JPH03159197A - Bonding device for flip chip - Google Patents

Abstract

PURPOSE:To confirm a good contact state by a checker, to emit a light to a bond to cure it, and to effectively bond a flip chip to a board by pressing the chip to the board by a presser, and effectively adhering a microbump to a land. CONSTITUTION:A chip P on a wafer 20 is lifted, the chip P is chucked by a sucking unit 26, the chip P is inverted upside down, transferred to a stage 12, positional deviation is roughly corrected by a position correcting pawl 34, transferred to a positioning unit 13 of a board 10 by the nozzle 34 of a transfer head 2, and XY tables 13a, 13b to bring the bump B of the chip P into coincidence with a land 60 are operated. The land 60 is previously coated with a bond 16, the chip P is pressed to the board 10 by a presser 45, and the bump B is effectively brought into contact with the land 60. Then, if the contact state of the bump B with the land 60 is good by a checker 42, the bond 16 is emitted with a light to be cured.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a flip chip bonding apparatus, and more particularly to a means for bonding a flip chip having microbumps to a land on a substrate.

(Prior Art) FIG. 6 shows a state in which a flip chip P is bonded to a substrate 100, and FIG.

is a solder bump protruding from the bottom surface of the flip chip P, and this bump B' is landed on a land (electrode) 101 formed on the substrate 100, and then this substrate lOO is sent to a heating furnace for heat treatment. By this, solder bump B
It was designed to melt and harden. This solder bump B' has a lead function for electrically connecting the flip chip P and the land 101, and a fixing function for fixing the flip chip P to the substrate 100.

By the way, in order to meet the demands for high density and high integration,
Since bumps must be made as small as possible to increase their number, a flip chip P having miniaturized bumps B as shown in FIG. 7 has been proposed. The bumps B reduced in size in this manner are generally called microbumps, and are made of Au, AN, etc., and are distinguished from the solder bumps B° described above.

However, although there is no problem with the above-mentioned lead function even if the bumps are miniaturized micro-bumps B, the above-mentioned fixing function is significantly deteriorated, causing the problem that the flip chip P becomes easily detached from the substrate 100.

In order to solve this problem, UV
A method has been proposed in which a photocurable insulating resin such as a resin is applied, a flip chip is transferred onto the resin, and then the resin is irradiated with light to cure it. According to this means, the fixing function is borne by the resin, so the above problem is solved.

(Problem to be Solved by the Invention) By the way, once the photocurable insulating resin is irradiated with light and hardens, its adhesion is extremely strong, so if bonding fails, the flip chip must be removed from the board and reused. Re-bonding is almost impossible. Therefore, the flip chip must be bonded with the microbumps accurately aligned with the lands.

However, it is quite difficult to accurately match miniaturized microbumps to lands, and even if the above matching is accurate, there are variations in the size of microbumps, making it difficult to match microbumps to lands. Reliable contact cannot be made, and the above-mentioned lead function cannot be achieved. These problems have not yet been solved, and therefore, no specific device for bonding a flip chip having microbumps to a substrate has yet been proposed.

Therefore, an object of the present invention is to provide an apparatus that can reliably bond a flip chip having microbumps to a substrate.

(Means for Solving the Problems) For this purpose, the present invention adsorbs a flip chip arranged with the microbumps on the front side in a chip supply section, and turns the flip chip upside down so that the microbumps are on the bottom side. Vertical inverting device and flipchip device that is inverted vertically
A sub-transfer head that suctions and ticks up the 7-plate to the nozzle and transfers it to the positional deviation correction stage, and a bond made of photocurable insulating resin provided in the bond supply section, and a substrate positioned in the positioning section. The bond application head applies the bond to the land, and the flip chip whose positional deviation has been corrected on the stage is adsorbed to the nozzle and ticked up, and the microbumps of this flip chip are aligned with the lands of the substrate on which the bond is applied. a transfer head that transfers the
Flip chip bonding is performed using a pressure device that applies a load to the nozzle of the transfer head to press the microbumps onto the land, and a light irradiation device that irradiates light onto the bond from below the substrate to harden the bond. configuring the device.

(Function) In the above configuration, the flip chip is pressed against the substrate by the pressurizing device to ensure that the microbumps are brought into contact with the lands. After confirming that the contact between the microbump and the land is good using a checker, the bond is irradiated with light to harden it.

(Example) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a front view of a flip chip bonding device, which has three heads: a sub-transfer head 1, a transfer head 2, and a bond coating head 3. 1 to 3 are attached to sliding Fi5 and Fi6.7, respectively. Each of the sliding plates 5 to 7 is connected by a connecting member 4, and is slidable in the lateral direction N along a horizontal guide 9. The sliding plate 7 on the right side is the horizontal rod 5
1. Swing rod 52. Drive unit 8 via vertical rod 53
The three heads 1 to 3 mounted on each of the sliding plates 5 to 7 are connected to the drive unit 8 and reciprocated in the lateral direction N at the same time, and as will be described in detail later, The sub transfer head 1 transfers the flip chip P from the chip supply section 11 onto the stage 12, the Pp placement head 2 transfers the chip P on the stage 12 onto the substrate 10, and the bond application head 3 transfers the flip chip P from the chip supply section 11 onto the substrate 10. 14 bonds 16 are applied to the substrate 10.

Below the three heads 1 to 3, there is a chip supply section 11,
Bond supply unit 1 equipped with a chip P misalignment correction stage 12, a substrate IO positioning unit 13, and a bond plate 15
4 are arranged in parallel at intervals. The bond tray 15 stores a bond 16 made of a photocurable insulating resin such as UV resin. Further, above each of the above-mentioned parts 11 to 14, a pressing lever 54 is provided which is driven by a driving means (not shown) such as a motor or a cam to reciprocate in the vertical direction.

The sub-transfer head 1 and the bond application head 3 are equipped with an elevator 5.
6 are connected, and when the lever 54 rotates downward,
The roller 57 pivoted on the upper end of the elevator 56 is pressed downward, causing the nozzle 31 and bond application pin 33 of each head 1.3 to descend, and when the pressing state is released, the nozzle 31 and the bond application pin 33 are lowered. The pin 33 is raised by the spring force of the spring material 55.

The chip supply unit 11 includes a wafer 20 to which a flip chip P is attached, a gouer ejector 22 equipped with a push-up pin 21 that pushes up the flip chip P, a support plate 18 for the wafer 20, and a support plate 18 for moving the wafer 20 in the XY force direction. XY child table 9 to be moved and chip P up/down reversing device 2
3 is provided. The gouie ejector 22 is a drive unit 7
0 and the pins 21 protrude and retract, thereby pushing up the chips P on the wafer 20.

The vertical reversing device 23 is driven by a motor 24 and rotates 180°.
It is equipped with an arm 25 that rotates intermittently, and this arm 25
Chip adsorption sections 26 and 27 are provided at both ends of the . For chip 7 P, microbump B should be on the front side.
It is attached to the wafer 20, and by adsorbing the chip P on the wafer 20 and rotating the arm 25 intermittently by 180'', the chip P is turned upside down and the bumps B are placed on the lower side. 58 is the wafer 20 This is a camera for observing the chip P above.

The sub-transfer head l picks up the vertically inverted chip P by adsorbing it to its nozzle 31, and transfers and mounts the chip P on the stage 12 by reciprocating in the lateral force direction N as described above. When performing this tick-up or mounting, the lever 54 rotates as described above to raise and lower the nozzle 31. A position correction claw 34 is provided on the stage 12, and this correction claw 34 slides in the XY force direction and presses against the side wall surface of the chip P, thereby roughly correcting the positional deviation of the chip P. This rough correction is performed by the collet type nozzle 32 of the transfer head 2.
This is done in order to land correctly on the chip P and ensure that the chip P can be attracted.

The positioning section 13 of the substrate 10 is arranged on the XY child tables 3a, 1
It consists of 3b. A positioning member 35 is provided upright on the Y table 13b, and the substrate 10 is positioned at the upper end of the positioning member 35. Further, a second X table 36 is disposed on the Y table 13b, and a light irradiation device 40 for irradiating UV light is provided thereon. This light irradiation device 40 irradiates light from below the substrate 10 to harden the bond 16 made of a photocurable insulating resin coated on the substrate 10. This substrate IO is made of a material such as glass that transmits UV light.

30 is a camera attached to the side of the Y table 13b, and as the Y table 13b moves to the right (see the chain line in Figure 1), this camera 30 is attracted to the nozzle 33 of the transfer head 2. Microbump B on the bottom surface of chip P
Observe. 59 is a camera for observing the substrate 10 provided above the positioning part I3. 42 is a checker, and as will be described in detail later, the probe 43 contacts the electrode portion formed on the substrate 10 and checks the microbumps B of the chip P.
and determines whether the contact state of the land is good or bad.

45 is a pressurizing device that is attached to the sliding plate 6 and reciprocates integrally with the transfer head 2, and as shown in FIG. An extending shaft 48 and a connector 49 attached to the tip of the shaft 48 and coupled to the upper end of the nozzle 32.
and a coil spring 50 that urges the nozzle 32 downward. This pressurizing device 45 is operated when the cylinder 46 is OFF.
As a result, the spring force of the spring 50 causes the nozzle 32 to
A load is applied to press the chip P against the substrate 10 (see the chain line in FIG. 2). Further, when the rod 47 of the cylinder 46 protrudes upward, the nozzle 32 rises against the spring force of the spring 50, releasing the pressed state of the tip P (see the solid line in the figure).

FIG. 3 shows a state in which the chip P is mounted on the substrate 10, in which 60 is a land formed on the upper surface of the substrate 10, 61 is a lead portion led out from the land 60, and 62 is the tip of the lead portion 61. This is an electrode part formed in the part. This device has the above-mentioned configuration, and the overall operation will be explained below.

In FIG. 1, the rainbow 1 container 21 rises and pushes up the chip P on the wafer 20, and the suction part 26 suctions the chip P. Next, the arm 25 rotates 180@ to turn the chip P upside down. Next, the nozzle 3I of the sub-transfer head 1 attracts and ticks up this chip P, and transfers it to the stage 12. Next, the position correction claw 34 slides in the XY force directions to roughly correct the positional deviation of the chip P.

Next, the nozzle 32 of the transfer device 2 attracts and ticks up the chip P, and transfers it to the positioning section 13 of the substrate 10. Before mounting this chip P on the substrate 10, the Y table 13b moves to the side, and the camera 30 observes from below the positional deviation of the microbumps B of the chip P attracted to the nozzle 32. Also, prior to this, camera 59
The lands 6o of the substrate 10 have been observed in advance. Therefore, in order to align the bump B of the chip P with the land 60, XY';r-7'/I/13a and 13b are operated. Then, the cylinder 46 of the pressurizing device 45 is turned off,
The nozzle 32 is lowered by the spring force of the spring 50 and the tip P
Land on the board IO, and place micro bump B on land 6.
Push it to 0.

The application pin 3 of the bond application hand 3 is attached to this land 60.
3, the bond 16 is applied in advance, and the micro bumps B are brought into firm contact with the lands 60 by pressing the chins 7''P against the substrate IO using the pressure device 45 as described above.

Next, the probe 43 of the checker 42 comes into contact with the electrode portion 62 at the tip of the lead portion 61 led out from the land 60 (see FIG. 3), detects the current flowing exclusively between the chip P and the land 60, and connects the bump. It is determined whether the contact state between B and the land 60 is good or bad.

Next, if the determination result is good, the light irradiation device 40 is activated to irradiate the bond 16 with light to harden the bond 16. The bond 16 has curing shrinkage characteristics, and therefore, by curing, the micro bump B is bonded to the land 60.
Connect firmly to the

By the way, as shown in FIG. 4, the chip PI.

P2. When bonding P3... close to each other side by side, if all the bonds 16 applied to the substrate 10 are irradiated with light and the entire area Ll is cured, the bond 16 will protrude to the side of the chip P2. The bond 16a that has been hardened by the above steps becomes an obstacle, and it is not possible to bond the next chip P3 close to the previous chip P2. Therefore, the light does not irradiate all of the bonds 16, but only partially irradiates L2,
Do not cure the part of the bond that protrudes to the side.
After the next chip P2 is brought close to the previous chip P1 and bonded, it is irradiated with light to be cured. The light irradiation device 40 moves in the X direction along the length direction of the substrate 10 and uses the second X table 36 to irradiate the bonds 16 of each chip PI, P2, . . . Move on the Y table 13b.

Incidentally, due to variations in dimensions of the flip chip P, the top surface of the chip P may not be a perfectly horizontal surface, and in that case, it is difficult to press the chip P against the substrate 10 with the nozzle 32. Therefore, as shown in FIG. 5, a variation absorbing means 63 made of an elastic material such as an elastic ring is interposed in the middle of the nozzle shaft 64, and if the above-mentioned variation is absorbed by the elasticity of the elastic material 63, the chips P can be reduced. It can be reliably pressed against the substrate 10.

(Effects of the Invention) As explained above, according to the present invention, by pressing the flip chip with the pressurizing device, it is possible to reliably bring the microbumps into contact with the lands of the substrate, and by using the checker, the microbumps can be brought into contact with the lands of the substrate. Since the bond is hardened by irradiating light after determining whether the contact state of the land is good or bad, the yield can be greatly improved.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which FIG. 1 is a front view of a bonding device, FIG. 2 is a front view of a pressurizing device, FIG. 3 is a plan view of a substrate, and a flip chip with a fourth FIG. 7 is a bonding diagram of a flip chip with micro bumps. B... Microbump P... Flip chip 1 ・ 2 ・ 0 1 2 3 4 6 3 1 2 0 2 3 5 Sub-transfer head Transfer head Bond coating head, substrate, chip supply section, positional deviation correction stage・Positioning unit ・Bond supply unit Bond ・Vertical reversal device ・Nozzle of sub-transfer head ・Nozzle of 7 to transfer ・Light irradiation device ・Checker, probe ・Pressure device

Claims (2)

[Claims] (1) A vertical inversion device that adsorbs a flip chip placed with the microbumps on the front side in a chip supply section and flips the flip chip upside down so that the microbumps are on the bottom side, and a flip chip that has been flipped upside down. A sub-transfer head that sucks the material into the nozzle, takes it up, and transfers it to the positional deviation correction stage, and a bond supplying section that transfers the bond made of photocurable insulating resin to the land of the board positioned in the positioning section. A bond application head is used to apply the bond, and the flip chip whose positional deviation has been corrected on the stage is adsorbed to the nozzle and taken up, and the micro bumps of this flip chip are aligned with the lands of the board on which the bond is applied. A transfer head for transferring, a pressure device that applies a load to the nozzle of this transfer head to press the microbumps onto the land, and a light that irradiates the bond from below the substrate to harden the bond. 1. A flip chip bonding device comprising: an irradiation device. (2) An up-and-down inversion device that adsorbs a flip chip placed with the microbumps on the front side in the chip supply section and inverts the flip chip upside down so that the microbumps are on the bottom side, and a flip chip that has been flipped upside down. A sub-transfer head that picks up the substrate by adsorbing it to a nozzle and transfers it onto the positional deviation correction stage, and a bond made of photocurable insulating resin provided in the bond supply section, which is attached to the substrate positioned in the positioning section. The bond application head that applies to the land and the flip chip whose positional deviation has been corrected on the stage described above are taken up by adsorption to the nozzle, and the micro bumps of this flip chip are aligned with the lands of the substrate on which the bond is applied. By bringing a probe into contact with the transfer head to be transferred and the electrode section connected to the land, and detecting the current flowing between the micro bump and the land,
It is equipped with a checker that determines whether the contact between the microbump and the land is good or not, and a light irradiation device that irradiates light onto the bond from below the substrate to harden the bond when the contact is judged to be good. A flip chip bonding device characterized by: