JP3172268B2 - Pellet push-up needle setting method and pellet bonding 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 method for setting a pellet pushing needle in a pellet bonding apparatus.

[0002]

2. Description of the Related Art In a pellet bonding apparatus, a semiconductor pellet picked up on a wafer sheet placed in a pellet supply unit is moved downward by a suction collet to suck the pellet or to leave a slight gap between the pellet. Move the push-up needle up from its original position, sandwich the pellet between the suction collet, and simultaneously lift the push-up needle and the suction collet sandwiched with the pellet, separate the pellet from the wafer sheet, and pull the suction collet. Then, the pellet separated from the wafer sheet is transferred by vacuum suction and bonded to the bonding position of the lead frame, and at the same time, the push-up needle is lowered to the original position.

However, in the prior art, when the push-up needle is exchanged by changing the kind of pellets, the tip of the push-up needle is disposed above and in opposition to obtain reproducibility of the mounting position of the push-up needle. The distance z to the position level of the pellet is adjusted each time by a dedicated jig, a gauge, or the like.

[0004]

As described above, in the prior art, the tip of the push-up needle is connected to the dedicated jig as described above,
Since the position is set by using a gauge or the like, a large amount of time is required for the adjustment operation, machine differences between operators are likely to occur, and productivity is impaired.

SUMMARY OF THE INVENTION It is an object of the present invention to easily and accurately recognize the position of the tip of a push-up needle and improve productivity of pellet bonding.

[0006]

According to a first aspect of the present invention, there is provided a pellet push-up needle setting method for setting a push-up position of the push-up needle by a driving device of the pellet push-up needle. When measuring the distance z between the tip and the position level of the semiconductor pellet placed opposite to each other, a. Arrange the suction collet in a state where the semiconductor pellet faces the pellet push-up needle in between,
First, the suction collet is moved in the direction of the semiconductor pellet to hold the semiconductor pellet by suction, and thereafter, the suction collet is moved at a predetermined distance α in the direction of the anti- semiconductor pellet .
A step of stopping only to move, b. Moving the pellet push-up needle in the direction of the semiconductor pellet, and measuring the distance β until the tip reaches the anti-adsorption surface of the semiconductor pellet held by the adsorption collet; c. z = β-α
And obtaining a distance z from the following equation.

[0007] The present invention described in claim 2, serial to claim 1
In the present invention described above, the pellet pushing needle
The position is determined by the distance z determined in claim 1, and
Position of the pellet push-up needle
It is set based on the position. Claim
The present invention described in Item 3 relates to a pellet punch controlled by a control device.
The pushing-up position of the pushing-up needle is determined by the driving device of the rising needle.
Set the pellet bonding equipment
The tip of the push-up needle and the half that is arranged to face the tip
When measuring the distance z from the position level of the conductor pellet
And a. Pair the semiconductor pellet with the needle that pushes up the pellet.
First, place the suction collet facing
The pellet is moved in the direction of the semiconductor pellet to
The suction collet is then held by suction.
In the direction of the let, by a predetermined distance α, b.
Move the pellet push-up needle in the direction of the semiconductor pellet,
A semiconductor pellet whose tip is held by a suction collet
Measuring the distance β until it reaches the anti-adsorption surface of c, c. z
= Computing unit for finding distance z from the equation of β-α
It is like that. The present invention described in claim 4 is a contractor.
In the invention according to claim 3, the control device further comprises:
The arithmetic unit determines the original position of the pellet push-up needle.
Determined by the distance z,
Set the raising position of the raising needle based on the above original position.
That's what I did.

[0008]

After exchanging the push-up needle by switching the kind of pellet, etc., the distance z between the tip of the pellet push-up needle and the position level of the semiconductor pellet disposed opposite to this tip is accurately obtained. The z indicates the position of the tip of the push-up needle after replacement.

[0009]

FIG. 1 is a schematic view showing a procedure for recognizing the position of the tip of a push-up needle in a pellet bonding apparatus. FIG. 2 is a schematic view showing a procedure for picking up a pellet in a pellet bonding apparatus.

A pellet bonding apparatus 10 pushes up a semiconductor pellet 1 adhered on a wafer sheet 2 placed on a pellet supply table (not shown) with a push-up needle 13 driven by a push-up needle driving device 12. Then, the suction collet 15 driven by the collet driving device 14
Thereby, the pushed-up pellet 1 is sucked and transferred, and is bonded to a bonding position of a lead frame (not shown).

The push-up needle driving device 12 presses the push-up needle 13 against a push-up cam 17 by a spring 16 and rotates the cam 17 by a motor 18 to move the push-up needle 13 up and down. A suction cylinder 11 having a suction hole 11 a is provided around the push-up needle 13.
Holds the back surface of the wafer sheet 2 in the vicinity of the pellet 1 pushed up. The control device 100 controls the rotation angle of the cam 17 by controlling the rotation of the motor 18 by the motor drive unit 20 while detecting the rotation amount of the motor 18 by the encoder 19, and controls the pushing amount of the pushing needle 13. I do.

The collet driving device 14 presses the suction collet 15 against a lifting head 22 by a spring 21 and rotates a feed screw 23 screwed to the head 22 by a motor 24 to raise and lower the suction collet 15. . The control device 100 controls the motor 2 by the encoder 25.
The rotation amount of the screw 23 is adjusted by controlling the rotation of the motor 24 by the motor drive unit 26 while detecting the rotation amount of No. 4 to control the amount of elevation of the suction collet 15.

It is needless to say that the above-mentioned motors 18 and 24 can be replaced by linear actuators.

However, in the pellet bonding apparatus 10, the push-up needle 1 is driven by the push-up needle driving device 12.
In setting the push-up position of No. 3, the distance z ″ between the tip of the push-up needle 13 and the position level of the semiconductor pellet 1 disposed opposite to this tip is measured in the arithmetic unit 101 in accordance with the following steps a to c. .

A. Pellet 1 for test on adsorption column 11
Put. Then, the suction collet 15 is arranged above the pellet 1 so as to face the push-up needle 13 (FIG. 1A).
First, the adsorption collet 15 is moved downward to adsorb and hold the pellet 1 (see FIG. 1B), and thereafter, the adsorption collet 15 is raised by a predetermined distance α and stopped (FIG. 1 ( C)).

In FIG. 1B, the lower position of the suction collet 15 for holding the pellet 1 by suction is to electrically detect the timing at which the contact 15A of the suction collet 15 is separated from the contact 22A of the lifting head 22. Is detected by

Further, in FIG. 1 (C), the rising amount α of the suction collet 15 is detected from the detected rotation amount of the encoder 25 during the rising process of the suction collet 15.

B. The push-up needle 13 is raised, and the distance β until the tip reaches the anti-adsorption surface of the pellet 1 held by the adsorption collet 15 is measured (see FIG. 1D).

In FIG. 1D, the push-up needle 13
Is reached when the contact point 15A of the suction collet 15 separates from the contact point 22A of the lifting head 22 due to the rise of the push-up needle 13. Further, the rising amount β of the push-up needle 13
Is the encoder 19 in the process of raising the push-up needle 13.
Is detected from the detected rotation amount.

C. The arithmetic unit 101 calculates α of the above a and b,
Using z, z is obtained from the equation z = β-α.

The pellet 1 is picked up by the pellet bonding apparatus 10 in the following procedures (1) to (5). At this time, the control device 100
01 is set as the original position of the push-up needle 13, and the push-up needle driving device 12 adjusts the push-up amount of the push-up needle 13 as follows.

(1) A wafer sheet 2 on which pellets 1 are adhered is placed on a pellet supply table (not shown) (see FIG. 2A).

(2) After the back surface of the wafer sheet 2 is suction-held by the suction tube 11, the suction collet 15 is moved downward to suction-hold the pellet 1 (see FIG. 2B). The lowering position of the suction collet 15 that holds the pellet 1 by suction is
As described above, the contact is detected by electrically detecting the timing at which the contact 15A of the suction collet 15 separates from the contact 22A of the lifting head 22.

(3) Move the push-up needle 13 from the original position to z + t.
(T is the thickness of the wafer sheet 2), and the pellet 1 is sandwiched between the push-up needle 13 and the suction collet 15 (see FIGS. 2B to 2C).

(4) The push-up needle 13 sandwiching the pellet 1 and the adsorption collet 15 are simultaneously raised by h1 (see FIG. 2 (D)). As a result, the pellet 1 is separated from the wafer sheet 2 that is vacuum-adsorbed on the adsorption cylinder 11.

(5) The suction collet 15 further rises by h2 (see FIG. 2 (E)), transfers the pellet 1 by vacuum suction, and bonds it to the bonding position of the lead frame. At the same time, the push-up needle 13 moves down to the original position.

In the embodiment of the present invention, when z is obtained from the above-mentioned a to c, the wafer sheet 2 is placed on the suction tube 11.
The test pellet 1 is arranged via
May include the thickness t of the wafer sheet 2. In this case, the push-up needle 1 described in (3) above is used.
The amount of increase of 3 becomes z itself including t.

Further, in the above-described embodiment, the type in which the wafer sheet is placed horizontally has been described. However, the present invention can also be applied to a vertical type.

Further, in the embodiment, z obtained by the arithmetic unit 101 is set as the original position of the push-up needle 13, but another position based on this z may be set as the original position.

The operation of this embodiment will be described below.
After exchanging the push-up needle 13 by switching the type of the pellet 1 or the like, the distance z between the tip of the pellet push-up needle 13 and the position level of the pellet 1 disposed opposite to the tip is accurately obtained. This z indicates the tip position of the push-up needle 13 after replacement.

Therefore, the position of the tip of the push-up needle 13 can be easily and accurately recognized, and the push-up needle 1
3 can be adjusted in a short time, and the productivity of pellet bonding can be improved.

[0032]

As described above, according to the present invention, the tip position of the push-up needle can be easily and accurately recognized, and the productivity of pellet bonding can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a procedure for recognizing the position of the tip of a push-up needle in a pellet bonding apparatus.

FIG. 2 is a schematic diagram showing a pellet pickup procedure in a pellet bonding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pellet 11 Suction cylinder 13 Push-up needle 15 Suction collet

Claims (4)

(57) [Claims] 1. A method for setting a push-up needle of a push-up needle by a drive device of the push-up needle, the tip of the push-up needle, and the position level of a semiconductor pellet disposed opposite to the tip. When measuring the distance z of a. The suction collet disposed in a state facing the pellets push-up needle between the semiconductor pellet, firstly moving the suction collet to the semiconductor pellet direction by adsorbing hold the semiconductor pellet, then advance the suction collet counterclockwise semiconductor pellet direction Moving and stopping a predetermined distance α ; b. Moving the pellet push-up needle in the direction of the semiconductor pellet, and measuring the distance β until the tip reaches the anti-adsorption surface of the semiconductor pellet held by the adsorption collet; c. obtaining the distance z from the equation z = β−α. 2. The original position of the pellet push-up needle is requested.
Determined by the distance z obtained in item 1,
The push-up position of the let push-up needle is based on the above original position.
The pellet push-up needle setting according to claim 1, which is set by setting.
Method. (3) Pellet push-up needle controlled by controller
Set the push-up position of the push-up needle with the drive device of
Pellet bonding equipment The tip of the pellet push-up needle and the tip facing
The distance z from the position level of the semiconductor pellet
A. Push up the semiconductor pellet between the pellets
Place the suction collet facing the needle.
The arrival collet is moved in the direction of the semiconductor pellet to
The pellets are held by adsorption, and then the adsorption collet is
Moved a predetermined distance α in the direction of the conductor pellet
B. Move the pellet push-up needle toward the semiconductor pellet.
And the tip is held by the suction collet.
Measure the distance β to reach the anti-adsorption surface of the body pellet
And c. An arithmetic device for calculating the distance z from the equation z = β-α
Pellet bonding equipment characterized by having
Place. (4) The control device is configured to push up the pellet.
The original position of the needle Determined by the distance z obtained by the arithmetic unit
Push-up position of the pellet push-up needle by the driving device
4. The method according to claim 3, wherein the reference position is set based on the original position.
Let bonding equipment.