KR100867107B1 - Method of compensating package misplace of pick and place system for semiconductor production - Google Patents

Abstract

The present invention relates to a method for correcting package distortion in a pick and place device that picks up and flips a package on a wafer and then offloads it to a reel pocket.

The present invention implements a new correction system for moving the picker to a corrected position by receiving the image information while the picker captures the image through vision and moves to correct the distortion of the package generated during pickup. It provides a package correction method for pick and place devices for semiconductor manufacturing equipment that can greatly improve overall productivity, such as increasing unit per hour (UPH).

Wafer Level Package, Pickup and Placing, Dual Picker, Package Calibration

Description

Package correction method of pick and place device for semiconductor manufacturing equipment {Method of compensating package misplace of pick and place system for semiconductor production}

1 is a plan view showing a pick and place device of the semiconductor manufacturing equipment

Figure 2 is a schematic diagram showing the configuration of a motor control card related to the control of the flip-over picker in the package correction method according to an embodiment of the present invention

3 is a graph illustrating a relationship in which a flip-over picker moves to a corrected position in a package correction method according to an exemplary embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

10: on-loading unit 20: working table

30: Transfer Picker 40: Flip Over Picker

50: off-loading unit 60: first vision device

70: second vision device 80: third vision device

90a, 90b, 90c: Straight line transport mechanism

The present invention relates to a package correction method of a pick and place device for semiconductor manufacturing equipment, and more particularly, by applying a new method of receiving a correction value and moving to a corrected target point while the picker moves, thereby generating an image after image capture and The present invention relates to a package correction method of a pick and place device for semiconductor manufacturing equipment which can reduce picker waiting time during a calculation time.

In recent years, interest in wafer level package (Wafer Level Package) technology that meets the trend of miniaturization of semiconductor devices has increased.

Wafer-level packaging technology is a semiconductor packaging technology that completes assembly on a wafer where chips are not separated, unlike conventional methods of packaging each chip cut from a wafer.

The application of such semiconductor package technology shortens the process of assembling semiconductors such as wiring connection and plastic package, and also realizes significant cost savings by eliminating the need for plastic, circuit board, and wiring connection wires, which are conventionally used for semiconductor assembly.

In particular, it is possible to manufacture a package having the same size as a chip, thereby significantly reducing the size of a conventional chip scale package type package, which has been applied for miniaturization of a semiconductor. The chip can be mounted, making it easier to manufacture large memory modules.

In such a wafer-level package, after the packaging process on the wafer is finished, a sawing process of separating individual packages on the wafer is performed, and then pick-and-place (Pickup) which distinguishes between good and bad packages and flips them to place them. & Placing) process should be performed.

Conventionally, the sawing process is performed using a separate sawing equipment, while the pick and place process has been performed manually.

As a result, a chipping occurs and a problem arises in that sorting cannot be performed precisely according to an operator.

In order to solve the problem of the manual pick-and-place process, Japanese Unexamined Patent Application Publication No. 8-130230 discloses that a picker picks up a package on a wafer, flips it, and then seats it on a position correction table. A technique of picking up and placing a package on a substrate is proposed. In addition, Japanese Laid-Open Patent Publication No. Hei 2-56945 discloses a picker on a wafer and flippering it, and then a separate picker is transferred to the substrate. Recently, most of the automation concepts have been introduced into the pick-and-place process.

In the pick-and-place device for performing the pick-and-place process, the picker is responsible for transferring and placing the package between the processes. In this case, when the picker corrects the package to compensate for the distortion of the package generated at the time of pick-up, the vision is roughly imaged. It takes 1msec to capture the image, 19msec to generate the image, 20msec to calculate the target point, and delays the time because the picker is waiting at the top during the image generation and calculation after capturing the image. Will result.

Thus, there is a limit to increase the overall productivity, such as a decrease in the package processing speed (UPH) per unit time due to the disadvantages such as the efficiency associated with the picker's associated operation during package transfer.

Accordingly, the present invention has been made in view of the above, and the picker has a vision for correcting the distortion of a package generated during pick-up in a pick-and-place device that picks up and flips a package on a wafer and then offloads it to a reel pocket. By implementing a new calibration system that captures the image and then moves it to the corrected position while receiving the image, the overall productivity can be greatly improved by increasing the unit per hour (UPH). An object of the present invention is to provide a package correction method for a pick and place device for semiconductor manufacturing equipment.

The present invention for achieving the above object is a package according to the inspection result of the vision device during the process of transferring the package to the off-loading side by the flip-over picker in the process of transporting the package picked up by the flip-over picker to the off-loading portion to be seated in the reel pocket It characterized in that to perform the correction of.

Further, the correction of the package according to the inspection result of the vision device may be performed by calculating the operation value according to the photographing of the second vision device for the package on the flip-over picker and the operation value according to the photographing of the third vision device for the alignment state of the reel pocket. While receiving the input, after the image capture of the second vision device, the flip-over picker is performed by receiving the operation information during the process of moving immediately.

In addition, when the flip-over picker immediately moves after capturing the image of the second vision device, the flip-over picker is moved toward the absolute reference point by applying an absolute reference point, and receives a correction value from the absolute reference point during the movement. And over-picker moving to the corrected target point.

In addition, the corrected target point acquires the pocket position information and the state information on the reel to be offloaded through the third vision device, and the position information and the state information thus obtained and the position information of the package obtained through the second vision device. And determining by mutually calculating the state information.

Hereinafter, a package correction method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a plan view illustrating a pick and place device of semiconductor manufacturing equipment.

As shown in FIG. 1, the pick and place apparatus includes an onloading unit 10 for wafer supply, a working table 20 for wafer seating and package separation, a transfer picker 30 for package transport, and a package 180 °. A flip over picker 40 for inversion, an offloading unit 50 for package overloading, and the like.

First, the on-loading unit 10 is a means for supplying a wafer after the packaging process and sawing process on the wafer.

The on-loading unit includes a cassette magazine in which a plurality of wafers are mounted, a loading picker for picking up a wafer from the cassette magazine and supplying the wafer to the working table 20.

The loading picker is installed to be movable along the loading rail installed in the X-axis direction, and serves to pick up the wafers mounted in the cassette magazine one by one and load them on the working table 20.

In addition, the working table 20 is a means for receiving the wafer from the on-loading unit 10 and seating it, while separating the respective packages on the wafer from each other.

The working table 20 is composed of a table main body on which the wafer is seated, and an expanding unit for reducing the gap between packages on the wafer seated on the table main body.

The working table 20 is installed so as to be movable in the X-axis and Y-axis directions by known linear moving means, so that each time a package is picked up from the wafer one by one, the working table 20 can be moved to the pick-up position. 1, X and Y correction may be performed according to the inspection result of the vision device 60, and in some cases, θ correction may also be performed.

A first vision device 60 for photographing a package alignment state on the wafer seated on the table is provided at an upper side of the pick-up position of the working table 20.

At this time, the photographing value provided by the first vision device 60 is used to control the operation of the working table 20 and the transfer picker 30 to correct X, Y, and θ of each package on the wafer.

That is, the working table 20 may perform X and Y correction on the package on the table according to the result of the first vision device 60, and the transfer picker 30 may perform the θ correction on the picked-up package. Can be done.

In addition, the transfer picker 30 is a means for absorbing the package from the working table 20 and sending it to the flip over picker side.

To this end, the transfer picker 30 is provided to be movable in the X-axis (horizontal axis) direction, the Y-axis (vertical axis) direction and the Z-axis (vertical axis) direction by a known linear moving means.

The transfer picker 30 is provided with a picker head for directly adsorbing a package by a vacuum force provided from an external vacuum source (not shown), wherein the transfer picker 30 is inspected by the first vision device 60. According to the correction value, the package is properly rotated in the θ direction so that the package can be adsorbed after the θ correction of the package is performed.

The transfer picker 30 is composed of a dual type picker which operates independently of each other and alternately absorbs the packages on the wafer one by one to the flip-over picker side.

Accordingly, while one transfer picker 30 picks up the package on the wafer and then transfers the package to the flip-over picker side, the other transfer picker 30 transfers the package in the form of picking up the package on the wafer. In addition, the package processing speed per unit time can be greatly increased.

In addition, the flip-over picker 40 is a means for inverting by 180 ° by a rotation operation in the state of absorbing the package received from the transfer picker 30 and then sent to the off-loading side.

The flip-over picker 40 can operate in five directions of X, Y, Z, θ, and flippering, and inverts the package through the operation in each direction, or in the X-axis direction and Y-axis. While performing the correction of the direction, the feed to the offloading unit side, the θ correction or the like.

In the case of the flip-over picker 40 as described above, the dual type of the transfer picker 30 operates independently of each other, inverts the packages received from the respective transfer pickers 30, and alternately transfers them to the offloading side. It consists of pickers.

Accordingly, since the flip over picker 40 and the transfer picker 30 are formed in a pair, the package transfer, inversion, and offloading process can be performed in an integrated manner, thereby increasing efficiency related to the picker operation. .

One side of the flip over picker 40 is provided with a second vision device 70 for capturing the alignment state of the package is inverted by the picker.

At this time, the second vision device 70 is configured to photograph the package adsorbed on the picker by using a reflector installed in the trajectory of the flip-over picker 40.

According to the photographing result of the second vision device 70, the flip-over picker 40 may be properly operated (corrected) to accurately offload the package without errors.

In particular, the flip-over picker 40 is capable of performing the x, y, θ correction of the package in accordance with the inspection result of the vision device during the transfer of the adsorbed package to the offloading side.

Normally, when the flip-over picker corrects a package to correct a package distortion caused by passing a package from a transfer picker, it takes approximately 1 msec to capture an image, 19 msec to generate an image, and 20 msec to calculate. If the picker waits at the top for a time (39 msec) during image generation and calculation, the picker's UPH drops.

In order to compensate for this, the present invention can greatly improve the UPH by providing a method of correcting by receiving operation information while the picker moves immediately after capturing an image of the second vision device.

In addition, the offloading unit 50 is a means for offloading the package received from the flip over picker 40.

The off-loading unit 50 is a reel provided with a plurality of pockets on which the package conveyed by the flip-over picker 40 is seated, a driving unit and a rail for guiding the reel, and a pocket installed on an upper portion of the reel. And a third vision device 80 for photographing the aligned state of the camera.

The operation value according to the photographing of the third inspection vision 80 is provided to the flip-over picker 40, and the flip-over is performed in consideration of both the operation value provided at this time and the operation value provided by the second vision device 70. The picker 40 is able to perform x, y, θ correction on the package.

That is, the flip over picker 40 may perform the x, y, θ correction of the package in consideration of both the package state of the pickup and the pocket state in which the package is to be accommodated.

The third inspection vision 80 may once again photograph a package offloaded in the reel pocket by the flip-over picker 40.

Photographing at this time checks the marking status of the package, and if it is determined to be good, normal continuous work is performed. If it is determined to be defective, the package is picked up again by the flip-over picker and sent to one reject line for processing.

In the off-loading unit 50, the sealing operation by heating is performed after the package is received in the pocket of the reel, thereby completing a packing state to be sent to a subsequent process.

Meanwhile, a flip over picker for implementing a package correction method provided by the present invention will be described.

The flip-over picker 40 is a dual type picker, and is provided in each direction by known linear transfer mechanisms 90a, 90b, and 90c provided in the X-axis direction, the Y-axis direction, and the Z-axis direction. It serves to transfer the package adsorbed from the transfer picker 30 to the offloading unit 50 while moving, and includes means for flippering the package, that is, 180 ° inversion.

The flip-over picker 40 is a mechanical mechanism for performing the θ correction may apply a known means.

Figure 2 is a schematic diagram showing the configuration of a motor control card associated with the control of the flip-over picker in the package correction method according to an embodiment of the present invention, Figure 3 is a flip-over pick in the package correction method according to an embodiment of the present invention It is a graph showing the relationship in which the Kerr moves to the corrected position.

As shown in Figures 2 and 3, the flip-over picker shows how to move to the corrected position by receiving the operation information while moving the image capture after moving through the vision device, the associated motor control card It shows the hardware configuration and relative / absolute coordinates.

To this end, the motor control card includes a motor I / O interface block, a motor control chip, and a fish-bus interface in a form capable of communication with each other, and a motor I / O interface connector and a fish-bus for signal input and output from the outside. Interface connector is provided.

The motor control chip for controlling the operation of the flip over picker provided in the present invention is a motor control chip having an absolute reference point.

For example, the conventional motor control chip moves after the corrected target point is determined, but the motor control chip of the present invention applies an absolute reference point so that once the flip-over picker moves toward the absolute reference point and moves, The flip-over picker receives the correction value from the absolute reference point and moves to the corrected target point.

In this case, the absolute reference point may be set by a specification when designing a device, and a correction value (corrected target point) for the absolute reference point may be set by vision results of the second vision device and the third vision device. .

For example, the pocket position information and the state information on the reel to be offloaded are acquired through the inspection vision, and the optimal position and the offloading position are determined by mutually calculating the position information and the state information and the position information and the state information of the package. Can be.

Therefore, the overall operating state of the pick and place device including the step of performing the package correction as described above are as follows.

First, a loading picker picks up a wafer mounted in a cassette magazine on the onloading unit 10 and loads it on the working table 20.

In this state, a film of the wafer seated on the working table 20 is expanded through the operation of the expanding unit, thereby increasing the distance between the respective packages.

When the expansion is completed in this way, the whole working table 20 moves to the pick-up position of the picker and waits using the X, Y axis linear transfer mechanism.

At this time, the first vision device 60 photographs the package alignment state on the wafer and provides the result to the working table 20 or the transfer picker 30 to pick up the package without error.

That is, it is possible to accurately pick up the package through θ correction of the transfer picker 30 or the working table 20.

Pickup of the package on the wafer is performed by a dual type picker, ie two transfer pickers 30.

For example, if one transfer picker 30 picks up one package and transfers it to the flip over picker 40 side, the other transfer picker 30 moves to the pick-up position in the meantime to remove the package on the wafer. Pick up.

In other words, while two transfer pickers 30 are operated alternately, the package can be picked up and transferred without waiting time.

At this time, the working table 20 takes the action of moving the next package to the pick-up position each time the package is picked up one by one, and the two transfer pickers 30 are sequentially picked up at one pick-up position. The package can be picked up.

The flip over picker 40, which has been handed the package from the transfer picker 30, rotates 180 ° on the spot to reverse the package.

In this case, the inverted package is photographed by the second vision device 70.

On the other hand, in the third vision device 80 in the off-loading unit 50 is taken of the pocket alignment state of the reel, the shooting result of the third vision device 80 at this time and the second vision device 70 ) Can be used for the x, y, θ correction of the flip over picker 40, and finally x, in consideration of the state of the package adsorbed to the flip over picker 40 and the pocket state of the reel where the package will be placed. Since y and θ corrections are made, the package can be accurately seated in the reel pocket.

In addition, after performing a check operation such as a marking state of the offloaded package through the third vision device 80, reject processing may be performed on the defective package.

After flipping the package, the flip-over picker 40, which has been photographed, moves to an upper portion of the reel pocket of the offloading unit 50 to offload the package into the reel pocket.

The package that is offloaded in the reel pocket of the offloading unit 50 is packaged through a sealing process while being carried along the rail, and then transported for a subsequent process, so that the pick and place process may be completed.

Here, the flip-over picker obtains the pocket position information and the state information on the reel to offload the package through the inspection vision, and calculates the optimal position information and the state information and the position information and the state information of the package by mutually computing Since the offloading position is calculated, the package can be offloaded accurately, and the correction at this time is also performed by receiving information while the flip-over picker is moving without waiting time, and thus a time-saving effect can be expected.

As described above, the present invention implements a new pick and place system that picks up a package on a wafer through a dual picker type, flips and offloads it to a reel pocket, thereby increasing a package processing speed (UPH) per unit time. Therefore, there is an advantage that can greatly improve the overall productivity.

Claims (4)

delete delete In the package correction method of the pick and place device for semiconductor manufacturing equipment, In the process of transferring the package picked up by the flip over picker 40 to the offloading unit 50 and seating in the reel pocket, the flip over picker 40 transfers the package to the offloading unit 50 side. Compensation of the package is performed by receiving the calculation value according to the photographing of the second vision device 70 for the package on the package 40 and the calculation value according to the photographing of the third vision device 80 for the alignment state of the reel pocket. When the flip-over picker 40 immediately moves after capturing the image of the second vision device 70, the flip-over picker 40 moves toward the absolute reference point by applying an absolute reference point and the absolute while And receiving the correction value from the reference point and moving the flip-over picker 40 to the corrected target point. The method of claim 3, wherein the corrected target point is obtained through the third vision device 80, the pocket position information and state information on the reel to be offloaded, and thus obtained position information and state information and the second vision device 70 The package correction method of the pick and place device for semiconductor manufacturing equipment, characterized in that for determining by calculating the position information and the status information of the package obtained through).

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