JP3461196B2 - Chip pickup method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a thrust needle to push up a laser diode attached to an adhesive sheet from the side of the adhesive sheet, and push up the laser diode.
Chip pickup for adsorbing de with suction collet
Relates to a method, and more particularly, thrust needle adhesive based on a current flowing between the suction collet and push needle Shi
Chip pick-up to determine whether or not
On-flops method.

[0002]

2. Description of the Related Art Minute semiconductor chips are handled while being attached to an adhesive sheet during transportation. Therefore, when peeling the semiconductor chip from the pressure-sensitive adhesive sheet, a method is adopted in which the semiconductor chip is pushed up from below using a thrust needle and the pushed semiconductor chip is sucked from above using a suction collet. However, when the semiconductor chip is a very fragile chip such as a laser diode, it may be damaged by the impact at the time of pushing up.
For this reason, damage is prevented by managing the impact at the time of pushing up to the minimum. However, for a defective chip that still occurs, a method of removing it from the processing line by visually inspecting for defects or the like in the appearance has been adopted.

[0003]

However, the above-mentioned damages include not only damages such as chips that can be visually observed from the outside, but also damages such as minute cracks occurring inside the chip. Since such damage is a good product in the visual inspection, the defective chip is sent to the next step and processed, and is judged to be defective only in the inspection after the completion of the processing. In other words, since the defective chip is processed, the processing member and the processing time are wasted, resulting in a problem of reduced production efficiency.

[0004] The present invention was been made to solve the above problems, the purpose of that is to damage the laser diode occurs, focuses on the fact push needle is when breaking through the adhesive sheet An object of the present invention is to provide a chip pickup method capable of accurately detecting a damaged laser diode by electrically detecting this breakthrough.

Another object of the present invention is to provide a chip pin which can prevent the laser diode from being destroyed by an electric shock when the breakthrough is electrically detected.
To provide a backup method .

Another object of the present invention is to provide a chip pickup method capable of preventing a large number of defective chips by counting the number of damaged chips when the damaged chips are successively generated. To do.

[0007]

[Means for Solving the Problems] To solve the above problems
The chip pick-up method of the present invention uses a thrust needle to adhere a laser diode attached to an adhesive sheet.
The laser diode pushed up from the side of the sheet
Chip Pickup for adsorbing using a vacuum collet to over de
In the method, applying a voltage between the protrusion needle and the suction collet, based on the current flowing between the protrusion needle and the suction collet to which the voltage is applied,
Whether the thrust needle broke through the adhesive sheet
It is configured to determine whether or not .

The chip pickup method of the present invention is
Perform the application of the voltage when the laser diode is in a state of being sandwiched by said suction collet and the push-up needle, when not performing the application of voltage, the push-up needle and the suction collet to ground level and to < br />

The chip pickup method of the present invention is
When it is continuously detected that the push-up needle breaks through the adhesive sheet, the number of consecutive detections is counted, and when the count result exceeds a preset value, the laser diode pickup To stop .

[0010]

The operation of the invention according to claim 1 will be described below.

The thrust needle breaks through the adhesive sheet.
If you push up the laser diode directly,
Damage to the laser diode . On the other hand, when the thrust needle does not break through the adhesive sheet, the adhesive sheet acts as a cushioning material, so that no damage occurs in the laser diode .

This is because the adhesive sheet is an insulator, so that when the current flows through the suction collet, the laser diode , and the protruding needle, the adhesive sheet is pierced and the laser diode is damaged. Means that it is happening. That is, the laser die is changed by the value of the current flowing between the suction collet to which a voltage is applied and the protruding needle.
Aether damage is indicated. This was because-size tough, based on the current flowing between the suction collet and push needle, Leh
The sticking needle that may cause damage to the diode
Judge whether or not it has broken through.

The operation of the invention described in claim 2 will be described below.

The suction collet and the thrust needle are lasers.
In the state where the diode is not sandwiched, the charge is removed. Then, when the laser diode is sandwiched, a voltage is applied. Therefore, when the suction collet or the thrust needle comes into contact with the laser diode or when the contact is released, the impact current is prevented from flowing. In addition, the charge due to charging is prevented from flowing to the laser diode .

The operation of the invention according to claim 3 will be described below.

For example, when the thrusting force of the thrusting needle is excessive, the pressure-sensitive adhesive sheet is continuously broken by the thrusting. In other words push the needle is a pressure-sensitive adhesive sheet
The continuous detection of the breakthrough means that there is a problem in the process of picking up the laser diode with the suction collet, and the damaged laser
This means that a large amount of iodine can be generated. This was because-size tough is, butt push-up needle is a pressure-sensitive adhesive sheet
In the case of continuously detecting the breakage, the number of times of continuous detection is counted, and when the count result exceeds a preset value, the pickup of the laser diode is stopped .

[0017]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a chip pickup method according to the present invention.
FIG. 3 is a block diagram showing an electrical configuration of an embodiment of a chip adsorption device for realizing the above.

In the figure, the projecting needle 13 is composed of a needle 23 formed of a metal which is a conductive material, and a drive portion 24 for driving the needle 23.
The laser diode attached to the adhesive sheet (hereinafter referred to as
The semiconductor chip is pushed up from the pressure-sensitive adhesive sheet side in order to peel off the "semiconductor chip" in the specification .

The suction collet 12 is a collet 22.
And a drive unit 21 for driving the collet 22, which sucks the semiconductor chip pushed up by the push-up needle 13 from above and moves the sucked semiconductor chip to a predetermined position.

Further, the voltage applying section 15 includes two switches 2
7, 28, a protection circuit 29, a voltage generation circuit 30, and an application control unit 31. Then, when the suction collet 12 and the protruding needle 13 sandwich the semiconductor chip, a voltage of a predetermined value is applied between the suction collet 12 and the protruding needle 13. When no voltage is applied, the suction collet 12 and the thrust needle 13
And are connected to ground level.

Further, the quality judgment unit 14 includes a suction collet 12
Based on the current flowing between the suction needle 13 and the bump needle 13, the quality of the semiconductor chip sucked by the suction collet 12 is determined. That is, by comparing the voltage at the predetermined location of the voltage application unit 15 with the voltage set by the variable resistor 26, whether the current flowing between the suction collet 12 and the thrust needle 13 has exceeded a predetermined value (that is, , Knee up
It is determined whether or not the dollar 13 has broken through the adhesive sheet 1 . And when it exceeds a predetermined value (Adhesive sheet 1
In the case of breaking through) , an instruction to the effect that there is a defect is sent to the stop determination unit 16 and the device control unit 17.

The stop determination unit 16 monitors the output of the quality determination unit 14 and detects when the quality determination unit 14 detects a defect.
(That is, the thrust needle 13 breaks through the adhesive sheet 1.
The counter is updated, and when no defect is detected, the counter is set to the initial value. That is, when the defects are continuously detected, the number of times of continuous detection is counted. When the count result exceeds the preset value, the device control unit 17 is instructed to stop the pickup operation.

The device control section 17 is a block for controlling the operation of the suction collet 12 and the push-up needle 13, the voltage application section 15, and the like for the semiconductor chip pickup. Then, according to the output of the quality determination unit 14, when the semiconductor chip sucked by the suction collet 12 is a non-defective product, the suction collet 12 is controlled so as to move the sucked semiconductor chip to a predetermined position. When the defective semiconductor chip is sucked, the suction collet 12 is controlled so as to remove it from the processing line. When the stop determination unit 16 gives an instruction to stop the operation, a display to that effect is displayed and the pickup operation of the semiconductor chip is stopped.

The switch 2 in the voltage applying section 15
Reference numerals 7 and 28 switch the connection between the suction collet 12 and the thrust needle 13 between the output of the protection circuit 29 and the ground level. Further, the protection circuit 29 limits the current flowing between the suction collet 12 and the protruding needle 13 to a current value within a predetermined range. The voltage generation circuit 30 also generates a voltage having a predetermined value. Further, the application control unit 31 controls the operations of the switches 27 and 28 and the voltage generation circuit 30 in order to operate as the voltage application unit 15.

The vacuum switching section 11 is a block for controlling the operation of the vacuum source, and controls the operation of the suction collet 12 for sucking the semiconductor chip.

FIG. 2 is a flow chart showing the main operation of this embodiment, and FIGS. 3 and 4 are explanatory views showing the state of pickup of a semiconductor chip. The operation of one embodiment of the present invention will be described below with reference to the drawings as necessary.

In the standby state, the switches 27, 28
Each c contact of is connected to the b contact, and the suction collet 1
2 and the thrust needle 13 are connected to the ground level. In this state, the device control unit 17 controls the vacuum switching unit 11 to change the vacuum switching unit 11 as shown in FIG.
The suction source (not shown) of the suction collet 12 is decompressed by the vacuum source 5 (step S11). Next, the drive unit 21
The suction collet 12 is lowered by controlling
As shown in FIG. 3B, the semiconductor chip 2 attached to the adhesive sheet 1 is adsorbed (step S12).

Then, as shown in FIG. 3C, the protrusion needle 13 is raised by controlling the driving portion 24, and the semiconductor chip 2 is sandwiched between the suction collet 12 and the protrusion needle 13 (step S13). Next, in order to promote the peeling of the semiconductor chip 2 from the adhesive sheet 1, the above state is maintained for a certain period (step S14).

In this stop period, the application controller 31
Connects the c contacts of the switches 27 and 28 to the a contacts and applies a voltage between the suction collet 12 and the protruding needle 13 (step S15). The voltage application is started during this stop period because when the voltage is applied in advance, an excessive current flows when the suction collet 12 contacts the semiconductor chip 2, and the excessive current causes damage to the semiconductor chip 2. Because there is a fear. Then, the quality determination unit 14 monitors the current flowing between the suction collet 12 and the thrust needle 13 (step S16).

FIG. 4 shows a state in the stopped state, and FIG. 4 (a) shows a case where the thrusting needle 13 does not break through the adhesive sheet 1. Further, FIG. 2B shows a case where the thrust needle 13 pierces the adhesive sheet 1 and directly pushes up the semiconductor chip 2. In this case, the impact causes damage to the semiconductor chip 2. Further, an electric current flows through the suction collet 12, the semiconductor chip 2, and the protruding needle 13. Therefore, the quality determination unit 14 detects that a current has flown by comparing the set voltage from the variable resistor 26 and the voltage of the a contact of the switch 27, and outputs a signal indicating the detection of a defect.

Device controller 1 to which this defect detection signal is guided
7 controls the vacuum switching unit 11 to stop the suction of the suction collet 12 (step S23). The application controller 3
The connection of the switches 27 and 28 is switched via 1 to discharge the electric charges charged in the suction collet 12 and the thrust needle 13 to the ground level (step S24). Then, the suction collet 12 is raised and the thrust needle 13 is
Is lowered (steps S25, S26). As a result,
The defective semiconductor chip 2 remains on the pressure-sensitive adhesive sheet 1 and is removed from the subsequent processing line.

The stop determination unit 16 to which the defect detection signal is guided updates the value of the counter provided therein (step S27) and determines whether the updated value exceeds a predetermined range. . If the count value exceeds the predetermined value due to continuous defect detection, there is a basic problem in the pickup operation, and it is considered that a large number of defective products may occur, and an instruction to stop the operation is issued to the device control unit. Send to 17. Therefore, the device control unit 17 stops the pickup operation (steps S28 and S29).

On the other hand, when it is determined in step S28 that the count value is within the predetermined range, the stop determination unit 16
Does not send an instruction to stop, assuming that the defect is accidental. Therefore, the device control unit 17 moves the adhesive sheet 1 by a predetermined distance in order to pick up the next semiconductor chip 2 (steps S28 and S22).

On the other hand, the state shown in FIG. 3C (state in which the semiconductor chip 2 is pushed up by the push-up needle 13).
In step S16, if the push-up needle 13 does not break through the adhesive sheet 1 (see FIG. 4A), that is, if the semiconductor chip 2 is not damaged by the push-up needle 13, the operation following step S16. Indicates steps S17 to S22.

That is, in step S17, the stop determination unit 16 sets the counter for counting the number of consecutive times to the initial value, assuming that the continuity of defect detection is interrupted (step S17). Further, the voltage application unit 15 stops the application of the voltage and connects to the ground level in a state where the suction collet 12 and the protruding needle 13 sandwich the semiconductor chip 2 (step S18).

The reason why the voltage application is stopped at the above timing is that if the voltage is still applied, an excessive current flows to the semiconductor chip 2 when the suction collet 12 and the thrust needle 13 separate from the semiconductor chip 2. Fear,
This is because this current may cause damage to the semiconductor chip 2.

Next, the device control unit 17, as shown in FIG. 3D, is a suction collet 12 that has suctioned the semiconductor chip 2.
And the thrust needle 13 is lowered (steps S19, S20). After that, the suction collet 12 is moved to convey the semiconductor chip 2 to a predetermined position (step S21). With the above, the pickup operation of one semiconductor chip 2 is completed, and in order to pick up the next semiconductor chip 2, the adhesive sheet 1 is moved by a predetermined distance (step S22).

[0039]

The chip pick-up method of the present invention is a laser datum attached to an adhesive sheet using a thrust needle.
The push-up from the side of the adhesive sheet diodes, the pushed up the laser diode switch to adsorb with the suction collet
In-up pick-up method, based on the current flowing between the push-up needle and the suction collet applying a voltage, a voltage is applied between the push-up needle and the suction collet, the push-up needle Stick the adhesive sheet
It is configured to determine whether or not it has been broken. Sanawa
Chi, whether or not the push-up needle has Tsu Tsukiyabu a pressure-sensitive adhesive sheet
By making the determination, the damaged laser diode can be accurately detected.

The chip pickup method of the present invention is
When the laser diode is sandwiched between the thrust needle and the suction collet, voltage is applied,
When the voltage is not applied, the thrust needle and the suction collet are set to the ground level , so it is possible to prevent the laser diode from being destroyed by an electrical shock when the strike is detected electrically. it can.

Further, the chip pickup method of the present invention is
Continuing that the thrust needle broke through the adhesive sheet
When detecting, counting the consecutive number of times of detection, when the count result exceeds a preset value, since the structure for stopping the pickup of the laser diode, it is possible to prevent a large amount of generation of bad chips .

[Brief description of drawings]

FIG. 1 shows a chip pickup method according to the present invention.
FIG. 3 is a block diagram showing the electrical configuration of an embodiment of a chip adsorption device for the purpose .

FIG. 2 is a flowchart showing the main operation of one embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a state of pickup of a laser diode .

FIG. 4 is an explanatory diagram showing a state of pickup of a laser diode .

[Explanation of Codes] 1 Adhesive sheet 2 Laser diode (semiconductor chip) 12 Adsorption collet 13 Push-up needle 14 Pass / fail judgment unit 15 Voltage application unit 16 Stop judgment unit

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-60-89938 (JP, A) JP-A-63-79077 (JP, A) JP-A-1-25839 (JP, A) JP-A-5- 121525 (JP, A) JP 5-180899 (JP, A) Actual development 5-81741 (JP, U) Actual development 3-76178 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21/68 H01L 21/52 H01L 21/301 H01L 21/66 G01R 31/26 G01R 1/06-1/073

Claims (3)

(57) [Claims] 1. A chip pick-up method in which a laser diode attached to an adhesive sheet is pushed up from the side of the adhesive sheet using a push-up needle and the pushed up laser diode is sucked using a suction collet. in, on the basis of the current flowing between the push-up needle and the suction collet voltage is applied, a voltage is applied between the push-up needle and the suction collet, the push-up needle
A method of picking up a chip, comprising determining whether or not the material has broke through the adhesive sheet . 2. A voltage is applied when the laser diode is sandwiched between the projecting needle and the suction collet, and when no voltage is applied, the projecting needle and the suction collet are removed. The chip according to claim 1, wherein the chip is a ground level.
Pickup method . 3. The protrusion needle protrudes the adhesive sheet.
Upon detecting successively that broke come, and counts the consecutive number of times of detection, when the count result exceeds a preset value, it stops the pickup of the laser diode
Ji of claim 1 or claim 2 wherein that
Pickup method .