JP2006066636A - Conveying apparatus, its method, and exposing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conveying apparatus capable of conveying a wafer in a shorter time. <P>SOLUTION: In wafer exchange, a non-exposed wafer 510 is placed on a load arm 310 and is conveyed to the upper space of a wafer stage 210. An exposed wafer 520 on the wafer stage 210 is lifted by a vertical table 220, and is transferred to an unload arm 320 moving to the upper space of the wafer stage 210 (on the side of the wafer stage 210 of the load arm 310 and the non-exposed wafer 510 of the upper space). The unload arm 320 with the exposed wafer 520 placed thereon starts to shunt, and the vertical table 220 rises, just after the exposed wafer 520 reaches a location where it does not mechanically interfere with the vertical table 220, to receive the non-exposed wafer 510 from the load arm 310. Compared with a prior art case where it waits for the rise of the vertical table 220 until the exposed wafer 520 reaches a location where it does not mechanically interfere with the non-exposed wafer 510, the non-exposed wafer 510 can be placed more early on the wafer stage 210. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is suitable for application to an exposure apparatus used in a photolithography process when manufacturing an electronic device such as a semiconductor element, for example, and a transport apparatus and transport method for transporting an object such as a substrate, and the transport apparatus. The present invention relates to an exposure apparatus that transports a substrate using the same.

In the manufacture of electronic devices such as semiconductor devices, liquid crystal display devices, CCD imaging devices, plasma display devices, or thin film magnetic heads (hereinafter collectively referred to as electronic devices), an exposure apparatus is used to manufacture a photomask or reticle (hereinafter referred to as an electronic device). The image of the fine pattern formed on the reticle) is projected and exposed on a semiconductor wafer or a substrate such as a glass plate (hereinafter collectively referred to as a wafer) coated with a photosensitive agent such as a photoresist.
There are various types of exposure apparatuses, but step-and-repeat type projection exposure apparatuses (steppers) and step-and-scan type projection exposure apparatuses (scanning steppers) are widely used.

In this type of exposure apparatus, in order to sequentially expose the reticle pattern onto one lot of wafers, it is necessary to load the wafer to be exposed on the wafer stage and unload the exposed wafer from the wafer stage. For this purpose, the exposure apparatus is provided with a wafer loader system for exchanging the wafer on the wafer stage.
There are various configurations of the wafer loader system, but as one of the forms that have been widely used in the past, the unexposed wafer is moved along the linear guide and loaded into the upper space of the wafer stage moved to the loading position. And a load arm that moves along a linear guide, and an unload arm that unloads the exposed wafer from the upper space of the wafer stage moved to the wafer exchange position (loading position) is known. Yes. In this configuration in which the wafer is carried in and out of the wafer stage by the load arm and the unload arm, the wafer stage and the wafer stage are usually moved by the upper and lower tables that move in the vertical direction from the wafer placement surface of the wafer stage. The wafer is transferred to and from the load arm or unload arm in the upper space of the wafer stage.

The wafer exchanging operation by such a conventional wafer loader system will be specifically described with reference to FIGS.
Here, the operation of unloading the exposed wafer placed on the wafer stage from the wafer stage and loading a new unexposed wafer onto the wafer stage will be described.

FIGS. 8A to 8D and FIGS. 9A to 9D are diagrams for explaining the wafer exchange operation.
In this wafer loader system, first, as shown in FIG. 8A, an unexposed wafer 510 is placed on a load arm 310 and moved to a wafer delivery position P 1 in the upper space of the wafer stage 210.
Next, the upper and lower tables 220 are raised as shown by arrows in FIG. 8A, and the exposed wafer 520 is lifted from the wafer stage 210 as shown in FIG. 8B.

Next, the unload arm 320 is moved as indicated by an arrow in FIG. 8B, and this is the wafer transfer position P1 in the upper space of the wafer stage 210 and below the exposed wafer 520 (on the wafer stage 210 side). ) As shown in FIG.
In this state, the upper and lower tables 220 are lowered as indicated by arrows in FIG. 8C, and the exposed wafer 520 held on the upper and lower tables 220 is moved onto the unload arm 320 as shown in FIG. 8D. Placed on.

Next, as shown by an arrow in FIG. 8D, the unload arm 320 on which the exposed wafer 520 is placed is retracted from the wafer delivery position P1 in the upper space of the wafer stage 210, and then the load arm 310 is moved. As shown in FIG. 9A, the upper and lower tables 220 are raised so as to receive the unexposed wafer 510 placed on the substrate.
FIG. 10 shows the relative positional relationship of the load arm 310 and the unexposed wafer 510, the unload arm 320 and the exposed wafer 520, and the upper and lower tables 220 viewed from above in the plane.

9A and 10, the exposed wafer 520 placed on the unload arm 320 does not interfere with the unexposed wafer 510 placed on the load arm 310, that is, in the horizontal direction. When the position reaches a position (unloading completion position) P4 that does not overlap, the movement of the unload arm 320 is once stopped, and the unload arm 320 is accurately positioned at the position P4. When positioning of the unload arm 320 (exposed wafer 520) is completed, it is assumed that the exposure of the exposed wafer 520 from the above-described upper space (completion of unloading) is confirmed, as shown by an arrow in FIG. The upper and lower tables 220 are raised, and the unexposed wafer 510 placed on the load arm 310 is lifted as shown in FIG. 9B.
Further, the unload arm 320 starts to move again when the positioning is confirmed, and delivers the exposed wafer 520 to another transfer means (for example, another transfer robot) as shown in FIG. 9B. Move to a position P5 (wafer delivery position P5).

Regarding the movement of the unload arm 320 at this time, the relationship between time and speed is shown in FIG.
As shown in FIG. 11, the unload arm 320 accelerates from the wafer delivery position P1 in the upper space of the wafer stage 210 to a constant speed, then moves toward the position P4, decelerates immediately before the position P4, and temporarily stops at the position P4. The operation is stopped, and it is confirmed that the unload arm 320 and the exposed wafer 520 placed thereon have reached the unloading completion position. Thereafter, it is accelerated again to a constant speed and moved to the wafer delivery position P5.

Next, as shown by an arrow in FIG. 9B, the load arm 310 is retracted from the upper space of the wafer stage 210, and then the unexposed wafer 510 placed on the upper and lower tables 220 is placed on the wafer stage 210. 9C, the upper and lower tables 220 are lowered as indicated by arrows in FIG.
FIG. 12 shows the relative positional relationship of the load arm 310, the unexposed wafer 510, and the upper and lower tables 220 at this time as viewed from above the plane.
As shown in FIGS. 9C and 12, the load arm 310 does not interfere with the unexposed wafer 510 placed on the upper and lower tables 220, that is, a position where the position does not overlap in the horizontal direction (retraction complete). Once the position is retracted to P2, the load arm 310 once stops moving. Then, the upper and lower tables 220 are lowered as indicated by arrows in FIG. 9C, and the unexposed wafer 510 is placed on the wafer stage 210 as shown in FIG. 9D.
The load arm 310 starts to move again when the positioning is confirmed, and the next unexposed wafer 510 is transferred to another transfer system (for example, another transfer robot, a delivery table, etc.) as shown in FIG. 9D. ) To a position (wafer receiving position) P6 for receiving.

Regarding the movement of the load arm 310 at this time, the relationship between time and speed is shown in FIG.
As shown in FIG. 13, the load arm 310 accelerates from the wafer transfer position P1 in the upper space of the wafer stage 210 to a constant speed, moves to the position P2, stops temporarily at the position P2, and the load arm 310 moves to the position P2. Confirm that it has been reached. Then, it accelerates to a constant speed again and moves to position P6.

By the way, conventionally, in an exposure apparatus, it has been demanded to perform an exposure process at a high throughput and efficiently manufacture an electronic device or the like. However, in recent years, the demand has been further increased. For this purpose, even in the above-described wafer loader system in which the wafers to be exposed are sequentially placed on the exposure stage (wafer stage) in the exposure apparatus, the exposed wafers can be unloaded safely and at high speed, and the unexposed wafers 510 can be safely and securely loaded. It is desired to carry in at high speed, that is, to perform wafer exchange efficiently at high speed.
Therefore, in a wafer loader system having a similar configuration, for example, by detecting a substrate misalignment during substrate transport, the substrate misalignment detection time is completely overlapped with the substrate transport time, thereby improving throughput. A method and the like have also been proposed (see, for example, Patent Document 1).
Re-publication 00/02239

In the wafer loader system configured as described above, the upper and lower tables, the load arm and the unload arm operate in sequence to transport the wafer. However, since it is necessary to transport the wafer safely, these parts and these The next transfer operation is performed after the wafers held by the respective parts are in a positional relationship that does not sufficiently interfere with each other.
In that case, once the movement of the movable part such as the load arm or the unload arm is temporarily stopped and the position thereof is accurately positioned, the respective parts are in a positional relationship that does not interfere with each other. Confirmation has been made.

Specifically, for example, as shown in FIG. 9A, the ascending operation of the upper and lower tables 220 for receiving the unexposed wafer 510 transferred by the load arm 310 is performed by the exposed wafer placed on the unload arm. The process is started after it is confirmed that the position P4 does not sufficiently interfere with the unexposed wafer in the planar direction (Y direction). For this purpose, as shown in FIG. 11, when the unload arm 320 reaches the unloading completion position P4, the unload arm 320 is temporarily stopped and positioned, and then the position is confirmed.
Further, as shown in FIG. 9C, when the upper and lower tables 220 on which the unexposed wafer 510 is placed are lowered (moved in the −Z direction), the load arm 310 that has transferred the upper and lower tables 220 and the unexposed wafer 510 are moved. It is started after it has been confirmed that the position has not interfered. For this purpose, as shown in FIG. 13, when the load arm 310 reaches the exit completion position P2, the load arm 310 is temporarily stopped and positioned, and then the position is confirmed.

  However, it is difficult to say that the timing of movement of each part in the past is optimally scheduled and controlled with respect to high-speed wafer exchange, and ensures an interval more than necessary with respect to not interfering with each other. For example, the waiting time until moving is long, and it may take time to replace the wafer. In addition, in order to confirm whether each movable part has reached a predetermined position that does not interfere with other movable parts or wafers, the movable part is stopped to perform positioning or position confirmation with high accuracy. This also increases the waiting time until the wafer moves, which is a factor that takes time to replace the wafer.

The present invention has been made in view of such problems, and an object of the present invention is to provide a transfer apparatus and a transfer method that can transfer an object such as a wafer in a shorter time.
Another object of the present invention is to provide an exposure apparatus capable of performing exposure processing efficiently by exchanging wafers at high speed by using such a transfer apparatus.

  In order to solve the above-described problems, a transport apparatus according to the present invention carries a stage (210) having a placement surface on which an object (500) is placed, and unloads from the placement surface on the stage (210). The object to be moved (520) can be moved in a direction perpendicular to the loading surface and the unloading arm (320) for unloading from the space above the stage to the unloading completion position (P4) outside the space above the stage. A movable table (220) that lifts the object to be carried out (520) placed on the placement surface into the space from the placement surface and delivers it to the carry-out arm (320), The object (520) by the unloading arm (320) before the unloading arm (320) completes the unloading operation of the object (520) to the unloading completion position (P4). Unloading Based on the information indicating the status (information indicating that reaches the position P3), having a control means for starting the movement to the vertical direction of the movable table (220) (see FIG. 1) (claim 1).

  In the transfer apparatus having such a configuration, for example, before the unloading operation in which the object (520) such as the exposed wafer is moved to the unloading completion position (P4) by the unloading arm (320) is completed (at the position P3). The movable table (220) starts to move in the vertical direction. Therefore, the next process using the movable table (220) can be started early for the time when the movable table (220) started to move quickly before the carry-out operation is completed.

  Another transport device according to the present invention includes a stage (210) having a placement surface on which the object (500) is placed, and an object to be placed on the placement surface on the stage (210). A carry-in arm (310) for carrying (510) into the space above the stage, and a table movable in a direction perpendicular to the mounting surface, and carried into the space by the carry-in arm. And a movable table (220) that receives the object (510) and places the object (510) on the placement surface, wherein the carry-in after the object (510) is delivered to the movable table (220) Based on the information indicating the state in which the arm (310) is retracted from the space to the retract completion position (P2), the movable table (220) is moved in the vertical direction without stopping the driving of the loading arm. Start Having a control unit that (see FIG. 1) (claim 2).

  In the transfer device having such a configuration, for example, after the transfer arm (310) after transferring the object (510) such as an unexposed wafer to the movable table (220) is moved to the retreat completion position (P2). The movable table (220) starts to move in the vertical direction without stopping the subsequent operation of the carry-in arm. Accordingly, the object (510) received by the movable table (220) is quickly placed on the placement surface of the stage (210) for a time that does not involve the operation of stopping the arm when the retracting operation is completed as in the prior art. be able to.

  In addition, another transfer apparatus according to the present invention includes a stage (210) on which an object is placed, and an object to be placed on a placement surface provided on the stage in a first space above the stage. A carry-in arm (310) to be carried in and an object to be carried out from the stage are located in the space above the stage, and from outside the second space from the second space closer to the stage than the first space. An unloading arm (320) for unloading to the unloading completion position and a table movable in a direction perpendicular to the mounting surface, the first object to be unloaded placed on the mounting surface described above A movable table (220) that lifts from the placement surface into the second space and delivers it to the carry-out arm, and receives the second object conveyed into the first space by the carry-in arm and places it on the placement surface. ) , Based on the information indicating the unloading state of the first object by the unloading arm before the unloading arm completes the unloading operation of the first object to the unloading completion position, or the object is placed on the movable table. The carry-out arm or the drive-in arm is driven based on information indicating the retraction state of the carry-in arm before the carry-in arm after delivery has completed the retreat operation from the first space to the retreat completion position. Control means for starting movement of the movable table in the vertical direction without stopping (see FIG. 1) (Claim 3).

  Preferably, the control means is arranged on the carry-in arm based on information indicating that the first object placed on the carry-out arm has moved to a position where it does not mechanically interfere with the movable table. In order to receive the second object placed on the movable table, the movable table is moved up along the vertical direction (Claim 4).

  Preferably, the control means moves the second object forward based on information indicating that the carry-in arm has moved to a position where it does not mechanically interfere with the second object placed on the movable table. In order to place the movable table on the placement surface, the movable table is lowered along the vertical direction (Claim 5).

  Preferably, the apparatus further includes a sensor that detects that the object placed on the carry-out arm has passed a position that does not interfere with the vertical movement of the movable table, and the control means includes the sensor The movement of the movable table is controlled on the basis of the output (Claim 6).

  Preferably, when the unloading arm moves to the unloading completion position, the unloading arm moves continuously without stopping until at least the passage of the position by the sensor is detected. ).

  Preferably, the loading arm further includes a sensor that detects that the movable table has passed through a position that does not interfere with an object placed on the movable table when the movable table moves in the vertical direction. The means controls the movement of the movable table based on the output of the sensor.

  Preferably, when the carry-in arm moves to the retreat completion position, the carry-in arm continuously moves without stopping until at least the passage of the position by the sensor is detected. ).

  Further, the transport method according to the present invention transports the first object placed on the placement surface on the stage from the placement surface, and carries the second object onto the placement surface. The first object is transported into the first space above the stage by a carry-in arm, and the table is movable in the direction perpendicular to the placement surface. A second step of moving an object in a second space on the stage side of the stage above the first space, and the first object existing in the second space, A third step of starting to move the movable table toward the first space while being carried out toward a predetermined unloading position outside the second space by the unloading arm; and in the first space The second object is moved from the transfer arm to the A fourth step of transferring to the moving table; and after the fourth step, the carry-in arm is moved while moving the move-in arm from the first space toward a predetermined position outside the first space. And a fifth step in which the movable table starts moving toward the placement surface without stopping the movement (claim 10).

  Preferably, in the third step, when it is detected that the first object received by the carry-out arm has passed a position that does not interfere with the movement of the movable table in the vertical direction, The movement is started (claim 11).

  Preferably, in the fifth step, when it is detected that the carry-in arm has passed a position that does not interfere with the movement of the second object placed on the movable table in the vertical direction, The movement of the movable table is started (claim 12).

  An exposure apparatus according to the present invention is an exposure apparatus that transfers an image of a pattern formed on a mask to a substrate via a projection optical system, and transports at least one of the mask and the substrate to a stage. As a device, any one of the above-described transfer devices is provided (claim 13).

  In this column, the reference numerals of the corresponding components shown in the attached drawings are shown for each component, but this is only for easy understanding and does not relate to the present invention. It is not intended that the means be limited to the aspects of the embodiments described below with reference to the accompanying drawings.

According to the present invention, it is possible to provide a transfer apparatus and a transfer method capable of transferring an object such as a wafer in a shorter time.
Further, by using such a transfer apparatus, it is possible to provide an exposure apparatus capable of performing exposure processing efficiently by performing wafer exchange at high speed.

An exposure apparatus according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a diagram showing a configuration of an exposure apparatus 10 according to the present embodiment, and particularly a diagram mainly showing a configuration of a wafer loader system 300 according to the present invention.
First, the overall configuration and overall operation of the exposure apparatus 10 will be described with reference to FIG.
In the following description, the left-right direction in the plane of FIG. 1 is the X-axis direction, the direction (vertical direction) perpendicular to the X-axis direction in the plane of FIG. 1 is the Y-axis direction, and these X-axis, Y-axis In the description, the direction perpendicular to the paper surface perpendicular to the axis is defined as the Z-axis direction. In an actual space, the XY plane is a horizontal plane, and the Y-axis direction is the vertical direction (vertical direction).

First, the overall configuration of the exposure apparatus 10 will be described focusing on the configuration of the wafer loader system 300 according to the present invention.
As shown in FIG. 1, the exposure apparatus 10 includes a chamber 100, an exposure apparatus main body 200, and a wafer loader system 300.
The interior of the chamber 100 is divided into an exposure chamber 101 and a loader chamber 102 by a partition wall 103. The exposure chamber 101 accommodates the exposure apparatus main body 200, and the loader chamber 102 accommodates most of the wafer loader system 300.

The exposure apparatus main body 200 transfers the reticle pattern onto a wafer 500 (hereinafter sometimes referred to as an unexposed wafer 510 or an exposed wafer 520 in correspondence with before and after exposure).
In FIG. 1, only the wafer stage 210 and the upper / lower table 220 on which the wafer 500 is placed are shown as the exposure apparatus main body 200, and the other components are not shown.

  The wafer stage 210 is configured to be movable in an XY two-dimensional direction on a surface plate (not shown) held by a vibration isolation pad (not shown). The wafer stage 210 transfers the reticle pattern on the surface plate via a wafer loading position for transferring the wafer to and from the wafer loader system 300 or a projection optical system (not shown) of the exposure apparatus main body 200. Move to the exposure position.

  An upper and lower table (movable table) 220 that protrudes upward (Z direction) from the stage surface of the wafer stage 210 and moves up and down in a direction perpendicular to the stage surface is provided at the center of the wafer stage 210. The upper and lower tables 220 move up and down when the wafer stage 210 is located at the wafer loading position, and transfer the wafer 500 between a load arm 310 and an unload arm 320 described later.

  Specifically, when the exposed wafer 520 is placed on the wafer stage 210, the upper and lower tables 220 are lifted to lift the exposed wafer 520 from the stage surface of the wafer stage 210. The lifted exposed wafer 520 is transferred from the upper and lower tables 220 to the unload arm 320 in the upper space of the wafer stage 210 and is carried out of the exposure apparatus main body 200.

  When the unexposed wafer 510 is loaded into the exposure apparatus main body 200, the unexposed wafer 510 is transferred to the upper space of the wafer stage 210 by the load arm 310. In this state, the upper and lower tables 220 are raised, so that the upper and lower tables 220 receive the unexposed wafer 510 from the load arm 310. Then, after the load arm 310 is retracted, the upper and lower tables 220 are lowered to place the unexposed wafer 510 on the wafer stage 210.

  There are various forms of the upper and lower tables 220. In this embodiment, the upper and lower tables 220 are moved in the Z direction at the same height (the same position in the Z direction at the tip) at three points not on a straight line in the stage surface. It is composed of three pins. However, in the drawing, the upper and lower tables 220 are simply shown in a circular shape.

The wafer loader system 300 is a substrate transfer system used for loading a wafer into the exposure apparatus main body 200.
Wafer loader system 300 conveys X guide 301 extending in the X-axis direction, and Y guide 302 extending in the Y-axis direction intersecting with X guide 301 above X guide 301 (the front side in FIG. 1, + Z side). Prepare as a guide. The Y guide 302 is provided in a state of penetrating the partition wall 103.

  Carrier tables 304 and 305 are arranged on the wall side (−Y side) of the chamber 100 of the X guide 301 in the loader chamber 102 at a predetermined interval in the X-axis direction. The carrier tables 304 and 305 are tables on which the open cassette OC is placed in the case of an operation mode in which a wafer is directly put into the exposure apparatus 10 using an open cassette (OC: Open Cassette) capable of storing a plurality of wafers. is there. Instead of the open cassette, a structure in which a FOUP (Front Opening Unified Pod) is placed may be used.

The open cassette OC or the hoop is connected between the outside of the exposure apparatus 10 and the loader chamber 102 via a not-shown opening / closing port that can be opened and closed by a door (not shown) provided on the side wall on the −Y side of the chamber 100 (loader chamber 102). It is put in and out between.
The open cassette OC or hoop may be transported by a manual guided vehicle (PGV) and manually inserted or removed by an operator, or after being transported by an automated guided vehicle (AGV). You may make it carry out automatically. Moreover, you may install on the carrier stands 304 and 305 from upper direction using OHT (Overhead Hoist Transfer).

On the X guide 301, a horizontal articulated robot (scalar robot) 303 that is driven by a driving device (not shown) and moves along the X guide 301 is provided.
The Y guide 302 includes a wafer load arm (loading arm) 310 (hereinafter simply referred to as a load arm 310) and a wafer unload arm (hereinafter simply referred to as a load arm 310) that are driven by a driving device (not shown) and move along the Y guide 302. A carry-out arm) 320 (hereinafter simply referred to as an unload arm 320) is provided.
A sensor (not shown) that detects that the load arm 310 and the unload arm 320 have reached predetermined positions is provided along the movement range of the load arm 310 and the unload arm 320 of the Y guide 302. In the present embodiment, this sensor includes a light shielding plate that moves together with the load arm 310 and the unload arm 320, and a photoelectric sensor that detects that light is blocked by the light shielding plate, and the load arm 310 or the unload arm 320. When each of the sensors reaches a predetermined position (when it passes), the photoelectric sensor is appropriately placed in the middle of the movement of the light shielding plate so that the light shielding plate blocks the light of the photoelectric sensor, thereby instantaneously passing the desired position. Can be detected. In the wafer transfer operation according to the present invention, it is detected by this sensor that the load arm 310 or the unload arm 320 has been retracted after passing through a predetermined retracted position, and the moving operation of the movable part in the next process is started.
A method of transporting the wafer 500 between the wafer loader system 300 and the wafer stage 210 by the load arm 310 and the unload arm 320 according to the present invention will be described in detail later.

  Further, at a position on the −X side of the −Y direction end portion of the Y guide 302, a turntable (not shown) between the carrier tables 304 and 305 for pre-alignment of the unexposed wafer 510 put into the exposure apparatus main body 200 (see FIG. A rotary table) 306 is disposed, and a wafer edge sensor (not shown) is disposed at a position spaced apart from the turntable 306 in the Y direction by a predetermined distance.

Further, when the exposure apparatus 10 is connected in-line with a coater / developer (not shown) that performs a pre-process and a post-process of the exposure process, it is near the side wall of the loader chamber 102 connected to the coater / developer, and X At the end portion of the guide 301 (in FIG. 1, the end portion on the −X side of the X guide 301), a wafer transfer table 307 for temporarily placing the wafer when the wafer is transferred between the apparatuses is provided.
The wafer delivery table 307 may have a configuration in which a dedicated delivery device is provided between the exposure apparatus 10 and the coater / developer and installed therein.
The wafer delivery table 307 may also serve as a temperature adjustment plate that adjusts the temperature of the wafer 500 put into the exposure apparatus 10 to be equal to the temperature of the exposure environment in the exposure apparatus main body 200.
The wafer loader system 300 is composed of these parts.

  The exposure apparatus 10 also has a control unit that controls each part of the exposure apparatus 10 so that the exposure apparatus 10 performs a desired operation as a whole. The control unit includes, for example, an exposure apparatus control unit that controls each unit of the exposure apparatus 10, a wafer loader control unit that controls each unit of the wafer loader system 300, and an overall control unit as a higher-level control unit of these control units.

  In the wafer loader system 300 according to the present invention, the wafer loader control unit controls each part of the wafer loader system 300 so that the wafer 500 is transported safely and efficiently. In particular, the wafer loader control unit loads the wafer 500 (the unexposed wafer 510 and the exposed wafer 520) on the wafer stage 210 at high speed and efficiently through the load arm 310 and the unload arm 320 by the method according to the present invention described later. Each part in the wafer loader system 300 is controlled so as to be exchanged.

Further, the exposure apparatus control unit and the wafer loader system control unit, or each control unit including the overall control unit added thereto, each wafer state of the lot put in the exposure apparatus 10, specifically, the exposure apparatus main body 200. And a function of sequentially storing the transfer state and processing state of each wafer loaded in the wafer loader system 300. More specifically, for example, information for specifying a wafer (for example, wafer ID information or information on which wafer in the lot is being processed), information on the position of each wafer, information on processing status, etc. Is stored in a non-volatile memory (for example, a flash memory or an EEPROM) in each control unit. Correspondingly, the wafer holding state in each wafer holding means, that is, in the wafer loader system 300, for example, the robot 303, the turntable 306, the wafer transfer table 307, the load arm 310, the unload arm 320, etc. Are also stored in the non-volatile memory in each control unit.
If this information is stored, for example, when an error occurs and the power is turned off or the device is reset, and the device is subsequently restored, by referring to these information, The state (the state of the apparatus immediately after the restoration) or the processing state of each wafer can be easily grasped, and the recovery can be efficiently performed in the best state.

Next, the overall operation of the exposure apparatus 10 having such a configuration will be described focusing on the wafer transfer operation in the wafer loader system 300 according to the present invention.
Here, the transfer of the wafer 500 will be described on the assumption that the exposure apparatus 10 is connected inline with the coater / developer.

The unexposed wafer 510 put into the exposure apparatus 10 is transferred to the wafer transfer table 307 of the wafer loader system 300 by a coater / developer (not shown) or a wafer transfer apparatus arranged between the coater / developer and the exposure apparatus 10. Placed.
The unexposed wafer 510 placed on the wafer transfer table 307 is received by the robot 303 of the wafer loader system 300. The robot 303 that has received the unexposed wafer 510 moves along the X guide 301 to the vicinity of the turntable 306 and places the unexposed wafer 510 on the turntable 306.

  When the unexposed wafer 510 is placed on the turntable 306, the turntable 306 is rotated by a drive system (not shown), whereby the wafer 510 held on the turntable 306 is rotated. While the wafer 510 is rotating, the edge of the wafer 510 is detected by the wafer edge sensor, and the direction of the notch of the wafer 510 and the amount of eccentricity between the center of the wafer 510 and the center of the turntable 306 (based on the detection signal) Direction and size). Then, the wafer loader control unit rotates the turntable 306 based on the result, and aligns the direction of the notch portion of the wafer W with a predetermined direction (pre-alignment operation).

The unexposed wafer 510 on the turntable 306 is received by the load arm 310 moved to a predetermined wafer receiving position. At this time, the load arm 310 determines the center of the wafer obtained in advance and the center of the turntable 306. Is moved to a position where the Y-direction component of the eccentric amount can be corrected, and then the unexposed wafer 510 is received.
The load arm 310 that has received the unexposed wafer 510 moves along the Y guide 302 toward the upper side of the wafer stage 210 waiting at a predetermined loading position.

When the load arm 310 transports the unexposed wafer 510 to above the wafer stage 210, the upper and lower tables 220 move upward (+ Z direction) and receive the unexposed wafer 510. At this time, the wafer stage 210 is slightly driven in the X-axis direction immediately before the unexposed wafer 510 is transferred from the load arm 310 to the upper and lower tables 220 so that the X component of the eccentric amount obtained previously is corrected.
When the upper and lower tables 220 receive the unexposed wafer 510, the upper and lower tables 220 descend in the direction of the wafer stage 210 (−Z direction) and place the unexposed wafer 510 on the wafer stage 210.

Then, the exposure apparatus main body 200 performs an exposure process on the unexposed wafer 510 (wafer 500) transferred onto the wafer stage 210.
In the exposure process, for example, each shot area on the wafer 500 on the wafer stage 210 is positioned at a projection position of a reticle pattern held by a reticle stage (not shown) by a projection optical system, and the reticle is illuminated with exposure light. And the operation of transferring the pattern of the reticle to each shot area via the projection optical system is repeated.
When exposure apparatus main body 200 is an apparatus that performs exposure using a scanning exposure method, the exposure process is performed by scanning a reticle (reticle stage) and wafer 500 (wafer stage 210) at a scan start position for exposing each shot area. And illuminating a slit-like illumination area on the reticle with exposure illumination light while synchronously moving the reticle and the wafer 500, and each shot on the wafer 500 via the projection optical system. This is performed by repeating the scanning exposure operation of sequentially transferring the region.

When the exposure process is completed, the wafer stage 210 moves to the unloading position, that is, the aforementioned loading position, and the upper and lower tables 220 move upward (+ Z direction) to lift the exposed wafer 520. The exposed wafer 520 is received by the unload arm 320, transferred to above the X guide 301, and transferred to the robot 303 waiting there.
The robot 303 conveys the exposed wafer 520 along the X guide 301 in the direction of the coater / developer and places it on the wafer transfer table 307. The wafer placed on the wafer delivery table 307 is received by a coater / developer (not shown) and subjected to processing such as baking and development.

Such operations of the exposure apparatus 10, in particular, the transfer operation of the wafer 500 in the wafer loader system 300 are sequentially and concurrently performed. That is, the wafer transfer table 307 receives the next unexposed wafer 510 or the exposed wafer 520 unloaded from the exposure apparatus 10 at the time when the next exposure target wafer 500 (unexposed wafer 510) or The next wafer 500 (exposed wafer 520) to be unloaded is placed.
The unexposed wafer 510 placed on the wafer transfer table 307 is sequentially transferred by the robot 303, and immediately after the unexposed wafer 510 placed on the turntable 306 is transferred by the load arm 310, the turntable 306 is immediately transferred. Placed on.
Further, in the transfer operation of the wafer 500 to the wafer stage 210 by the load arm 310 and the unload arm 320, when the unload arm 320 carries out the exposed wafer 520 from the wafer stage 210, the load arm 310 already has the next unexposed light. The wafer 510 is placed, and the load arm 310 immediately stands by in a state where the unexposed wafer 510 can be loaded into the wafer stage 210.
In this way, the wafer loader system 300 of the exposure apparatus 10 carries the wafer 500 at a high speed so as to improve the throughput of the lot processing in the exposure apparatus 10.

  Next, the operation of the wafer loader system 300 according to the present invention in such an exposure apparatus 10 will be described with reference to FIGS. Specifically, the exchange operation of the wafer 500 on the wafer stage 210 via the load arm 310 and the unload arm 320 will be described.

FIGS. 2A to 2D and FIGS. 3A to 3D show the wafer stage 210, the upper and lower tables 220, the load arm 310, and the unload arm 320 when the wafer 500 is replaced. FIG. 2 is a view for sequentially explaining the movement, and when the exposure apparatus 10 shown in FIG. 1 is viewed in the −X direction of the X axis direction, a wafer stage 210, an upper and lower table 220, a load arm 310, an unload arm 320, and It is a figure which shows the relative positional relationship of the wafer 500 (Unexposed wafer 510 and exposed wafer 520) conveyed.
Hereinafter, from the state where the exposed wafer 520 is placed on the wafer stage 210, the exposed wafer 520 is unloaded, and a new unexposed wafer 510 is loaded and placed on the wafer stage 210. explain.

First, as shown in FIG. 2A, the unexposed wafer 510 is placed on the load arm 310, and the load arm 310 is moved to the wafer delivery position P1 in the upper space of the wafer stage 210.
Next, the upper and lower tables 220 are raised (moved in the + Z direction) as indicated by arrows in FIG. 2A, and the exposed wafer 520 is lifted from the wafer stage 210 as shown in FIG.
Next, the unload arm 320 is moved as shown by an arrow in FIG. 2B, and the unload arm 320 is moved to the wafer delivery place P1 in the upper space of the wafer stage 210 as shown in FIG. It is moved and inserted under the exposed wafer 520 (on the wafer stage 210 side).
In this state, the upper and lower tables 220 are lowered as indicated by arrows in FIG. 2C, and the exposed wafer 520 held on the upper and lower tables 220 is moved onto the unload arm 320 as shown in FIG. Placed on.

2D, the unload arm 320 on which the exposed wafer 520 is placed is retracted from the wafer delivery position P1 in the upper space of the wafer stage 210, and then the load arm 310 is moved. The upper and lower tables 220 are moved up to receive the unexposed wafer 510 placed on the substrate.
The relative positional relationship between the load arm 310 and the unexposed wafer 510, the unload arm 320 and the exposed wafer 520, and the upper and lower tables 220 at this time is from above the exposure apparatus 10 (from the Z-axis direction to the Z direction). FIG. 4 shows the state as seen.

In the wafer loader system 300 of this embodiment, as shown in FIGS. 3A and 4, the exposed wafer 520 placed on the unload arm 320 does not interfere with the upper and lower tables 220 that move in the vertical direction. When reaching P3, that is, the position P3 where the position does not overlap in the horizontal direction, the upper and lower tables 220 start to rise as indicated by arrows in FIG. As shown in FIG. 4, this position P3 is a position P4 where the exposed wafer 520 placed on the unload arm 320 does not interfere with the unexposed wafer 510 in the XY plane direction (unloading completion position, FIG. 9 (A), It is a position on the upper and lower table 220 side than (see FIG. 10).
Thereafter, the upper and lower tables 220 reach the position of the unexposed wafer 510 placed on the load arm 310 and lift and hold the unexposed wafer 510 from the load arm 310 as shown in FIG.

The unload arm 320 continues to move after passing through the position P3 and stops at the delivery position P5 of the exposed wafer 520.
FIG. 5 shows the movement state of the unload arm 320 from the wafer delivery position P1 in the upper space of the wafer stage 210 to the wafer delivery position P5 to the robot 303.
FIG. 5 is a diagram illustrating the moving speed of the unload arm 320 during the moving period.
As shown in FIG. 5, the unload arm 320 moves at a constant speed without stopping halfway from the position P1 to the position P5.
The unload arm 320 or the exposed wafer 520 passing or reaching the position P3 is detected by a sensor (not shown) provided in the wafer loader system 300.

  At the delivery position P5, the exposed wafer 520 placed on the unload arm 320 is delivered to the robot 303 of the wafer loader system 300. In addition, delivery of the exposed wafer 520 to the robot 303 is scheduled and performed in relation to the loading operation of the wafer 500 onto the wafer stage 210 and the transfer operation with the coater / developer. 3B to 3D, it is assumed that the exposed wafer 520 is maintained on the unload arm 320.

Next, as shown by an arrow in FIG. 3B, the load arm 310 is retracted from the upper space of the wafer stage 210, and then the unexposed wafer 510 placed on the upper and lower tables 220 is placed on the wafer stage 210. 3, the upper and lower tables 220 are lowered as indicated by arrows in FIG.
FIG. 6 shows the relative positional relationship between the load arm 310, the unexposed wafer 510, and the upper and lower tables 220 at this time, as viewed from above the exposure apparatus 10 (from the Z-axis direction-Z direction).
In the wafer loader system 300 of this embodiment, as shown in FIGS. 3C and 6, the load arm 310 does not interfere with the unexposed wafer 510 placed on the upper and lower tables 220 (note that this position P2 (P2 is the same position as the position P2 described in FIG. 9C and FIG. 12), that is, when the position reaches the position P2 where the position does not overlap in the horizontal direction, the load arm as described in FIG. The lower table 220 starts to descend as indicated by an arrow in FIG. 3C without temporarily stopping 310.
Thereafter, the upper and lower tables 220 continue to descend to the position of the stage surface of the wafer stage 210 and place the unexposed wafer 510 on the wafer stage 210 as shown in FIG.

On the other hand, the load arm 310 continues to move after passing through the position P2, and stops at the receiving position P6 of the next new unexposed wafer 510.
FIG. 7 shows the movement state of the load arm 310 from the wafer delivery position P1 in the upper space of the wafer stage 210 to the reception position P6 of the new unexposed wafer 510 from the robot 303.
FIG. 7 is a diagram illustrating the moving speed of the load arm 310 during the moving period.
As shown in FIG. 7, the load arm 310 moves at a constant speed in the section from the position P1 to the position P6 without stopping halfway (without stopping at the position P2).
The fact that the load arm 310 has passed the position P2 is detected by a sensor (not shown) provided in the wafer loader system 300.

  In the exposure apparatus 10 of the present embodiment, the wafer 500 on the wafer stage 210 is exchanged by the wafer loader system 300 by the operation as described above.

As described above, in the wafer loader system 300 of the exposure apparatus 10 of this embodiment, when the wafer 500 on the wafer stage 210 of the exposure apparatus main body 200 is replaced by the load arm 310 and the unload arm 320, the load arm 310 uses the wafer. The position where the exposed wafer 520 transferred to the unload arm 320 does not interfere with the unexposed wafer 510 (the fully retracted position) for the ascending operation of the upper and lower tables 220 for receiving the unexposed wafer 510 carried into the upper space of the stage 210 That is, the position where the exposed wafer 520 does not mechanically interfere with the vertical movement of the upper and lower tables 220 (predetermined retraction position P3) without waiting for the transfer to the unloading completion position P4) (see FIG. 9A). ) Immediately when it is transported to (see Fig. 3 (A)) . That is, the timing of the raising operation of the upper and lower tables 220 is advanced.
Therefore, the unexposed wafer 510 can be received earlier by the earlier time and placed on the wafer stage 210. That is, the wafer exchange time can be shortened by the earlier time.

Further, when detecting the timing for starting the ascending operation of the upper and lower tables 220, the unload arm 320 on which the exposed wafer 520 is placed and retracted is temporarily stopped and positioned to confirm the position (retraction confirmation). (See FIG. 11), the position confirmation is performed simply by detecting (see FIG. 5) that the unload arm 320 during the retreating movement has passed the detection position (predetermined retreat position P2). A trigger for starting the ascending operation of the upper and lower tables 220 is used. (The unload arm 320 is not temporarily stopped)
Therefore, a period in which the moving speed of the unload arm 320 is decelerated in order to stop the unload arm 320, a period in which the arm 320 is stopped, and a period in which the arm 320 is accelerated again to reach a constant speed are conventionally used. The extra time required is no longer required, and the upper and lower tables 220 are raised earlier by that time to receive the unexposed wafer 510 and place it on the wafer stage 210. That is, the wafer exchange time can be further reduced by this time.

Further, in the wafer loader system 300 of the present embodiment, the lowering operation of the upper and lower table 220 for placing the unexposed wafer 510 received from the load arm 310 on the wafer stage 210 is transferred to the upper and lower table 220. It starts when the load arm 310 is transported to a position (position P2 shown in FIGS. 3C and 6) that does not mechanically interfere with the unexposed wafer 510 placed on the upper and lower tables 220. At this time, the timing for starting the lowering operation of the upper and lower tables 220 is not to temporarily stop the load arm 310, perform positioning, check the position (see FIG. 13), and use it as a trigger. The position is confirmed simply by detecting that the load arm 310 has passed the position (see FIG. 7). It has been triggered by the.
Therefore, in order to stop and position the load arm 310, the conventionally required extra time of deceleration, stop, and acceleration period is unnecessary, and the upper and lower tables 220 are lowered earlier by that time to move the unexposed wafer 510 up and down. It can be placed on the table 220. That is, the wafer exchange time can be further reduced by this time.

  Further, in the exposure apparatus 10 of the present embodiment, as described above, information such as the ID, position, transport state, processing state or exposure state of each substrate of the lot being processed is sequentially displayed in the exposure apparatus 10. It is stored in a control unit (memory) not shown. Therefore, even when the apparatus is stopped due to some error or the like, when the power is turned off, when it is reset, etc., recovery can be performed quickly and in the best condition when the apparatus is restored.

In addition, this embodiment is described in order to make an understanding of this invention easy, and does not limit this invention at all. Each element disclosed in the present embodiment includes all design changes and equivalents belonging to the technical scope of the present invention, and various suitable modifications can be made.
For example, in the configuration of the exposure apparatus 10 shown in FIG. 1, the configuration of each part other than the load arm 310, the unload arm 320, the wafer stage 210, and the upper and lower tables 220 is limited to the configuration shown in FIG. It is not a thing and an arbitrary structure may be sufficient.
Further, in the present embodiment, the present invention has been described by exemplifying the case where the present invention is applied to a wafer loader system of an exposure apparatus that transports a wafer. However, for any apparatus that transports an arbitrary object by a similar mechanism. Thus, the present invention is applicable.

FIG. 1 is a view showing the arrangement of an exposure apparatus according to an embodiment of the present invention. FIG. 2 is a first diagram for explaining the wafer exchange operation in the wafer loader system of the exposure apparatus shown in FIG. FIG. 3 is a second diagram for explaining the wafer exchange operation in the wafer loader system of the exposure apparatus shown in FIG. FIG. 4 is a diagram illustrating a state in which the relative positional relationship of each component is viewed from the upper side of the plane at the time when the upper and lower tables illustrated in FIG. FIG. 5 is a diagram showing the relationship between time and speed regarding the unload arm retracting operation in the wafer loader system of the exposure apparatus shown in FIG. FIG. 6 is a diagram illustrating a state in which the relative positional relationship between the components is viewed from the upper side of the plane when the lowering of the upper and lower tables illustrated in FIG. 3C is started. FIG. 7 is a diagram showing the relationship between time and speed regarding the retracting operation of the load arm in the wafer loader system of the exposure apparatus shown in FIG. FIG. 8 is a first diagram for explaining a wafer exchange operation in a conventional wafer loader system. FIG. 9 is a second diagram for explaining the wafer exchange operation in the conventional wafer loader system. FIG. 10 is a diagram illustrating a state in which the relative positional relationship of each component is viewed from the upper side of the plane at the time when the upper and lower tables illustrated in FIG. 9A start to rise. FIG. 11 is a diagram showing the relationship between time and speed with respect to the unload arm retracting operation in the conventional wafer loader system. FIG. 12 is a diagram illustrating a state in which the relative positional relationship between the components is viewed from the upper side of the plane when the lowering of the upper and lower tables illustrated in FIG. 9C is started. FIG. 13 is a diagram showing a relationship between time and speed regarding the retracting operation of the load arm in the conventional wafer loader system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Exposure apparatus 100 ... Chamber 101 ... Exposure chamber 102 ... Loader room 103 ... Partition wall 200 ... Exposure apparatus main body 210 ... Wafer stage 220 ... Upper / lower table 300 ... Wafer loader system 301 ... X guide 302 ... Y guide 303 ... Robot 304, 305 ... carrier table 306 ... turntable 307 ... wafer transfer table 310 ... load arm (loading arm)
320 ... Unload arm (unload arm))
500 ... Wafer 510 ... Unexposed wafer 520 ... Exposed wafer

Claims (13)

A stage having a placement surface on which an object is placed;
An unloading arm for unloading an object to be unloaded from the mounting surface on the stage from the space above the stage to a unloading completion position outside the space above the stage;
The table is movable in a direction perpendicular to the placement surface, and the object to be carried placed on the placement surface is lifted from the placement surface into the space and delivered to the carry-out arm. A transfer device having a movable table,
The movable table starts to move in the vertical direction based on information indicating the state of unloading of the object by the unloading arm before the unloading arm completes the unloading operation of the object to the unloading completion position. A conveying device comprising a control means. A stage having a placement surface on which an object is placed;
A loading arm for loading an object to be placed on the placement surface on the stage into the space above the stage;
A transfer device having a movable table that is movable in a direction perpendicular to the placement surface and that receives an object transported into the space by the carry-in arm and places the object on the placement surface. Because
The vertical movement of the movable table without stopping the driving of the carry-in arm based on information indicating that the carry-in arm after delivering the object to the movable table is retreated from the space to the retreat completion position. A conveying device comprising control means for starting movement in a direction. A stage on which an object is placed;
A carry-in arm that conveys an object to be placed on a placement surface provided on the stage into a first space above the stage;
An unloading arm for unloading an object to be unloaded from the stage from the second space on the stage side of the stage above the first space to a unloading completion position outside the second space;
A table movable in a direction perpendicular to the placement surface, wherein the first object to be carried placed on the placement surface is lifted from the placement surface into the second space, and the carry-out is performed. A transfer device having a movable table that delivers the second object transferred into the first space by the carry-in arm and places the second object on the placement surface.
Based on information indicating the unloading state of the first object by the unloading arm before the unloading arm completes the unloading operation of the first object to the unloading completion position, or delivers the object to the movable table. The loading arm or the loading arm is driven based on the information indicating the retracted state of the loading arm before the loading arm completes the retreating operation from the first space to the retreat completion position. A conveying apparatus comprising a control unit that starts moving the movable table in the vertical direction without stopping.   The control means is placed on the carry-in arm based on information indicating that the first object that is placed on the carry-out arm has moved to a position where it does not mechanically interfere with the movable table. The transport apparatus according to claim 3, wherein the movable table is moved up along the vertical direction to receive the second object.   The control means moves the second object onto the placement surface based on information indicating that the carry-in arm has moved to a position where it does not mechanically interfere with the second object placed on the movable table. 5. The transport device according to claim 3, wherein the movable table is moved down along the vertical direction in order to place the movable table. 5. A sensor that detects that the object placed on the carry-out arm has passed through a position that does not interfere with the vertical movement of the movable table;
The transport device according to claim 1, wherein the control unit controls movement of the movable table based on an output of the sensor.   7. The unloading arm moves continuously to the unloading completion position without stopping until at least the passage of the position is detected by the sensor. The conveying apparatus as described. The carry-in arm further includes a sensor that detects that the movable table has passed through a position that does not interfere with an object placed on the movable table when the movable table moves in the vertical direction;
6. The transport apparatus according to claim 2, wherein the control unit controls movement of the movable table based on an output of the sensor.   The said carrying-in arm moves continuously without stopping until at least the passage of the position by the sensor is detected when moving to the retreat completion position. The conveying apparatus as described. A transport method for carrying out a first object placed on a placement surface on a stage from the placement surface, and carrying a second object onto the placement surface,
A first step of conveying the second object into a first space above the stage by a loading arm;
The first object is moved in a second space on the stage side of the stage above the first space by a table movable in a direction perpendicular to the mounting surface. Two steps,
While the first object existing in the second space is being unloaded by the unloading arm toward a predetermined unloading position outside the second space, the movable table is moved into the first space. The third step to start moving toward
A fourth step of transferring the second object from the transfer arm to the movable table in the first space;
After the fourth step, the movable table is moved without stopping the movement of the carry-in arm while the carry-in arm is moving from the first space toward a predetermined position outside the first space. Including a fifth step of starting movement toward the placement surface.   In the third step, when it is detected that the first object received by the carry-out arm has passed through a position that does not interfere with the movement of the movable table in the vertical direction, the movement of the movable table is started. The transport method according to claim 10.   In the fifth step, when it is detected that the carry-in arm has passed a position that does not interfere with the movement of the second object placed on the movable table in the vertical direction, the movement of the movable table The conveyance method according to claim 10 or 11, wherein the process is started.   10. An exposure apparatus for transferring an image of a pattern formed on a mask to a substrate via a projection optical system, wherein the transfer apparatus transfers at least one of the mask and the substrate to a stage. An exposure apparatus comprising the transport device according to claim 1.

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