JPH0669285A - Flux supply device - Google Patents

Abstract

(57) [Summary] [Objective] It is an object to provide a means capable of adhering an appropriate amount of soldering flux to a bump of a chip. [Structure] A first storage groove 21 in which the flux 7 is stored on the upper surface of the rotating body 20 and a second storage groove 22 in which the protruding electrode 2 of the chip 1 and the like are deposited to attach the flux are concentrically formed. The first reservoir groove 21 is provided with a fuel raising means 26a for forming the flux 7 stored in the first reservoir groove 21 and supplying it to the second reservoir groove 22.
The squeegee 11 that smoothes the upper surface of the flux 7 stored in the second storage groove 22 is provided in the second storage groove 22. [Effect] The flux 7 is stably supplied from the first reservoir groove 21 to the second reservoir groove 22 little by little, the liquid level of the second reservoir groove 22 is stabilized, and an appropriate amount of the flux 7 is applied to the bump 2. Can be attached.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flux supply device, and more particularly, when mounting a chip on a substrate, a soldering flux is attached to the protruding electrodes protruding from the lower surface of the chip or the lower surfaces of transfer pins. Flux supply device for

[0002]

2. Description of the Related Art Chips provided with protruding electrodes (hereinafter referred to as bumps) are generally called "flip chips", and are advantageous in achieving high density and high integration of substrates.

FIG. 6 shows a conventional device for mounting this type of flip chip (hereinafter simply referred to as "chip") on a substrate. Bumps 2 are provided on the lower surface of the chip 1. The chips 1 are stored in a tray 3 in a matrix form, and are vacuum-sucked by the nozzles 6 of the head 5 which is driven by the moving table 4 and moves in the XY directions, and transferred to a predetermined position.

Below the moving path of the head 5, there is provided a rotating body 101 which is the main body of the flux supplying device.
The flux 7 is stored in a storage groove 102 formed on the upper surface thereof in a ring shape. The flux 7 is discharged from the nozzle 9 of the dispenser 8 and supplied to the reservoir groove 102. A squeegee 11 is arranged in the storage groove 102, and the liquid of the flux 7 stored in the storage groove 102 is driven by the motor 16 provided directly below the rotating body 101 to horizontally rotate the rotating body 101. Smooth the surface. N is the direction of rotation. The rear end of the squeegee 11 is pivotally supported by the pin 12, and the shaft 14 of the micrometer 13 pushes up the squeegee 11 to adjust the height of the lower end of the squeegee 11 submerged in the flux 7. Reference numeral 10 is a substrate on which the chip 1 is mounted, and 17 is a camera for detecting the position of the bump 2.

Next, a method of mounting the chip 1 on the substrate 10 will be described. The head 5 moves above the tray 3 by driving the moving table 4, and the nozzles 6 move up and down there to pick up the chips 1 on the tray 3 by vacuum suction. Next, the head 5 moves above the camera 17,
After the position of the bump 2 is detected by the camera 17, the head 5 moves above the rotating body 101, and the nozzle 6 moves up and down there, so that the bump 2 on the lower surface of the chip 1 lands on the flux 7 (see FIG. The flux 7 adheres to the bump 2 (see the chain line 7).

Next, the head 5 moves above the substrate 10,
Then, the nozzle 1 moves up and down, so that the chip 1 is mounted on the substrate 10 at predetermined coordinate positions. The substrate 10 on which the chip 1 is mounted is sent to a reflow device (not shown), and the bump 1 is heated and melted, so that the chip 1 is soldered to the substrate 10.

[0007]

By the way, in FIG. 7, in order to attach an appropriate amount of the flux 7 to the bump 2, the liquid level of the landing point Q of the bump 2 must be properly controlled. The squeegee 11 is for managing the level of the liquid surface of the flux, and by adjusting the height of the squeegee 11 by the micrometer 13, the level of the liquid surface at the landing point Q on the downstream side of the squeegee 11 is adjusted. Is to be constant. Such management of the liquid level must be strictly performed even in the case of the transfer pin method as disclosed in Japanese Patent Laid-Open No. 2-56944.

However, since the flux 7 has a low viscosity, even if the liquid surface of the squeegee 11 is smoothed, the flux 7 becomes a substream and flows to the downstream side of the squeegee 11 as shown by a broken line arrow R in FIG. The actual liquid level L2 is higher than the predetermined liquid level L1, and as a result, the flux 7 excessively adheres to the lower surfaces of the bumps 2 and the chip 1, and soldering failure is likely to occur. In particular, since the flux 7 is supplied to the reservoir groove 102 by the dispenser 8, the fluctuation of the liquid level is large, and the squeegee 1
The water depth H near the front surface of No. 1 is flux 7 as shown in the figure.
Since the squeegee 11 lifts the tank deeper and makes it considerably deeper, the latent flow also becomes large, and the actual liquid level L2 is likely to be considerably high.

Therefore, it is an object of the present invention to provide a flux supply device capable of depositing an appropriate amount of flux on a bump.

[0010]

According to the present invention, a first reservoir groove and a second reservoir groove in which flux is stored are concentrically formed on the upper surface of a rotating body. Further, the first reservoir groove is provided with a fuel raising means for raising the flux stored in the first reservoir groove and supplying it to the second reservoir groove, and at the same time, the upper surface of the flux stored in the second reservoir groove is removed. A smoothing squeegee is provided in this second reservoir groove.

[0011]

In the above structure, when the motor is driven to rotate the rotating body horizontally, the flux in the first reservoir groove is lifted up by the lifting means and supplied little by little to the second tank. Since the water depth of the flux in the second reservoir is kept shallow and the liquid surface is smoothed by the squeegee, the level of the liquid surface is extremely stable, and the bumps of the chip and the lower surface of the transfer pin are exposed to water. , An appropriate amount of flux can be attached. Further, since the flux is supplied to the first reservoir groove, the liquid level of the liquid varies largely, but the second reservoir groove is supplied with the flux stably with almost no change over time, so that the liquid level of the liquid surface of the second reservoir groove is changed. The fluctuation is extremely small, and an appropriate amount of flux can be attached to the bumps or transfer pins while maintaining a stable liquid level.

[0012]

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

FIG. 1 is an overall perspective view of a chip mounting apparatus, FIG.
FIG. 3 is a sectional view of a flux supply device. The same parts as those of the conventional device are designated by the same reference numerals, and detailed description thereof will be omitted. The rotating body 20 has a disc shape, and a first reservoir groove 21 and a second reservoir groove 22 are formed concentrically on the upper surface thereof. As shown in FIG. 2, the first reservoir groove 21 is deeper than the second reservoir groove 22 to increase the storage capacity of the flux 7. The second reservoir groove 22 is located inside the first reservoir groove 21, and a partition wall 23 thereof has a communication passage 24 formed therein for communicating the reservoir grooves 21 and 22. Second reservoir 2
The liquid level of No. 2 is higher than the liquid level of the first reservoir groove 21, and therefore the flux 7 stored in the second reservoir groove 22 is returned to the first reservoir groove 21 through the communication passage 24. It It should be noted that the communication passage may be any communication passage as long as the flux 7 in the second storage groove 22 can be recirculated to the first storage groove 21, and therefore a slit may be partially formed in the partition wall 23 to form the communication passage. Fine grooves 25 are formed on both sides of the second reservoir groove 22. The narrow groove 25 has a function of preventing the liquid surface of the flux 7 from flowing unnecessarily, and a function of making it easy for excess flux to flow into the communication passage 24.

In FIG. 2, the rotating body 20 is supported by a pedestal 31. Reference numeral 32 is a detent pin. This cradle 3
The shaft 33 hung vertically at 1 is connected to the rotating shaft of the motor 16, and when the motor 16 is driven, the rotating body 20 rotates in the horizontal direction.

A level mechanism 41 is provided below the rotating body 20. The level mechanism 41 adjusts the upper surface of the rotating body 20 to be a horizontal plane, and is screwed to the base plate 42, the horizontal plate 43 provided on the base plate 42, and the base plate 42. The horizontal rod 43 includes a screw rod 44 that pushes up the lower end portion of the horizontal plate 43, and a bearing 45 interposed between the rotating body 20 and the horizontal plate 43. While applying a dial gauge (not shown) to the upper surface of the rotator 20, the screw rod 44 is turned with a fingertip to swing the horizontal plate 43 so that the rotary plate 20 is adjusted to be horizontal.

In FIG. 1, the second reservoir groove 22 is provided with a squeegee 11. The flux 7 is supplied to the first reservoir groove 21 by the dispenser 8. In addition, the first reservoir groove 21 has a lift plate 26 as a lift means.
a is provided. The lift plate 26a is bent and formed at the tip of the hook-shaped arm 26. As shown in FIG. 3, the lift plate 26a is provided with a slight rearward inclination in the rotation direction N, and the outer circumference is more than the outer circumference side so that the flux 7 can be easily lifted to the second reservoir groove 22. The side is thicker. Therefore, when the motor 16 is driven and the rotating body 20 rotates in the N direction, the flux 7 stored in the first storage groove 21 is lifted up by the lift plate 26a and moves over the partition wall 23 as indicated by an arrow K. It flows and is supplied little by little to the second reservoir groove 22.

This apparatus has the above-mentioned structure, and its operation will be described below. In FIG. 1, the head 5 moves above the tray 3 by driving the moving table 4, and the nozzles 6 move up and down there to pick up the chips 1 on the tray 3 by vacuum suction. Next, the head 5 moves above the camera 17, detects the position of the bump 2 by the camera 17, and then moves above the rotating body 20, where the nozzle 6 moves up and down, whereby the bump on the bottom surface of the chip 1 is moved. 2 landed on the flux 7 (see the chain line in Fig. 4), and bump 2
Flux 7 adheres to.

Next, the head 5 moves above the substrate 10,
Then, the nozzle 1 moves up and down, so that the chip 1 is mounted on the substrate 10 at predetermined coordinate positions. The substrate 10 on which the chip 1 is mounted is sent to the reflow device, and the chip 1 is soldered to the substrate 10 by heating and melting the bumps 2.

In the above operation, the flux 7 stored in the first storage groove 21 is lifted up by the lift plate 26, and the second storage groove 2 is stably and little by little changed with time.
Replenished to 2. Therefore, as shown in FIG. 4, the water depth h of the landing point Q of the second reservoir groove 22 is kept shallow, and the water depth H of the front surface of the squeegee 11 is kept shallower than that of the conventional means shown in FIG. The amount of submerged flow R is also extremely small, and the landing point Q
It is possible to adhere a proper amount of flux 7 to the bumps 2 while maintaining the liquid surface level of the above at a predetermined level. Further, since the flux 7 is supplied from the dispenser 8 to the first reservoir groove 22, the liquid level of the flux 7 fluctuates considerably, but the second reservoir groove 21 has a small amount from the first reservoir groove 22. Since only the flux 7 is replenished, the fluctuation of the liquid level is small and the stable liquid level can be maintained.

FIG. 5 shows another method of use. This is one in which the lower surface 51a of the transfer pin 51 is contacted with the flux 7 of the reservoir groove 22 to adhere the flux 7 to the lower surface 51a, and then the flux 7 is transferred to the substrate. Similar effects can be obtained.

The present invention is not limited to the above embodiment, and the flux supply device according to the present invention is mounted on a flip chip as disclosed in, for example, Japanese Patent Application Laid-Open No. 2-56944 previously proposed by the present applicant. It can also be applied to devices. It is also possible to adjust the amount of rise of the flux 7 by changing the inclination angle of the riser plate 26a and the rotation speed of the rotating body 20.

[0022]

As described above, according to the present invention, since the flux is supplied to the first reservoir groove by a dispenser or the like, the liquid level varies greatly, but the second reservoir groove has a secure Since a small amount of flux is stably supplied by the lifting means with almost no change over time, the fluctuation of the liquid surface is small, and it is possible to keep the liquid surface at a stable level and attach an appropriate amount of flux to the bumps of the chip. .

[Brief description of drawings]

FIG. 1 is a perspective view of a chip mounting apparatus according to an embodiment of the present invention.

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

FIG. 3 is a perspective view of a main part of a flux supply device according to an embodiment of the present invention.

FIG. 4 is a developed sectional view of essential parts of a flux supply apparatus according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view of an essential part of another embodiment of the present invention.

FIG. 6 is a perspective view of a conventional chip mounting device.

FIG. 7 is a developed sectional view of essential parts of a conventional flux supply device.

[Explanation of symbols]

 1 Chip 2 Protruding Electrode (Bump) 7 Flux 8 Flux Supply Means (Dispenser) 11 Squeegee 16 Driving Means (Motor) 20 Rotating Body 21 First Reservoir Groove 22 Second Reservoir Groove 26a Lifting Means (Raising Plate)

Claims (1)

[Claims] 1. A first reservoir groove and a second reservoir, each of which comprises a rotating body and a driving means for horizontally rotating the rotating body, and stores flux.
Is formed concentrically on the upper surface of the rotating body, and the flux stored in the first storage groove is raised,
The squeegee is provided in the second reservoir groove, and the squeegee for smoothing the upper surface of the flux stored in the second reservoir groove is provided in the first reservoir groove. Characteristic flux supply device.