JPH06140470A - Flip chip bonding device - Google Patents

Abstract

PURPOSE:To provide a device which can efficiently bond a plurality of semiconductor chips having different sized to one substrate by flip chip bonding. CONSTITUTION:This device is provided with a substrate stage 37 which moves and rotates a substrate 15 placed on the stage 37 in the horizontal direction, chip attracting units 35-1, 35-2, and 35-3 which are provided in corresponding to semiconductor chips 11-13 one to one and independently attract and move the chips in the vertical direction, and moving means 34 which fixes and moves the units 35-1, 35-2, and 35-3 in the horizontal direction. In addition, the device is also provided with a first image pickup camera 36-1 which takes the images of the surfaces of the chips attracted to the units 35-1 to 35-3 and inputs picture signals to a controller, second image pickup camera 36-2 which takes and inputs the image of the substrate 15 placed on the state 37, and chip heating unit 38 which bonds one chip to the substrate by flip chip bonding by heating the unit 35-1, 35-2, or 35-3 which brings the chip into contact with the substrate 15 and melting the electrode of the chip.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flip chip bonding apparatus for flip chip bonding (face down bonding) a semiconductor chip on a substrate, and in particular, a plurality of semiconductor chips of different sizes can be efficiently flip chip bonded on one substrate. Flip chip bonding apparatus

The flip chip bonding technique, in which the mechanical connection and the electrical connection between the substrate and the semiconductor chip are performed at the same time, has a merit that the semiconductor chips can be mounted on the substrate at a high density and in a plane. (Fig. 5
reference).

For this reason, the flip chip bonding technique has been rapidly prevailing in recent years despite the disadvantage that the connection state between the substrate and the semiconductor chip cannot be visually confirmed.

From such a background, there is a strong demand for a flip chip bonding apparatus capable of efficiently flip chip bonding semiconductor chips to a substrate, particularly a flip chip bonding apparatus capable of flip chip bonding a plurality of semiconductor chips of different sizes onto one substrate. There is.

Incidentally, FIG. 5 is an explanatory view of a substrate on which a semiconductor chip is mounted, and FIGS. 5 (a) and 5 (b) are schematic side sectional views of the substrate.

[0006]

2. Description of the Related Art Next, a conventional flip chip bonding apparatus will be described with reference to FIG. Figure 6
FIG. 6 (a) is an explanatory view of a conventional flip-chip bonding apparatus, and FIG. 6 (a) is a front view of essential parts schematically showing a state of the apparatus before flip-chip bonding a semiconductor chip to a substrate, and FIG. 6 (b) is a substrate FIG. 4 is a front view of the essential part, which schematically shows the state of the device in which the semiconductor chip is flip-chip bonded.

In FIG. 6, reference numeral 21 denotes a bonding head capable of freely sucking the semiconductor chip 11, 22-1 and 22-2 are connected to the bonding head 21, and the bonding head 21
First and second current cables for heating the current of the bonding head 23, 23 is the bonding head 21 and the first and second current cables 22-1, 22-
Elevating shafts for vertically moving 2 and 24, 24-1 and 24-2 are first and second imaging cameras, 25 is an X stage 25a that moves to the left and right of the paper, a Y stage 25b that moves to the front and back of the paper, and a horizontal surface. The substrate mounting stage is composed of a θ stage 25c that rotates inside.

A method for flip-chip bonding (hereinafter referred to as bonding) the semiconductor chip 11 on the substrate 14 as shown in FIG. 5A using such a conventional flip-chip bonding apparatus will be described with reference to FIG. This will be described below.

First, the front surface (lower end) of the bonding head 21 horizontally attracts the back surface of the semiconductor chip 11, and the substrate 14 is horizontally mounted on the uppermost θ stage 25c of the substrate mounting stage 25. The surface of the semiconductor chip 11 adsorbed on the substrate 21 is photographed by the first imaging camera 24-1, and the surface of the substrate 14 mounted on the substrate mounting stage 25 is captured by the second imaging camera 24-2. Take a picture.

The first and second imaging cameras 24-1, 24-2 are
The photographed surfaces of the semiconductor chip 11 and the substrate 14 are converted into image signals and input to a control device (not shown).
After that, the control device moves the bonding head 21 sucking the semiconductor chip 11 via the drive device (not shown) along the path indicated by the arrow R to a position directly above the substrate mounting stage 25 and moves the stage. X stage 25a and Y stage 25b of the substrate mounting stage 25 via a device (not shown)
And the .theta.
Align so that it contacts the pad 14a of the substrate 14.

The fine movements of the X stage 25a, the Y stage 25b and the θ stage 25c of the substrate mounting stage 25 performed by the control device via the stage moving device are caused by the first and second image pickup cameras 24-1, 24-. Needless to say, this is performed based on the above-mentioned image signal input from 2.

Next, the controller lowers the bonding head 21 along with the elevating shaft 23 in the vertical direction as shown by the arrow D via the above-mentioned driving device, and the semiconductor chip 11 attracted to the tip of the bonding head 21. Electrodes
11a is brought into contact with the pad 14a of the substrate 14 mounted on the θ stage 25c of the substrate mounting stage 25.

When the control device turns on the operation of the power supply (not shown) under such a condition, a large current of about several hundred amperes is generated by the first current cable 22-1, the bonding head 21 and the second current cable. By flowing through the path 22-2, the bonding head 21 instantly becomes hot.

Therefore, the temperature of the semiconductor chip 11 attracted to the bonding head 21 also becomes high, the electrode 11a is melted and bonded to the pad 14a of the substrate 14, and the substrate 14 and the semiconductor as shown in FIG. The mechanical connection and the electrical connection with the chip 11 are made at the same time.

[0015]

If the semiconductor chip 11 mounted on the substrate 14 has only one size, the conventional flip chip bonding apparatus described above has no particular problem.

However, as shown in FIG. 5B, when a plurality of semiconductor chips having different sizes, for example, semiconductor chips 11, 12 and 13 are bonded to one substrate 15 by the conventional flip chip bonding, the bonding is performed. It is essential that the tip of the head 21 has a large shape so as to adsorb the largest size semiconductor chip 13 among the semiconductor chips 11, 12, 13.

Therefore, as shown in FIG. 5B, the semiconductor chip 11-3 (the right end in the drawing) is mounted on the substrate 15 on which the semiconductor chips 11-1, 12, 11-2, 13 are already mounted as described above. If a bonding head 21 with a large tip is used, the semiconductor chip 13 adjacent to this semiconductor chip 11-3
There is a risk that the tip of the bonding head 21 comes into contact with the back surface of the semiconductor chip 11-3 and destroys the semiconductor chip 11-3.

Therefore, in the conventional flip chip bonding apparatus, in order to avoid such a risk, a plurality of bonding heads having different tip sizes are prepared in advance, and the bonding heads are exchanged according to the size of the semiconductor chip. It was essential to do.

However, in such a method, there is a problem that it takes time to replace the bonding head and the efficiency of the bonding work is significantly reduced. The present invention has been made to solve such a problem, and an object thereof is to provide a flip chip bonding apparatus capable of efficiently bonding a plurality of semiconductor chips having different sizes to one substrate.

[0020]

As shown in FIG. 1, a plurality of semiconductor chips 11, 1 having different sizes are provided on a substrate 15.
In a flip chip bonding apparatus for flip chip bonding 2, 13, a substrate 15 is horizontally mounted, and a substrate mounting stage 37 for freely moving and rotating the substrate 15 in a horizontal direction and a semiconductor chip 11, Chip adsorption unit 35-1, 35-corresponding to 12, 13 on a one-to-one basis and adsorbing semiconductor chips 11, 12, 13 separately and moving up and down independently in the vertical direction.
2, 35-3 and the chip suction unit 35-1, 35-2, 35-3 are fixed, and the moving means 34 for moving the chip suction unit 35-1, 35-2, 35-3 in the horizontal direction, Chip suction unit 35-1,35-2,35
First, the respective surfaces of the semiconductor chips 11, 12, and 13 adsorbed by the -3 are photographed, and the image signals thereof are input to the control device.
Image pickup means 36-1, second image pickup means 36-2 for picking up an image of the surface of the substrate 15 placed on the substrate placing stage 37 and inputting the image signal to the control device, and the substrate placing stage. A chip suction unit 35 in which any one of the semiconductor chips 11, 12, 13 is brought into contact with the substrate 15 placed on 37
A chip heating unit 38 for heating any one of the chip adsorption units 1, 35-2 and 35-3 to melt the electrodes of the semiconductor chip and flip-chip bonding the semiconductor chip to the substrate 15. Is achieved by a flip chip bonding apparatus.

[0021]

In the flip chip bonding apparatus of the present invention, the semiconductor chips 11, 12 and 13 having different sizes are in a one-to-one correspondence.
Corresponding to the chip suction units 35-1, 35-2, 35-3, for example, the semiconductor chip 11 is the chip suction unit 35-1, the semiconductor chip 12 is the chip suction unit 35-2, the semiconductor chip 13
Is configured to adsorb the chip adsorption unit 35-3, and heating of the semiconductor chips 11, 12, 13 through the chip adsorption units 35-1, 35-2, 35-3 is performed by one chip heating unit 38. It is configured so that

Therefore, even when a plurality of semiconductor chips 11, 12, 13 having different sizes are bonded to one substrate 15, the chip suction units 35-1, 35-1 corresponding to the respective semiconductor chips 11, 12, 13 are attached. 35-2, 35-3, eg semiconductor chip 11
For this purpose, it is only necessary to select the chip suction unit 35-1, and there is no need to replace the chip suction units 35-1, 35-2, 35-3 with each other. Therefore, the flip-chip bonding apparatus of the present invention can be applied to a plurality of semiconductor chips 1 of different sizes.
It is possible to efficiently bond 1, 12, 13 to one substrate 15.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A flip chip bonding apparatus according to an embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a schematic perspective view of a main part of a flip chip bonding apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory view of a chip suction unit, and FIG. 2 (a) is a schematic view of the chip suction unit. 2 is a side view of the main part of the suction head, and FIG. 3 is a sectional view of the main part of the chip heating unit.

In the present specification, the same reference numerals are given to the same parts and the same materials throughout the drawings. In FIG. 1, 31 is a chip mounting table, 32 is a pickup head, 33 is a guide rail, 34 is a slide plate, 35 is a chip suction unit, 36-1 and 36-2 are first and second imaging cameras, and 37 is A substrate mounting stage, 38 is a chip heating unit.

As shown in FIG. 2, the chip suction unit 35
Is a tongue piece 35a ₁ with good heat conductivity, which has an adsorption hole 35a ₂ on the lower surface.
A chip suction head 35a, a U-shaped member 35b connecting the chip suction head 35a, and a motor (not shown) connected to the chip suction head 35a to rotate the U-shaped member 35b in the direction of arrow RL. It is composed of an eccentric cam 35c which moves up and down in the direction of arrow U-D (vertical direction).

Therefore, the semiconductor chip 11 is sucked onto the tongue piece 35a ₁ of the chip suction head 35a of the chip suction unit 35, the chip suction head 35a is lowered as shown by the arrow D, and the electrode 11a of the semiconductor chip 11 is placed on the substrate. 15 pads 15a
To the tip 35a ₁ of this tip suction head 35a.
When the heating head 38a of the chip heating unit 38 heats the semiconductor chip 11, the temperature of the semiconductor chip 11 also rises, the electrode 11a melts and bonds to the pad 15a of the substrate 15, and the substrate 15 and the semiconductor chip as shown in FIG. The mechanical connection and the electrical connection with 11 will be made at the same time.

The chip suction unit 35 in the flip chip bonding apparatus according to the embodiment of the present invention is equipped with a chip suction head 35a (35a-1) as shown in FIG. 2A to suck the semiconductor chip 11. Chip suction unit 35-1,
A chip suction unit 35-2 having a chip suction head 35a (35a-2) for sucking the semiconductor chip 12 and a chip suction head
The chip suction unit 35-3 is provided with 35a (35a-3) for sucking the semiconductor chip 13 (see FIG. 1).

Further, as shown in FIG. 3, the chip heating unit 38 includes a heating head 38a, a current terminal 38b for supplying a current to the heating head 38a, and an elevating part for moving the heating head 38a up and down in the direction of arrow UD (vertical direction). It is composed of 38c and.

Using the flip-chip bonding apparatus of one embodiment of the present invention having the above structure, a method of bonding a semiconductor chip, for example, the semiconductor chip 11 to the substrate 15 as shown in FIG. It will be explained in order.

To bond the semiconductor chip 11 to the substrate 15, first, the substrate 15 is placed on the θ stage 37c of the bonding substrate placing stage 37, and the chip placing table 31 is placed.
The semiconductor chip 11 is set in (see FIG. 1).

The surface of the substrate 15 on the θ stage 25c faces upward, and the surface of the semiconductor chip 11 on the chip mounting table 31 faces upward. Next, a pickup head 32 controlled by a controller (not shown)
However, after adsorbing the surface of the semiconductor chip 11 on the chip mounting table 31 and picking it up, the semiconductor chip 11 is rotated 180 degrees as shown by an arrow A, and the semiconductor chip 11 is rotationally moved upward.

After that, the slide plate 34 controlled by the control device moves along the guide rail 33 extending in the horizontal direction, and a plurality of chip suction units 35 (35-35-35) fixed to the slide plate 34 in a row state. When one chip suction unit 35-1 of 1, 35-2, 35-3) reaches a position directly above the pickup head 32, its movement is temporarily stopped.

Under such a condition, the chip suction unit 35-1
Lowers its suction head 35a (35a-1) and lowers its tongue piece 35a.
After adsorbing the semiconductor chip 11 set on the pickup head 32 to a ₁ , the chip adsorption head 35a (35a-1) together with the semiconductor chip 11 is lifted and returned to its original position.

After that, the slide plate 34 is attached to the semiconductor chip 11
The chip suction unit 35-1 which is sucking the wafer is moved to a position directly above the first imaging camera 36-1, and the surface of the semiconductor chip 11 is moved to the first position.
The image is taken by the image pickup camera 36-1.

The surface of the substrate 15 mounted on the θ stage 37c of the mounting stage 37 during this time is imaged by the second imaging camera 36-2. First and second imaging cameras 36-1,3
6-2 converts the photographed respective surfaces of the semiconductor chip 11 and the substrate 15 into image signals and inputs them to a control device (not shown).

Semiconductor chip by the first imaging camera 36-1
11 Upon completion of imaging the surface, the slide plate 34 is controlled by the control device and starts moving again.
35-1 together with the semiconductor chip 11 on the substrate mounting stage 37 θ
It moves to directly above the substrate 15 placed on the stage 37c.

The control device includes the first and second image pickup cameras 36.
Based on the above-mentioned image signal input from -1,36-2, the X stage 37a, the Y stage 37b and the θ stage 37c of the substrate mounting stage 37 are finely moved so that the electrode 11a of the semiconductor chip 11 is moved to the pad 15a of the substrate 15. Position so that it can be bonded to.

After this, the eccentric cam of the chip suction unit 35
35c is rotated by a motor (not shown) in a predetermined direction by a predetermined angle to lower the tongue piece 35a ₁ together with the U-shaped member 35b, and the electrode 11a of the semiconductor chip 11 is placed on the substrate mounting stage.
The pad 15a of the substrate 15 placed on the 37 is brought into contact.

In such a state, the elevating part 38c of the chip heating unit 38 is actuated, and the heating head 38a is lowered vertically,
Tongue piece 35 of chip suction head 35a of chip suction unit 35
After contacting a ₁ , the control device turns on the operation of the power supply (not shown) to allow a large current to flow to the heating head 38a through the current terminal 38b for a predetermined time to heat the heating head 38a.

The heating head 38 thus heated to a high temperature
a is the semiconductor chip through the tongue piece 35a ₁ of the suction head 35a.
11 electrodes 11a are melted and bonded to the pads 15a on the substrate 15,
Bonding of the semiconductor chip 11 to the substrate 15 is completed.

The semiconductor chip 12 is bonded to the substrate 15 by using the chip suction unit 35-2, and the semiconductor chip 13 is bonded to the substrate 15 by the chip suction unit 35-2.
Of course, if -3 is used, the semiconductor chips 12 and 13 can be bonded to the substrate 15 in the same manner as the semiconductor chip 11 is bonded to the substrate 15.

Further, the substrate heating base 39 shown in FIG. 4 is mounted on the θ stage 37c of the substrate mounting stage 37 of the flip chip bonding apparatus of the above-described embodiment of the present invention, and the substrate 15 is mounted on the substrate heating base 39. It is also possible to place it.

The substrate heating table 39, as shown in FIG.
A substrate heating table main body 39a for placing the substrate 15 thereon and heating the substrate 15 arbitrarily, and a gas passage 39c communicating with the space S on the substrate 15 mounted on the substrate heating table body 39a are connected to the substrate heating table main body 39a. The heat shield cylinder 39b is formed between the outer peripheral surface of 39a and the heat shield cylinder 39b.

Therefore, when the semiconductor chips 11, 12, 13 and the like are bonded to the substrate 15, the substrate 15 can be heated to an arbitrary temperature and the substrate placed on the substrate heating table body 39a from the gas passage 39c. If the inert gas 40 such as nitrogen gas is blown into the space S above the substrate 15, it is possible to prevent the substrate 15 from being affected by oxygen in the air, and the air in the space S above the substrate 15 can be discharged from the gas passage 39c. If you suck, substrate 15
The dust adhering to the can also be removed.

[0046]

As described above, the present invention makes it possible to provide a flip chip bonding apparatus capable of efficiently bonding a plurality of semiconductor chips of different sizes to a substrate.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a main part of a flip chip bonding apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory view of a chip suction unit.

FIG. 3 is a cross-sectional view of a main part of a chip heating unit.

4A and 4B are explanatory views of a substrate heating table, FIG. 4A is a sectional view of a main part side, and FIG. 4B is a plan view of the main part side.

FIG. 5 is an explanatory diagram of a substrate on which a semiconductor chip is mounted.

FIG. 6 is an explanatory diagram of a conventional flip chip bonding apparatus.

[Explanation of symbols]

 11 to 13, semiconductor chips 11a to 13a, electrodes 14,15, substrates 14a and 15a, pads 21, bonding heads 22-1 and 22-2, current cable 23, lifting shaft 24-1, 24-2, first and second imaging cameras 25, substrate mounting stage 25a, X stage 25b, Y stage 25c, θ stage 31, chip mounting table 32, pickup head 33, guide Rail 34, slide plate 35, chip suction unit 35a, chip suction head 35b, U-shaped member 35c, eccentric cams 36-1, 36-2, first and second imaging cameras 37 , The substrate mounting stage 37a, the X stage 37b, the Y stage 37c, the θ stage 38, the chip heating unit 38a, the heating head 38b, the current terminal 38c, the elevating part 39, the substrate heating table 39a, The substrate heating table body 39b, the heat shield cylinder 39c, the gas passage 40 is an inert gas.

Claims (2)

[Claims] 1. A flip-chip bonding apparatus for flip-chip bonding a plurality of semiconductor chips (11, 12, 13) of different sizes on a substrate (15), wherein the substrate (15) is placed horizontally and the substrate (15) Substrate placement stage (37) that can freely move and rotate 15) in the horizontal direction
And a chip suction unit (35-1) that has a one-to-one correspondence with the semiconductor chips (11, 12, 13) and that sucks the semiconductor chips (11, 12, 13) separately and vertically moves up and down independently. , 35-2,35-3)
And, the chip suction unit (35-1, 35-2, 35-3) is fixed, a moving means (34) for moving the chip suction unit (35-1, 35-2, 35-3) in the horizontal direction. And, each surface of the semiconductor chips (11, 12, 13) sucked by the chip suction unit (35-1, 35-2, 35-3) is photographed, and the image signal is input to the control device. First imaging means (36-1) and the substrate (1) mounted on the substrate mounting stage (37)
The second imaging means (36-2) for imaging the surface of 5) and inputting the image signal to the control device, and the substrate (15) mounted on the substrate mounting stage (37) The chip suction unit (35-1, 35-, which is in contact with any one of the semiconductor chips (11, 12, 13)
2, 35-3) includes a chip heating unit (38) for heating any one chip adsorption unit to melt the electrodes of the semiconductor chip and flip-chip bonding the semiconductor chip to the substrate (15). A flip-chip bonding device characterized by comprising: 2. A substrate heating base body (39a) for mounting the substrate (15) and heating the substrate (15) to an arbitrary temperature, and the substrate mounting base body (39a) for mounting the substrate (15). The substrate heating table (39b) including a gas passage (39c) communicating with the space above the substrate (15) and a heat shield tube (39b) formed between the gas passage (39c) and the outer peripheral surface of the substrate heating table body (39a). ) Is the θ stage (37) of the substrate mounting stage (37) of the flip chip bonding apparatus according to claim 1.
c) A flip chip bonding device characterized by being disposed on the top.