KR100545195B1 - Standard mechanical interface system and control method of the same - Google Patents

Abstract

The present invention relates to a SMIF system and a control method thereof, which can prevent a drop phenomenon caused by the separation of the pod plate on which the wafer carrier is not separated from the housing, and the system of the present invention provides a pod plate on which the wafer carrier is seated. And a pad assembled with the pod plate and including a housing covering the wafer carrier and a sealing material sealing the pod plate and the housing; A port including a port plate on which the pod plate is seated, a sensing unit for detecting whether the pod plate is disposed at a proper position of the port plate, and a coupling unit for selectively coupling and separating the pod plate from the housing; A driving unit which enables wafer transfer by moving the housing or the pod plate after the pod plate and the housing are separated; And a control unit for selectively driving the driving unit in response to a detection signal from the sensing unit to return the housing or the pod plate to its original position when the housing or the pod plate is moved by the driving unit.

SMIF, POD, PORT, Pod Plate, Wafer, Cassette, Arm, Latch, Sticking

Description

SMIF system and its control method {STANDARD MECHANICAL INTERFACE SYSTEM AND CONTROL METHOD OF THE SAME}

1 is a perspective view showing a schematic configuration of a SMIF system according to an embodiment of the present invention,

2 is a cross-sectional view of FIG.

3 is a schematic block diagram illustrating a configuration of a sensing unit of FIG. 1.

The present invention relates to a SMIF system, and more particularly, to a SMIF system and a control method thereof, which can prevent a drop phenomenon caused by the pod plate on which the wafer carrier is not separated from the housing.

SMIF (Standard Mechanical Interface System) is a peripheral device of a semiconductor device that performs a semiconductor manufacturing process, and is used to load or unload a semiconductor wafer or a wafer carrier on which the wafer is stored into a semiconductor device for performing a unit process.

The SMIF system includes a pod (POD) for accommodating the wafer carrier, a port (PORT) for storing or withdrawing the pod, and a driving unit provided inside or outside the port.

The pod includes a pod plate on which a wafer carrier is seated, and a housing assembled with the pod plate and covering the wafer carrier, and the pod plate is provided with a sealing material to prevent injection of air or the like into the pod. At this time, the sealing material is disposed in a substantially rectangular shape along each side of the pod plate serves to seal the gap between the housing and the pod plate when the housing is selectively fastened to the pod plate.

The port for storing or withdrawing the pod includes a port plate on which the pod plate is seated, and the port plate includes a pod positioning pin, a pod sensor, and a latch pin.

The pod positioning pins are respectively inserted into insertion holes formed in the lower surface of the pod door to place the pod at a desired position, and the pod sensor serves to detect the presence or absence of the pod. In addition, the latch pin is selectively engaged with the engaging groove formed on the rotating plate provided on the lower surface of the pod plate, thereby allowing the hook provided on the pod plate to be selectively engaged with the hook groove of the housing, thereby engaging and separating the pod plate to the housing. .

On the other hand, after the pod plate and the housing are separated, the driving unit enables wafer transfer by the arm by moving the housing upward or by moving the pod plate downward. Of course, in the latter case of moving the pod plate to the lower side may be provided with a port door that the port plate of the port is lowered by the drive unit.

However, in the conventional SMIF system, when the housing or the pod plate is raised or lowered in the vertical direction by the driving unit after the pod containing the wafer carrier and the housing are separated, the pod plate is stuck due to the sticking phenomenon by the sealing material. They are raised together without being separated from the housing, or only the port door is lowered and the pod plate remains engaged with the housing.

In addition, when the pod plate is raised together with the housing or remains coupled to the housing as described above, the pod plate is separated from the housing by a small impact or gravity and falls, thereby falling together with the pod plate. Wafers are broken.

Accordingly, the present invention is to solve the above problems, the present invention, when the pod plate is not separated from the housing due to the sticking phenomenon by returning the pod plate to its original position and then attempting to remove the pod plate falling again An object of the present invention is to provide a SMIF system and a method of controlling the same, which can prevent wafer damage caused by the wafer.

The present invention to achieve the above object,

A pod including a pod plate for mounting a wafer carrier, a housing assembled with the pod plate and covering the wafer carrier, and a seal for sealing the pod plate and the housing;

A port including a port plate on which the pod plate is seated, a sensing unit for detecting whether the pod plate is disposed at a proper position of the port plate, and a coupling unit for selectively coupling and separating the pod plate from the housing;

A driving unit which enables wafer transfer by moving the housing or the pod plate after the pod plate and the housing are separated;

A control unit for selectively driving the driving unit to return the housing or the pod plate to its original position when the housing or the pod plate is moved by the driving unit;

It includes.

According to a preferred embodiment of the present invention, the sensing unit is protruding to the port plate and the sensing bar to move to the lower or upper side in accordance with the presence or absence of the pod plate, and generates an on / off signal according to the position of the sensing bar It includes a light emitting element and a light receiving element. Of course, the sensing unit may be configured as a magnetic sensor that outputs an on / off signal depending on the presence or absence of the pod plate, and may be configured as other sensors, for example, a tact switch. As such, the sensing unit is not limited to the type thereof as long as the sensing unit can output an on / off signal according to the presence or absence of the pod plate.

When the driving unit moves the pod plate, the port plate may further include a port door that is separated from the port plate and moves the wafer carrier downward to the wafer transfer position, in which case the port door is lowered. The moving unit may include a transfer member coupled to the lower side of the port door, a linear gear screwed to the transfer member to transfer the transfer member in a vertical direction, and a motor connected to the linear gear to rotate the linear gear. Can be.

In addition, the present invention is a control method for controlling the SMIF system of the above configuration,

(A) driving the drive unit to move the housing or the pod plate to enable wafer transfer;

(B) receiving a signal from the sensing unit and determining whether the pod plate is separated from the housing;

(C) if it is determined in step (B) that the pod plate and the housing are not separated, returning the housing or the pod plate to the original position by driving the driving unit back to the step (A);

It provides a control method of the SMIF system comprising a.

According to a preferred embodiment of the present invention, the number of steps is repeated from step (A) to step (C), preferably 3 to 4 times, and the pod plate is not separated from the housing due to sticking. If not, separate them manually.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 illustrates a perspective view of an SMIF system according to an embodiment of the present invention, and FIG. 2 illustrates a cross-sectional view of FIG. 1.

As shown, the SMIF system of the present embodiment includes a pod 20 for accommodating the wafer carrier 10 and a port door 32 for storing or withdrawing the wafer carrier 10 in the pod 20. Port 30, a drive unit 40 provided inside the port 30 and coupled to the port door 32 to move the wafer carrier 10 in the vertical direction, and a control unit for controlling the drive unit 40 And 50.

The pod 20 includes a pod plate 22 on which the wafer carrier 10 is seated, and a housing 24 covering the wafer carrier 10 seated on the pod plate 22. Since the inside of the pod 20 having such a configuration is preferably maintained in a vacuum state, the pod plate 22 is provided with a sealing material 26 for preventing injection of air or the like into the pod 20.

In addition, a plurality of hooks (not shown) are provided around the outer surface of the pod plate 22, and a plurality of hook grooves are provided on the inner surface of the housing 24 corresponding thereto, thereby providing the pod plate 22 and the housing 24. ) Can be combined or separated. In addition, although not shown, a lower plate of the pod plate 22 is provided with a rotating plate interlocking with the hook, and a pair of locking grooves are formed therein so that the locking grooves are engaged with the latch pins 32a of the port door 32. Can be configured to actuate the hook. Hereinafter, the latch pin 32a may be represented as a coupling part.

The port 30 includes a port door 32 and a port plate 34. The port plate 34 acts to keep the lower surface of the pod 20 horizontally when placing the pod 20 on the port 30. The port plate 34 has a desired positive position on the port 30. Guide rails 36 are provided to guide the pods 20 in position.

The port door 32 is moved by the drive unit 40 in the vertical direction indicated by the arrow, and serves to transport the wafer carrier 10 on the pod plate 22, and positioning pins installed in the port door 32. 36 'are respectively inserted into insertion holes (not shown) formed in the lower surface of the pod plate 22, and serve to arrange the pod 20 at a desired position.

In addition, the port door 32 is provided with a sensing unit 38 for sensing whether the pod plate 22 is disposed at a proper position. In this embodiment, as shown in FIG. The sensing bar 38a protruding from the port door 32 at a height h and moving downwardly or upwardly depending on the presence of the pod plate 22 and on / off depending on the position of the sensing bar 38a. The sensing unit 38 is configured by including a light emitting element 38b and a light receiving element 38c for generating a signal, and a spring 38d for supporting the sensing bar 38a upward.

Although not shown, the detection unit 38 may be configured as a magnetic sensor that outputs an on / off signal depending on the presence or absence of the pod plate 22, and may be configured as any other sensor such as a tact switch. have. As such, the sensing unit 38 is not limited to the type and configuration as long as the sensing unit 38 can output the on / off signal according to the presence or absence of the pod plate 22.

The drive unit 40 includes a conveying member 42, a linear gear 44, and a motor 46. The conveying member 42 is coupled to the lower side of the port door 32, and one end of the conveying member 42 is screwed with a linear gear 44 installed vertically on one inner side of the port 30, and the linear gear 44. ) Is connected to the motor 46 by a belt 48 'to a pulley 48 which is axially coupled at its end.

Therefore, when the linear gear 44 is rotated by the rotation of the motor 46, the transfer member 42 coupled with the port door 32 moves in the vertical direction.

In the SMIF system having such a configuration, when the sticking phenomenon occurs due to the sealing material 26, the pod 20 may fall and the wafer W may be damaged as described above.

In order to solve this problem, the present invention is provided with the above-described sensing unit 38, a method of controlling the system of the present embodiment using the sensing unit 38 as follows.

When the pod 20 containing the wafer carrier 10 is seated on the port plate 32, the fastening between the housing 24 and the pod plate 22 is released by the action of the latch pin 32a.

Thereafter, when the motor 46 of the driving unit 40 is driven by the controller 50 or the operator, the wafer W accommodated in the wafer carrier 10 is loaded / unloaded into the semiconductor manufacturing equipment for performing a unit process. In order to do so, the wafer carrier 10 is lowered vertically to the working position where the wafer transfer arm 60 is located.

At this time, the controller 50 receives the signal from the detector 38 to continue lowering the wafer carrier 10 or reversely drives the motor 46 of the driver 40 to drive the wafer carrier 10. Will be raised.

That is, if an on signal (or an off signal) from the sensing unit 38 is continuously applied while the wafer carrier 10 is lowered, the controller 50 determines that the pod plate 22 is normally separated from the housing 24. After that, the wafer carrier 10 is continuously lowered.

If an off signal (or an on signal) is applied from the sensing unit 38 while the wafer carrier 10 is lowered, the controller 50 may cause the pod plate 22 to be stuck due to a sticking phenomenon by the sealing material 26. It is determined that the housing 24 is not normally separated. That is, when sticking occurs, the pod plate 22 remains unseparated from the housing 24, so that the sensing bar 38a of the port door 32 pressed by the pod plate 22 is raised. As a result, an off signal (or an on signal) is output.

Therefore, when the off signal (or the on signal) is input from the sensing unit 38 as described above, the controller 50 reversely drives the motor 46 to raise the wafer carrier 10. Accordingly, since the port door 32 is raised immediately after descending the protruding height h of the sensing bar 38a, that is, about 3 to 4 mm, the port door 32 is subjected to external shock or self-weight during the lowering operation of the port door 32. As a result, even if the pod plate 22 is separated from the housing 24, the wafer W may be damaged due to the fall.

Thereafter, the control unit 50 repeats the above-described lowering and raising operations of the port door 32 until the pod plate 22 is normally separated from the housing 24, for example, 3 to 4 times. If it is determined that the pod plate 22 is not separated from the housing 24 even after such a repetitive operation, a warning sound or the like may be output to enable manual operation by the operator (referring to the operation of separating the pod plate from the housing).

In the above description, the driving unit lowers the pod plate, but it is described as an example. However, it is apparent to those skilled in the art that the present invention can be applied to an SMIF system configured to raise the housing instead of lowering the pod plate.

As described above, the present invention is not limited to the above-described embodiments, but can be modified and practiced in various ways within the scope of the claims, the detailed description of the invention, and the accompanying drawings. Do.

According to the present invention as described above, when the sticking phenomenon occurs, by lowering the wafer carrier to a minimum height and then rising again, there is an effect that can prevent the wafer breakage due to falling of the wafer carrier.

Since the pressure signal from the pressure gauge and the on (or off) signal from the relief means both satisfy the specified value, the door of the load lock chamber is not opened, so even if an error occurs in the pressure gauge, the internal pressure of the load lock chamber is returned to atmospheric pressure. The door can be prevented from opening before being formed.

Therefore, there is an effect that can reliably prevent problems such as wafer contamination and cracking due to the door opening.

Claims (7)

A pod including a pod plate for mounting a wafer carrier, a housing assembled with the pod plate and covering the wafer carrier, and a sealing material sealing the pod plate and the housing; A port including a port plate on which the pod plate is seated, a sensing unit for detecting whether the pod plate is disposed at a proper position of the port plate, and a coupling unit for selectively coupling and separating the pod plate from the housing; A driving unit which enables wafer transfer by moving the housing or the pod plate after the pod plate and the housing are separated; And a controller for selectively driving the driving unit to return the housing or the pod plate to its original position when the housing or the pod plate is moved by the driving unit, in response to a detection signal from the sensing unit. The sensing unit includes a sensing bar protruding from the port plate and moving downwardly or upwardly according to the presence of the pod plate, and a light emitting device and a light receiving device generating an on / off signal according to the position of the sensing bar. system. The SMIF system of claim 1, wherein the port plate further comprises a positioning pin for seating the pod plate in place. delete The SMIF system of claim 1, wherein the port plate further comprises a port door separate from the port plate to move a wafer carrier downward to a wafer transfer position. According to claim 4, The drive unit for moving the port door downwards, the transfer member coupled to the lower side of the port door, the linear gear for screwing the transfer member to transfer the transfer member in the vertical direction, and is connected to the linear gear SMIF system comprising a motor for rotating a linear gear. A control method for controlling the SMIF system according to any one of claims 1, 2, 3 and 5, (A) driving the drive unit to move the housing or the pod plate to enable wafer transfer; (B) receiving a signal from the sensing unit and determining whether the pod plate is separated from the housing; (C) if it is determined in step (B) that the pod plate and the housing are not separated, returning the housing or the pod plate to the original position by driving the driving unit back to the step (A); Control method of the SMIF system comprising a. The control method of an SMIF system according to claim 6, wherein the control step is repeated as many times as the set number from step (A) to step (C).

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