JPH06283592A - Suction operation confirming equipment for semiconductor chip - Google Patents

Abstract

PURPOSE:To judge whether a semiconductor chip is normally sucked and retained by a suction collet, when the semiconductor chip is picked up by the suction collet and carried to a specified destination. CONSTITUTION:A photo detector 11 or a light emitting element 17 is arranged in the suction hole 10 of a suction collet 9. The light emitting element 17 or the photo detector 11 is arranged in the carriage route of the suction collet 9. On the basis of whether the photo detector 11 receives the light from the light emitting element 17, it is judged whether a semiconductor chip (d) is normally sucked and retained by the suction collet 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suction confirmation device for semiconductor chips, and more specifically, when a semiconductor chip is conveyed using a suction collet, it is checked whether the semiconductor chip is correctly held by the suction collet. Regarding what you have to confirm.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, a wafer on which a large number of elements have been formed at once is diced into individual semiconductor chips, which are then bonded one by one to predetermined positions on a lead frame. The chip bonding method is adopted. A large number of semiconductor chips individually separated from the wafer are held on an expanding tape, and the semiconductor chips are picked up from the expanding tape one by one and conveyed to a bonding position.

For the above pickup, a suction collet having a suction hole on the lower suction surface is used. The suction collet is reciprocally transported between the pickup position from the expand tape and the bonding position on the lead frame by an appropriate handling mechanism.

The semiconductor chip peeled from the expand tape by an appropriate method such as pushing up of the pickup needle is sucked and held by applying a negative pressure to the suction hole against the lower suction surface of the suction collet. The adsorption state is maintained by continuing to apply the negative pressure.

When the suction collet reaches a predetermined bonding position on the lead frame, the suction collet presses the semiconductor chip against the lead frame to which an adhesive such as a conductive paste is attached in advance and releases the suction negative pressure. By doing so, the bonding operation of the semiconductor chip to the lead frame is performed.

As described above, when the semiconductor chip picked up from the expand tape is directly bonded on the lead frame as well as when the accurate positioning of the semiconductor chip is required, the expand tape is once placed on the positioning table. In some cases, a semiconductor chip that has been transported and positioned is picked up again and transported onto a lead frame. Even in this case, when carrying the semiconductor chip,
An adsorption collet similar to the above is used.

By the way, the suction collet sucks a semiconductor chip by a suction force. However, the suction collet must properly suck and hold the semiconductor chip due to misalignment with respect to the semiconductor chip during pickup, vibration during transportation, and the like. There are cases where you cannot do it. Then, a portion where the chips are not bonded is generated on the lead frame to which the semiconductor chips are sequentially bonded, and various problems occur in the subsequent steps of manufacturing the semiconductor device. For example, since there is no semiconductor chip that should be present, not only wire bonding is not performed correctly, but also the wire bonding mechanism may be damaged. Also, there is no semiconductor chip,
In addition, a portion which is not wire-bonded is packaged in a resin mold, and this portion naturally becomes a defective product, and the material is wasted.

[0008] Conventionally, in order to avoid the inconvenience of the conveyance of the semiconductor chip by the suction collet, means for confirming whether or not the semiconductor chip is suction-held by the suction collet is provided.

The conventional suction confirmation means detects the static pressure in the suction hole b of the suction collet a. That is, a pressure sensor c is provided on the side of the suction collet a to detect whether air is flowing or not in the suction hole b.

For example, as shown in FIG. 7, when the semiconductor chip d is correctly adsorbed and held by the adsorbing collet a, the pressure in the adsorbing hole is reduced, but there is no air flow or a slight air flow. Is.

On the other hand, when the semiconductor chip d is not adsorbed and held by the adsorbing collet a, the adsorbing hole b is open, so that an air flow is generated in the adsorbing hole. Therefore, the pressure inside the suction collet differs depending on whether the suction collet a holds the semiconductor chip d by suction or not, and it is possible to determine whether or not the suction collet holds the semiconductor chip. .

[0012]

However, even if the semiconductor chip d is suction-held by the suction collet a,
As shown in FIG. 8, the semiconductor chip d may not be attracted and held in the correct posture. The state shown in FIG. 8 shows a state in which the upper surface of the light emitting diode chip d is not in contact with the suction surface of the collet, but the side surface thereof is suctioned. The conventional suction state confirmation means cannot detect the state shown in FIG.

Even if the semiconductor chip d having the posture shown in FIG. 8 is conveyed to the bonding position, it is obvious that the correct chip bonding cannot be performed. Not only that, but also in the wire bonding process following the chip bonding process, there is a possibility of causing a serious failure.

As for the light emitting diode chip, as shown in FIG. 6, the chip itself has a light-transmitting property, and a gold pattern for wire bonding is formed on the upper surface. In view of the above-described structure of the light emitting diode chip, the present invention has an object to surely confirm whether or not the light emitting diode chip is properly suction-held with respect to the suction collet.

[0015]

In order to solve the above problems, the present invention takes the following technical means.

That is, a device for confirming whether or not a semiconductor chip is correctly adsorbed and held by an adsorption collet that conveys a semiconductor chip picked up at a pickup position to a predetermined destination, and receives light in an adsorption hole of the adsorption collet. While the element or the light emitting element is provided, the light emitting element or the light receiving element is provided in the conveyance path of the suction collet, and the semiconductor chip is correctly sucked on the suction collet depending on whether or not the light receiving element receives the light from the light emitting element. The feature is that it is determined whether or not it is held.

[0017]

The function and effect of the present invention is, in short, to determine whether or not a semiconductor chip is properly suction-held on the suction surface of the suction collet depending on whether or not light is transmitted through the suction hole of the suction collet. Is.

As described above, in the light emitting diode chip, the chip body has a light-transmitting property, and a part of the upper surface thereof is covered with the non-light-transmitting gold pattern. Therefore,
As long as this light-emitting diode chip is properly suction-held with respect to the suction collet, the non-translucent gold pattern will block the suction hole, and the light-emitting element provided inside or outside the suction collet Light cannot pass through this adsorption hole.

Therefore, when the light receiving element does not receive the light from the light emitting body, it may be determined that the light emitting diode chip is correctly attracted and held by the attraction collet.

On the other hand, when the light-emitting diode chip is not adsorbed on the adsorption collet, the adsorption hole is open, so that the light from the light-emitting body can reach the light-receiving element through the adsorption hole. .

Further, even if the light-emitting diode chip is adsorbed to the adsorption collet, but is not adsorbed in the correct posture, that is, when the side surface of the light-emitting diode chip is adsorbed to the adsorption collet, the chip body. Has a light-transmitting property and the non-light-transmitting gold pattern does not cover the suction hole, so that the light from the light-emitting body passes through the suction hole through the inside of the light-emitting diode chip having a light-transmitting property. be able to.

Therefore, when the light receiving element receives the light from the light emitting body, the adsorption collet does not hold the light emitting diode chip or does not take the correct posture even if it is held. It will be. In this way, when the light receiving element receives light, it can be determined that the light emitting diode chip is not properly suction-held by the suction collet.

As described above, according to the present invention, it is possible to easily confirm whether or not the semiconductor chip is held by the suction collet in the correct posture, and it is possible to remarkably reduce the chip bonding failure with respect to the lead frame and to reduce the semiconductor device. The yield in manufacturing can be improved.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will be described below.
A specific description will be given with reference to the drawings.

FIG. 1 shows a pickup for a semiconductor chip d.
The whole structure of an example of the bonding apparatus 1 is shown. A large number of semiconductor chips d, which are individually separated from the semiconductor wafer by dicing, are carried on the expand tape 2, and the expand tape 2 is held on the XY actuator 4 while being stretched on the holding frame 3. It

Below the expanding tape 2, a tape guide 5 having a function of separating individual semiconductor chips d on the expanding tape 2 from the expanding tape 2 is fixedly arranged. An optical system recognition device 6 is arranged above the expandable tape 2 in correspondence with the planar position of the tape guide 5. The XY actuator 4 is stretched on the holding frame 3 so that the semiconductor chip d to be picked up is guided right above the tape guide 5 according to the recognition information from the optical system recognition device 6. 2 is moved in the XY directions.

As shown in FIG. 2, the tape guide 5 has a pick-up needle 8 which is retracted from a vacuum hole 7 formed in the top surface of the cylindrical member 5a, and is picked up as described above. When the position adjustment of the semiconductor chip to be performed is performed, the pickup needle 8 moves upward and the semiconductor chip d on the pickup needle 8 is peeled off from the expanding tape 2.

The adsorbing collet 9 is brought into contact with the upper surface of the semiconductor chip d so as to be in tandem with the peeling operation of the semiconductor chip d from the expanding tape 2, and a negative pressure is applied to the adsorbing hole 10 of the adsorbing collet 9. By acting, the semiconductor chip d is adsorbed and held by the adsorbing collet 9.

The suction collet 9 that picks up the semiconductor chip d from the expanding tape 2 and holds it by suction is moved to the lead frame F by a not-shown handling mechanism, and is attached to the lead frame F in advance by applying a conductive adhesive. The semiconductor chip d is bonded to the lead frame F by pressing the semiconductor chip d to a predetermined portion and releasing the suction force at the same time.

After the chip bonding, the suction collet 9 returns to the above-mentioned pickup position and repeats the same pickup operation or bonding operation as above.

As shown in detail in FIG. 3, the suction collet 9 is provided with a collet piece 9a having a suction surface having a suction hole 10 opened at the lower end. In the present embodiment, the collet piece 9a is connected to the lower end of a cylindrical hollow tube 9b having a bottom. The suction hole 10 formed in the collet piece 9a is formed so as to penetrate in the vertical direction, and a light receiving element 11 such as a photodiode is attached to the upper bottom portion of the hollow tube 9b. The photodiode is preferably arranged on the axis of the vertically extending suction hole 10.

A vacuum hose 13 is connected to the side port 12 of the hollow tube 9b, and the vacuum hose 13 is connected to a vacuum source 15 via a solenoid valve 14. A pressure sensor 16 for detecting static pressure in the hose is connected to an intermediate portion of the vacuum hose 13.

On the other hand, a light-emitting body 17 such as a lamp is arranged below the moving path of the suction collet 9 having the above structure.

The light receiving signal of the photodiode 11 and the detection signal of the pressure sensor 16 are input to the control device 18. The control output from the control device 18 is connected to a solenoid valve 14 for turning on / off the suction negative pressure to the collet 9. In the chip pickup / bonding apparatus 1 already described with reference to FIG. 1, the XY actuator 4 is driven based on the recognition information from the optical system recognition apparatus 6, and then the pickup needle 8 of the tape guide 5 is driven. The control of the above, or the control of the handling mechanism for moving the collet 9 is performed by an appropriate control device, but such a control device and the control device 18 in FIG. 3 can be shared.

Next, when the device is constructed so that the light emitting diode chip d as shown in FIG. 6 is picked up from the expanding tape 2 and bonded on the lead frame F, the semiconductor chip d is correctly adsorbed to the adsorption collet 9. A control method for determining whether the data is held will be described.

As shown in FIG. 6, a light emitting diode chip d is formed by providing a gold pattern dp for wire bonding on the upper surface of a dice-shaped gallium arsenide brown semitransparent chip body.

When the suction collet 9 is at the position where the chip d should be suction-held on the suction collet 9, for example, in the outward path from the pickup position to the bonding position, the pressure sensor 1
From the pressure signal from 6, it is possible to determine whether or not the tip d is adsorbed and held by the collet 9. When the chip d is adsorbed to the collet 9, since the adsorption hole 10 of the collet 9 is closed, there is no air flow inside the collet 9 or the vacuum hose 13.
Or it is extremely small. On the other hand, when the chip d is not adsorbed on the adsorption collet 9, the adsorption hole 10 is opened, so that external air is sucked and the air flows into the collet or the vacuum hose. Therefore, the magnitude of the pressure detected by the pressure sensor 16 is different depending on whether the chip d is adsorbed or not, and the value of the chip d depends on whether the value is larger or smaller than a certain threshold value. The presence or absence can be determined.

If it is determined that the suction collet 9 is not sucking the chip d, the control device 18 stops the movement of the suction collet 9 and controls each mechanism to perform the pickup operation again at the pickup position. .

When it is determined that the chip d is adsorbed by the adsorption collet 9, the light receiving signal from the light receiving element 11 when the adsorption collet 9 passes above the light emitting body 17 is analyzed. .

Even if the diode chip d is adsorbed to the adsorption collet 9, for example, as shown in FIG.
In some cases, the chip d is misaligned, or the side surface of the chip d is adsorbed as shown in FIG. 5, and in either case, proper bonding cannot be performed to the lead frame.

As described above, in the chip d to which the collet 9 is attracted in this embodiment, as shown in FIG. 6, the non-translucent gold pattern dp is formed on the upper surface of the semitransparent dice chip. It is a thing. Therefore, FIG.
If the side of the chip is adsorbed as shown in,
The gold pattern does not block the adsorption holes 10, and therefore
Light from the light emitting body 17 can reach the light receiving element 11 arranged in the collet through the chip d or the suction hole 10.

Further, as shown in FIG. 4, even when the chip d attracted to the collet 9 is misaligned, the gold pattern d
p partially blocks the adsorption hole 10, and the light emitting member 17
The light from can reach the light receiving element 11.

When the chip d is correctly attracted to the collet 9 as shown in FIG. 2, the gold pattern dp closes the attraction hole 10, so that the light from the light emitting body 17 is received by the light receiving element 11 in the collet. Never reach.

Therefore, when the collet 9 passes above the light emitting body 17 as described above, the light receiving element 1 in the collet 9
Depending on the amount of light that 1 receives, as shown in FIG. 4 or 5,
A state in which the tip d is not properly adsorbed and held by the collet 9 is detected.

As described above, when it is determined that the tip d is held in the collet 9 but is not held correctly, the controller 18 closes the solenoid valve 14 and the inside of the collet 9, for example. Release the negative pressure of. Then, the chip d that is not properly attracted and held as described above is dropped below without being bonded under the lead frame. Then, the collet 9 is returned to the pickup position again, and the pickup operation from the expanding tape 2 is performed again.

In the above, by detecting the pressure inside the collet, it is first judged whether or not the chip d is held in the collet 9, and if it is held, the light from the light-emitting body 17 is further emitted. Light receiving element 1 in collet
Although a two-step operation of determining whether or not the chip is correctly held depending on whether 1 is received, the determination by pressure detection is omitted, and the chip is set on the collet only by the signal from the light receiving element 11. It is also possible to judge whether or not it is properly held.

As described above, according to the present invention, when the light-emitting diode chip d is picked up from the expand tape 2 by the suction collet 9 and is bonded on the lead frame F, it is always properly sucked and held by the collet 9. Lead frame F
You will be able to bond to. As a result, chip bonding mistakes are drastically reduced and the product yield is significantly improved.

Of course, the scope of the present invention is not limited to the above embodiments. In the embodiment, the luminous body 17
Is provided outside the collet and the light receiving element 11 is provided inside the collet 9, but conversely, even if the light emitting element 17 is provided inside the collet and the light receiving element 11 is provided outside the collet, the same operational effect is obtained. Can be expected.

In the above embodiment, the semiconductor chip picked up from the expanded tape is conveyed to the lead frame, but it does not matter from which place the semiconductor chip is picked up and to which place the semiconductor chip is conveyed. . When picking up a semiconductor chip or bonding it to a lead frame, there is a case where the chip picked up from the expand tape is directly transferred onto the lead frame and bonded to the lead frame as described above. In some cases, the chips, which are transported to the positioning table and whose position or orientation is adjusted, may be transported onto the lead frame by another transport system. Also in this case, the suction collet is usually used, and the present invention can be applied without any problem.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an example of a semiconductor chip pickup / bonding device to which the device of the present invention is applied.

FIG. 2 is an enlarged vertical sectional view of a tape guide.

FIG. 3 is a schematic configuration diagram showing a main part of the device of the present invention.

FIG. 4 is a cross-sectional view showing an example in which a semiconductor chip is improperly adsorbed by an adsorption collet.

FIG. 5 is a cross-sectional view showing an example in which a semiconductor chip is improperly adsorbed to an adsorption collet.

FIG. 6 is an enlarged perspective view of a light emitting diode chip which is an example of a semiconductor chip used in the present invention.

FIG. 7 is a cross-sectional view of an example of a conventional suction collet.

FIG. 8 is a diagram showing a problem of a conventional example, showing a state in which a semiconductor chip is improperly adsorbed to an adsorption collet.

[Explanation of symbols]

 9 Adsorption collet 10 Adsorption hole (of adsorption collet) 11 Light receiving element 17 Light emitter

Claims (1)

[Claims] 1. A device for confirming whether or not a semiconductor chip is correctly adsorbed and held by an adsorption collet that conveys a semiconductor chip picked up at a pickup position to a predetermined destination, and light is received in an adsorption hole of the adsorption collet. While the element or the light emitting element is provided, the light emitting element or the light receiving element is provided in the conveyance path of the suction collet, and the semiconductor chip is correctly sucked on the suction collet depending on whether or not the light receiving element receives the light from the light emitting element. An adsorption confirmation device for a semiconductor chip, characterized in that it is determined whether or not it is held.