance. First, the clamp 44 is opposed to the substrate p on the pallet 45 and then lowered, and the jaws 44a and 44b are operated to hold the substrate p. Next, after raising the clamp 44 holding the substrate p,
Face the table 12. Subsequently, the clamp 44 is lowered and the substrate p is placed on the table 12 at a predetermined position. Then, the suction device is operated to move the substrate p onto the table 1.
Fix to 2.

Next, the aligning plate 2 is opposed to the storage box 22, and the case 1 is lowered. Then, the suction device is operated to make the concave portion 3 have a negative pressure, and an air blowing device (not shown) is operated to send air into the concave portion 25. Then, the blown up solder ball x is adsorbed and held in the hole 4.

Next, the alignment plate 2 is lifted to a predetermined height and then passed over the line sensor 50 to make the flux tank 2
Face 2 At this time, when the line sensor 50 detects the light from the optical fiber 20, that is, when the hole 4 in which the solder ball x is not adsorbed and held is detected, a detection signal is output to a control device (not shown), and the control device (not shown) operates. And the alarm device (not shown) is activated.

Next, the aligning plate 2 is lowered to attach the flux b to the tips of the solder balls x. Next, the alignment plate 2
Is raised to a predetermined height and then passed over the line sensor 51 to face the table 12. At this time, when the line sensor 51 detects the light from the optical fiber 20,
That is, when the hole 4 in which the solder ball x is dropped is detected,
A detection signal is output to a control device (not shown), and the control device (not shown) stops the work and activates an alarm device (not shown).

Next, the alignment plate 2 is lowered until a slight gap is formed between the lower end of the solder ball x and the substrate p. Then, the suction device is stopped to bring the concave portion 3 to the atmospheric pressure, and the holding plate 7 is moved to the lower end. Then, the optical fiber 20 holds the solder ball x on the substrate p at the tip, as shown in FIG. At this time, when the diameter of the solder ball x is larger than the center of the tolerance, it is bent, but it is a deflection within elastic deformation, and plastic deformation such as buckling or bending due to extreme deformation does not occur.

Next, the holding plate 7 and the aligning plate 2 are raised,
The clamp 44 is opposed to the table 12. Continuing,
The clamp 44 is lowered to hold the substrate p. Then, the suction device is stopped to bring the concave portion 14 to the atmospheric pressure, and then the clamp 44 is moved up, so that the aligning plate 2 moves the line sensor 52.
The substrate p is returned to the pallet 45 by passing through a path opposite to. At this time, when the line sensor 52 cannot capture the light from the optical fiber 20, that is, when there is the hole 4 in which the solder ball x exists, a detection signal is output to a control device (not shown), and the control device (not shown) operates. And the alarm device (not shown) is activated. After that, the above operation is repeated.

In the above description, while the solder balls x are held by the aligning plate 2, they are pressed against the flux whose surface is flattened, and the flux b is adhered to the lower surface of the solder balls x. Flux b on the substrate p in advance
May be applied. Further, as shown in FIG. 4, the hole 4 may not be provided.

Further, since the line sensor 52 needs to perform a detecting operation in accordance with each position of the hole 4, CC
It can be used as a D camera. In addition, the line sensors 50, 51
In this case, the detection operation may be performed in accordance with the respective positions of the holes 4, or the alignment plate 2 may be detected as one detection target at the start and end of the facing of the alignment plate 2.

Further, the illuminating device may be arranged in the vicinity of the case 1, or may be arranged at an arbitrary position such that the length of the optical fiber is about 3 m and the optical fiber is drawn out to the base 13 and fixed.

Finally, an example of a procedure for polishing the optical fiber 20 will be described. At the time of polishing, the optical fiber 20 is lengthened by an appropriate length longer than the finishing length and is embedded in the pin holding plate 7, and is hardened with wax having almost the same hardness as that of the optical fiber 20 so as to completely cover from the implantation surface of the holding plate to the tip. . Then, after the wax is hardened to a sufficient hardness, the wax and the optical fiber are polished together to a prescribed size, and then the wax is dissolved and washed.

[0028]

As described above, according to the present invention, an aligning plate having an aligning hole with which a solder grain is engaged, and a projecting member which is arranged in the aligning hole and is movable back and forth in the depth direction of the aligning hole. In the mask device of the solder transfer device including the driving means for the protruding member, since the protruding member is formed of an optical fiber, the solder balls can be reliably held by the flux, and the suitability of the work result is determined. The device for can be compact.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a mask device and an alignment device portion according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a flux coating device according to an embodiment of the present invention.

FIG. 3 is a plan view of the solder transfer device according to the embodiment of the present invention.

FIG. 4 is a diagram illustrating a transfer operation of the present invention.

FIG. 5 is a cross-sectional view of a mask device in a conventional solder transfer device.

[Explanation of symbols]

2 Alignment plate 4 holes 7-pin holding plate 8 cylinders x Solder balls 20 optical fibers 50,51,52 line sensor

Claims (3)

(57) [Claims] 1. An aligning plate having an aligning hole with which a solder grain is engaged, a projecting member disposed in the aligning hole and capable of advancing and retracting in the depth direction of the aligning hole, and a driving means for the projecting member. A mask device for a solder transfer device, wherein the protruding member is formed of an optical fiber. 2. The solder transfer according to claim 1, wherein an illuminating device is provided, one end of the projecting member is connected to the illuminating device, and light is transmitted to the other end. Equipment mask device. 3. A solder transfer device comprising the mask device according to claim 1, wherein light detecting means is provided in a moving path of the mask device to detect irradiation light from an optical fiber.