JP3152147B2 - Die bonding apparatus and its mechanical adjustment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die bonding apparatus for picking up a chip adhered to an adhesive sheet by a collet and transferring and mounting the chip on a substrate, and a method for mechanically adjusting the die bonding apparatus.

[0002]

2. Description of the Related Art In a die bonding apparatus, a chip adhered to an upper surface of an adhesive sheet is pushed up from below by a needle, vacuum-adsorbed by a collet and picked up, and the collet is moved to a position above a lead frame or a printed circuit board. Then, the collet is moved up and down to transfer and mount the chip on the substrate. A cam mechanism driven by a motor is frequently used as a means for vertically moving a collet or a needle.

In order to increase the efficiency of mounting a chip on a substrate, a collet or a needle moves up and down at a high speed. Further, the height control of the up and down movement of the collet and the needle is performed very precisely so that the chip pickup error and the mounting error on the substrate do not occur. By the way, for example, when the collet is moved up and down to pick up the chip on the adhesive sheet, if the bottom dead center of the collet is too high, the collet cannot reach the upper surface of the chip, so the chip cannot be picked up, and the bottom dead center If it is too low, the collet will hit the top of the chip and destroy it. In addition, if the top dead center of the needle is not appropriate, a similar pickup error occurs. Therefore, prior to the main operation of mounting the chip on the substrate, mechanical adjustment of a device for appropriately setting the bottom dead center of the collet, the top dead center of the needle, and the like is performed.

However, since the normal mounting operation is performed at a high speed, the above-described mechanical adjustment cannot be performed while performing the normal mounting operation. Therefore, conventionally, while the operator manually rotates the handle, the motor is slowly rotated to drive the cam mechanism, thereby performing the mechanical adjustment while moving the collet and the needle up and down at a low speed.

[0005]

The above-mentioned mechanical adjustment is performed when the thickness of the chip changes due to a change in the type of the chip. However, the frequency of this adjustment is quite high, and the operator rotates the handle. However, since it had to be performed manually, there was a problem that a great deal of labor and time were required.

In recent years, a die bonding apparatus has been developed in which a collet up-down operation and a needle up-down operation are performed by separate and independent driving mechanisms. However, in such an apparatus, an accurate operation can be performed manually by an operator. There was a problem that it could not be reproduced.

Accordingly, an object of the present invention is to provide a die bonding apparatus and a method for mechanically adjusting a collet and a needle which can easily and accurately perform mechanical adjustment .

[0008]

SUMMARY OF THE INVENTION The present invention relates to a die bonding apparatus for picking up with a collet while pushing up with a needle from below a chip attached to an upper surface of an adhesive sheet and transferring and mounting the chip on a substrate. Transfer tower
A basic operation pattern storage unit that stores an operation pattern related to the pick-up operation of the collet and the needle in a normal mounting operation to be mounted; and a low-speed operation for machine adjustment created by enlarging the basic operation pattern in the time axis direction. A low-speed operation pattern storage unit for storing a pattern; and a driving unit for driving the collet and the needle to move up and down based on the basic operation pattern and the low-speed operation pattern.

[0009]

According to the above configuration, if a low-speed operation pattern created from a basic operation pattern is stored in advance in a low-speed operation pattern storage unit, the low-speed operation pattern is read out and the low-speed operation is performed on a collet and a needle. , While performing the mechanical adjustment.

Next, an embodiment of the present invention will be described with reference to the drawings. 1 is a configuration diagram of a die bonding apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a pickup method of the chip, FIG. 3 is an explanatory diagram of a pickup operation of the chip, and FIG. FIG. 4B is a basic operation diagram of the chip pickup method, and FIG. 4B is a low-speed operation diagram of the chip pickup method.

First, the overall structure of the die bonding apparatus will be described with reference to FIG. Reference numeral 1 denotes a wafer, and a chip 4 is provided on the surface of the adhesive sheet 3 attached to the ring holder 2.
Are bonded by bond. A push-up unit 6 for chips 4 is provided below the wafer 1.
The push-up unit 6 is configured such that a pepper pot 8 is erected on the upper surface of a case 7 and a needle holder 10 holding a needle 9 is accommodated inside the pepper pot 8.
A first motor 11 is provided on a side of the case 7. The first motor 11 rotates the cam 12. A roller 13 that abuts on the cam 12 is provided below the needle holder 10.
The roller 13 is pressed against the peripheral surface of the cam 12 by the spring force of the spring 14. The cam 12 is a constant velocity cam, and causes the needle 9 to perform a predetermined up-down operation by rotating the cam 12 forward and reverse. That is, the first motor 11, the cam 12, and the roller 13 are first vertical moving means for causing the needle 9 to perform a vertical operation.

A moving table 20 is provided above the wafer 1. The head part 21 is mounted on the moving table 20. The head unit 21 holds a second motor 22, and the second motor 22 holds a collet 23. That is, the second motor 22 is
3 is a second vertical movement means for causing the vertical movement 3 to perform vertical movement. The second motor 22 is a linear motor. Therefore, when the second motor 22 is driven, the collet 23 moves up and down. When the moving table 20 is driven, the head unit 21 moves between the wafer 1 and the substrate 24 in the horizontal direction. 25 is a table for positioning the substrate 24.

Next, the control system will be described. Reference numeral 40 denotes a control unit, which includes a first basic operation pattern storage unit 41A, a first low-speed operation pattern storage unit 41B, and a first pulse generation circuit 4.
2, the first motor 1 via the first motor drive circuit 43
1 is controlled. The control unit 40 also controls the second motor 22 via the second basic operation pattern storage unit 44A, the second low-speed operation pattern storage unit 44B, the second pulse generation circuit 45, and the second motor drive circuit 46. Control the drive. A feedback signal is sent from the first pulse generation circuit 42, the second pulse generation circuit 45, the first motor drive circuit 43, and the second motor drive circuit 46 to the control unit 40.

The first basic operation pattern storage section 41A and the second basic operation pattern storage section 44A store basic operation patterns for causing the needle 9 and the collet 23 to perform predetermined up and down operations, respectively. Further, the first low-speed operation pattern storage unit 41B and the second low-speed operation pattern storage unit 44B are respectively provided in the first basic operation pattern storage unit 4B.
The low-speed operation pattern created by enlarging the basic operation pattern stored in 1A and the second basic operation pattern storage unit 44A in the time axis direction is stored. Here, the basic operation pattern is an operation pattern of a normal mounting operation for transferring and mounting the chip 4 on the adhesive sheet 3 to the substrate 24, and the low-speed operation pattern is a lower dead point of the collet 23 or a needle. 9 is an operation pattern for mechanical adjustment such as setting of the top dead center 9, and this mechanical adjustment is performed prior to the operation of mounting the chip 4 on the substrate 24.

The first pulse generation circuit 42 and the second pulse generation circuit 45 are based on the operation patterns stored in the first basic operation pattern storage section 41A and the second basic operation pattern storage section 44A, respectively. The first motor 11 and the second
To generate a pulse for driving the motor 22 of FIG. 47
Is an input unit for performing various operations. The operator operates this input unit 47 to input, for example, an enlargement magnification of a low-speed operation pattern, and to select which of a basic operation pattern and a low-speed operation pattern is used. I do.

This die bonding apparatus is configured as described above. Next, the overall operation will be described with reference to FIGS. First, as shown in FIG. 1, the collet 23 is stopped above desired chips 4 on the wafer 1. Next, the second motor 22 is driven to lower the collet 23 toward the chip 4. In this case, the collet 23 is shown in FIG.
The collet 23 descends at a high speed from the point b to the point b, descends at a low speed from the point b, and reaches the upper surface of the chip 4 at the point c.
The reason for shifting to the low speed at the point b is to prevent the collet 23 from landing on the chip 4 at a high speed and destroying the chip 4. FIG. 3A shows a state in which the collet 23 has descended to the point b, and FIG. 3B shows a state in which the collet 23 has descended to the point c.

On the other hand, the needle 9 starts rising at point g,
It reaches the lower surface of the adhesive sheet 3 at the point h. FIG. 3C shows the state at this time. That is, the needle 9
After the collet 23 lands on the upper surface of the chip 4, it reaches the lower surface of the adhesive sheet 3 with a slight delay. In step 3,
It is confirmed that the collet 23 and the needle 9 have stopped the lowering operation and the raising operation. This confirmation is performed by the control unit 40 based on feedback signals from the first motor drive circuit 43 and the second motor drive circuit 46. That is, the control unit 40
Is confirmation means for confirming that the lowering operation of the collet 23 and the raising operation of the needle 9 are stopped. After confirming this,
Wait for the stabilization time t to elapse. The stabilization time t is a time required for the collet 23 to firmly suck the chip 4 under vacuum. FIG. 3C shows the needle 9 and the collet 23 during the stabilization time t.

After the stabilization time t has elapsed, the first motor 11 and the second motor 22 are simultaneously driven to drive the needle 9
And the collet 23 are raised synchronously, and the chip 4 is separated from the adhesive sheet 3 and picked up. As a result, the timing at which the collet 23 starts to rise (point d) and the timing at which the needle 9 starts to rise (point i) are surely matched, and the chip 4 is sandwiched between the collet 23 and the needle 9 from above and below to be picked up. can do. FIG.
(D) shows the operation at this time. As shown, the needle 9 breaks through the adhesive sheet 3 and pushes up the chip 4 to peel off the adhesive sheet 3, and the collet 23 raises the pushed up chip 4 while rising. Pick up.

Next, when the needle 9 reaches the point j in FIG. 2, the needle 9 stops rising, starts to descend at the point k, and moves downward toward the point l which is the height of the start position. On the other hand, the collet 23 shifts from the point e to a high speed and stops rising at the point f. FIG. 3E shows a state in the middle. Thus, the pickup operation of the chip 4 by the collet 23 is completed. Next, the moving table 20 starts to be driven, and the collet 23 moves above the substrate 24. The collet 23 moves up and down to transfer the chip 4 to a predetermined position on the substrate 24, and then returns to the start position. Thus, the operation of one cycle is completed. Hereinafter, by repeating the same operation,
The chips 4 of the wafer 1 are mounted on the substrate 24 one after another.

The mounting of the chip 4 on the substrate 24 is performed as described above. The operation shown in FIG. 2 is performed at an extremely high speed (for example, mounting ten chips 4 per second on the substrate 24). . Also, as mentioned in the section on the prior art,
If the height of the bottom dead center of the collet 23, the height of the top dead center of the needle 9, and the operation timing of the collet 23 and the needle 9 are not properly set, a chip 4 pickup error occurs. Therefore, prior to mounting the above-described chip 4, mechanical adjustment of the collet 23 and the needle 9 must be performed.

Hereinafter, mechanical adjustment of the collet 23 and the needle 9 will be described with reference to FIG. FIG. 4A illustrates the basic operation pattern, which is the same as FIG. The basic operation pattern A of the collet 23 is stored in the first basic operation pattern storage section 41A. The basic operation pattern B of the needle 9 is stored in the second basic operation pattern storage section 44A. FIG. 4
FIG. 4B is an enlarged view of the time axis of the basic operation pattern of FIG. 4A. The low-speed operation pattern A ′ is stored in the first low-speed operation pattern storage unit 41B, and the low-speed operation pattern B ′ is It is stored in the second low-speed operation pattern storage section 44B. A'-f 'and g'- of FIG.
l ′ corresponds to a to f and g to l in FIG.

Accordingly, the first motor 11 and the second motor 22 are driven at a low speed in accordance with the low-speed operation patterns A 'and B' shown in FIG.
The operator confirms the setting of the bottom dead center of the collet 23, the setting of the top dead center of the needle 9, etc., and the operation timing while slowly performing the vertical movement. Then, if necessary, mechanical adjustments such as adjustment of the mounting state of the collet 23 and the needle 9 and correction of the basic operation pattern are performed, and driving is performed again at a low speed to confirm the operation. With such a low speed, the operator can perform accurate machine adjustment.

[0023]

According to the present invention, since a low-speed operation pattern can be created more easily than the basic operation pattern, the collet or the needle is moved up and down based on a predetermined low-speed operation pattern while the bottom dead center or Mechanical adjustment such as setting of the top dead center can be easily performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a die bonding apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a chip pickup method according to an embodiment of the present invention.

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

FIG. 4A is a basic operation diagram of a chip pickup method according to an embodiment of the present invention; FIG. 4B is a low-speed operation diagram of a chip pickup method according to an embodiment of the present invention;

[Explanation of symbols]

 Reference Signs List 1 wafer 3 adhesive sheet 4 chip 6 push-up unit 9 needle 11 first motor 20 moving table 22 second motor 23 collet 40 control unit 41A first basic operation pattern storage unit 41B first low-speed operation pattern storage unit 42th No. 1 pulse generation circuit 43 First motor drive circuit 44A Second basic operation pattern storage unit 44B Second low speed operation pattern storage unit 45 Second pulse generation circuit 46 Second motor drive circuit

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Claims (2)

(57) [Claims] 1. A die bonding apparatus for picking up a chip stuck on an upper surface of an adhesive sheet from below with a collet while pushing up with a needle, and transferring and mounting the chip on a substrate. Smell
Low-speed operation of storing that the basic operation pattern storage unit that stores the operation pattern for pickup operation of the collet and the needle, the low-speed operation pattern for mechanical adjustment created by expanding the basic operation pattern in the time axis direction A die bonding apparatus, comprising: a pattern storage unit; and driving means for driving up and down movement of the collet and the needle based on the basic operation pattern and the low-speed operation pattern. 2. A machine for a die bonding apparatus according to claim 1.
Machine adjustment method, based on the low-speed operation pattern
While moving the collet and the needle up and down,
Check the bottom dead center and top dead center of the collet and needle
And a mechanical adjustment method for a die bonding apparatus.