JP2004128249A - Substrate holding and carrying method, device therefor, substrate holder, substrate carrying device, and aligner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate holding and carrying method etc., capable of stably holding a substrate while performing the elevating and lowering work of the substrate and the putting-in and putting-out work of an end effector with one mechanism. <P>SOLUTION: A substrate holding and carrying device 1 comprises a substrate holder 10 and a substrate carrying device 20. The end effector 25 of the substrate carrying device 20 is equipped with a two-pronged arm 27 having a substrate support 29 supporting an edge of the substrate. A suction carrier 11 of the substrate holder 10 has a suction surface 13 which sucks nearly the entire surface of the substrate, an entry groove 15 for end effector which is dug in the suction surface 13 along an end surface of the suction carrier, and a notch 17 which communicates with the suction surface from the entry groove and through which the substrate support 29 of the end effector can pass. The substrate support part 29 passes through the groove 15 and the notch 17, and abuts against the edge of the substrate at three places from below to elevate and carry the substrate. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for holding and transporting a substrate (sensitive substrate, wafer) of a semiconductor exposure apparatus.
[0002]
[Prior art]
In the exposure apparatus, the sensitive substrate (wafer) is transferred from the wafer storage chamber to the stage by the transfer robot and exposed, and after the exposure, is transferred from the stage to the wafer storage chamber by the robot. On the stage, the entire surface of the substrate is sucked and held by the suction surface of the holder. At the center of the holder, a plurality of pins that move up and down are provided. When removing the substrate from the holder, the suction force (vacuum or electrostatic force) is released, and then the pins are raised to lift the substrate above the suction surface of the holder (center-up method). Then, the end effector of the transfer robot is caused to enter the lower surface of the substrate, and the substrate is held by the end effector. Then, the pins are lowered to transfer the substrate to the end effector. Thereafter, the end effector is moved to transfer the substrate to the storage room. When transferring the substrate from the storage chamber to the holder, the procedure is reversed.
[0003]
As a method of transferring the substrate from the holder to the end effector, besides the center-up method, there is also a method of transferring the substrate from the end effector to the upper surface of the holder by a transfer device installed above the holder (elevator method).
[0004]
[Problems to be solved by the invention]
In the above method, the operation of raising and lowering the substrate on the holder and the operation of putting the end effector under and out of the substrate must be performed in a series as a series of operations, thus reducing the throughput. Further, since two mechanisms, ie, a mechanism for raising and lowering the substrate and a mechanism for taking in and out the end effector, are required, there is a problem that the apparatus and the working space are enlarged, and the cost is increased.
Further, in the center-up system or the elevator system, a driving device (a motor or the like) for driving a pin or a transport device must be installed below a holder in the exposure apparatus. For this reason, when a magnetic field affects exposure as in an EB exposure apparatus, it is necessary to provide a means for preventing leakage of the magnetic field from the driving device.
[0005]
On the other hand, there is a method in which a substrate is transferred to a holder and directly delivered. In this method, the size of the suction surface of the holder is made smaller than the size of the substrate so that the holder does not interfere with the end effector. That is, the peripheral portion of the substrate protrudes outside the holder. For this reason, the effective suction area of the suction surface is reduced, so that the entire surface of the substrate cannot be suctioned, and the suction force is weakened. Then, the surface of the substrate that is not adsorbed by the holder is warped, and the substrate may be deformed.
[0006]
The present invention has been made in view of the above problems, and provides a substrate holding / transporting method and the like that can perform a substrate raising / lowering operation and an end effector loading / unloading operation with a single mechanism, and can stably hold a substrate. The purpose is to:
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the substrate transfer and holding method according to the present invention is characterized in that a groove is dug below the suction surface along an end surface of a suction disk of a substrate holder, and a notch communicating from the groove to the suction surface is provided. The substrate is held by holding the substrate by suction on almost the entire suction surface of the suction plate of the substrate holder, and the substrate support portion of the end effector is applied to the three edge portions of the substrate from below through the grooves and cutouts to thereby lower the substrate. Is lifted and transported.
Since the substrate can be held by the end effector and transferred directly to the holder, the transfer and transfer operations of the substrate can be performed in a series of operations, and the operation time can be reduced. Further, since the end effector can be taken in and out of the suction plate even while the substrate is being held, the work time can be shortened by that much time. Furthermore, since the substrate is almost entirely held by the substrate holder, deformation such as warpage hardly occurs.
[0008]
The substrate holder of the present invention is a substrate holder provided with a suction plate for sucking a substrate to be held, wherein the suction plate has a suction surface for sucking substantially the entire surface of the substrate and an end surface of the suction plate. And an entrance groove of the end effector of the substrate transfer robot dug under the suction surface, and a substrate support portion of the end effector cut out so as to communicate with the suction surface from the entrance groove. And a notch.
The end effector does not interfere with the suction surface of the holder because the end effector penetrates the intrusion groove dug below the suction surface along the end surface of the suction plate. The size of the suction surface that can be suctioned is substantially the entire suction surface except for a cutout portion that leads to the suction surface through which the substrate support passes. Therefore, a sufficient substrate suction area can be secured, the suction force of the substrate on the suction surface does not decrease, and deformation such as warpage of the held substrate hardly occurs. Further, since the substrate is transferred to the substrate holder by the end effector, there is no need to provide a function of elevating the substrate.
A substrate transfer device according to the present invention is a substrate transfer device including an end effector having three or more substrate support portions that support an edge portion of a substrate to be transferred, wherein the substrate support portions each have a tip portion. Wherein the profile of the inner edge of the forked arm is formed larger than the outer edge of the substrate.
Since the edge of the substrate is supported at three or more locations, the substrate can be stably held and transported.
[0010]
A substrate holding and transporting device of the present invention is a device for holding and transporting a substrate, comprising: a substrate holder for holding the substrate; and a substrate transporting device for transporting the substrate, wherein the substrate holder transfers the substrate. A suction surface for sucking substantially the entire surface of the substrate; and an end effector of the substrate transfer robot dug under the suction surface along an end surface of the suction plate. An intrusion groove, and a notch cut out so as to communicate with the suction surface from the intrusion groove and through which a substrate supporting portion of the end effector can pass. An end effector having three or more substrate support portions for supporting the substrate, wherein each of the substrate support portions has a bifurcated end effector arm formed at a distal end thereof, and an inner edge of the bifurcated arm. No The fill is formed larger than the outer edge of the substrate, and the substrate is supported by lifting the substrate by applying the substrate support portion of the end effector to three places on the edge of the substrate from below through the grooves and notches. Features.
[0011]
An exposure apparatus according to the present invention is an exposure apparatus that selectively irradiates a sensitive substrate with an energy beam to form a pattern, and includes the substrate holding / transporting device described above.
The substrate can be held on the holder without being deformed, and can be stably transported. Further, since the delivery and transfer operations of the substrate can be performed by a series of operations, the throughput of the exposure operation is improved. Further, there is no need to provide a new mechanism or device, and the device does not increase in size. In addition, since a mechanism for generating a magnetic field is not provided for transferring the substrate, the present invention can be applied to a case where an energy ray which is easily affected by the magnetic field is used.
The type of the energy ray is not particularly limited, and light, ultraviolet light, X-ray, electron beam, ion beam, and the like can be applied. Further, the exposure transfer method is not particularly limited, and a reduction projection method, a close-to-uniform transfer method, or the like can be applied.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, description will be made with reference to the drawings.
FIG. 1 is a view for explaining the structure of a substrate carrying and holding apparatus according to an embodiment of the present invention, wherein FIG. 1 (A) is a plan view and FIG. 1 (B) is a partial cross-sectional front view.
FIG. 2 is a diagram for explaining the overall structure of the substrate carrying and holding apparatus according to the embodiment of the present invention.
As shown in FIG. 2, the substrate transfer and holding device 1 includes a substrate holder 10 and a substrate transfer device 20. The substrate holder 10 is set on a wafer stage 131 in a wafer chamber 121 of the exposure apparatus. The substrate transfer device 20 transfers the substrate W between the substrate storage chamber 141 in the device and the substrate holder 10 on the wafer stage 131, and transfers the substrate W to the holder 10.
[0013]
First, the structure of the substrate transfer device 20 will be described.
As shown in FIG. 2, the substrate transfer device 20 is a transfer robot including a base 21 and a plurality of arms 23 connected so as to perform articulation. The most proximal arm 23 is attached to the base 21 for articulation and for moving up and down. The end arm 23 is provided with an end effector 25. The end effector 25 can rotate in the XY plane and move in the Z direction.
[0014]
The end effector 25 is branched at its tip into a bifurcated arm 27. As shown in FIG. 1 in an enlarged manner, the shapes of both arms 27 are symmetrical, and the profiles of the inner edges of both arms 27 are circular. The size of this profile is larger than the size of the sensitive substrate W. Substrate support portions 29 protruding inward are provided at three locations at the arm branch point and the tip of each arm 27. The substrate supporting portion 29 has a circular or semicircular planar shape, and has the same thickness as the end effector 25 and each arm 27. Each substrate supporting portion 29 is disposed at substantially the same central angle (about 120 °) with respect to the center of the circular profile of the inner edge of both arms 27. The edge of the substrate W is supported on the upper surface of the substrate support 29.
[0015]
Next, the structure of the substrate holder 10 will be described.
As shown in FIG. 1, the substrate holder 10 includes a suction plate 11 that sucks and holds the sensitive substrate W. The suction disk 11 has a disk shape, a planar shape that is the same circle as the shape of the sensitive substrate W, and a diameter substantially equal to the diameter of the sensitive substrate W. The upper surface of the suction disk 11 is a suction surface 13 for sucking almost the entire surface of the substrate W. A voltage is applied to the suction surface 13 to electrostatically suction and hold the back surface of the substrate W. Note that a vacuum chuck can be used in an air atmosphere or the like.
[0016]
On the side wall of the suction disk 11, two entry grooves 15 for entering the end effector arm 27 described above are formed. Each intrusion groove 15 is formed by digging a predetermined thickness from the side wall on both sides of the suction plate 11 below the suction surface 13 inward of the plate. As shown in FIG. 1B, each of the intrusion grooves 15 extends parallel to the suction surface 13 in the thickness direction of the suction disk 11. As shown in FIG. 1A, the suction plates 11 are arranged symmetrically with respect to a line L passing through the center of the suction surface 13 in the plane direction of the suction plate 11. The back wall of each groove is parallel and traverses the suction cup 11 straight. The space between the inner walls of the left and right grooves 15 is slightly smaller than the space between the substrate support portions 29a at the end of the end effector arm. The thickness of each entry groove 15 is slightly larger than the thickness of the end effector arm 27. The end effector 25 enters along the longitudinal direction of the entry groove 15.
[0017]
Further, the suction disk 11 is provided with three notches 17 through which the substrate support portion 29 of the end effector arm 27 passes in the vertical direction (Z direction). The planar shape of the notch 17 is slightly larger than the shape of the substrate support 29. Each notch 17 is disposed at a substantially equal center angle (about 120 °) with respect to the center of the suction disk 11. The two cutouts 17a are located at positions substantially corresponding to the substrate holding portions 29a at the distal end of the end effector arm, and are formed so as to communicate with the suction surface 13 from each of the intrusion grooves 15. I have. The other notch 17b is located at a position on the center line L of the suction plate 11 corresponding to the substrate holding portion 29b of the arm branch portion, and extends from near the center in the thickness direction of the suction plate 11 to the suction surface 13. It is formed to communicate.
[0018]
The operation of the substrate holding and transporting device 1 will be described.
First, a case where the substrate W is transferred from the storage chamber 141 to the substrate holder 10 on the wafer stage 131 will be described. First, the substrate W is transferred from the storage chamber 141 onto the substrate support portion 29 of the end effector 25 of the substrate transfer device 1. This operation is the same as the conventional operation. Then, the arm 23 is moved in the XY plane, and the end effector 25 holding the substrate W is moved from the storage chamber 141 to just above the substrate holder 10. At this time, the end effector 25 and the substrate holder 10 are arranged such that the held substrate W and the suction surface 13 of the substrate holder 10 overlap with each other in a plane, and the substrate support portions 29 of the end effector 25 correspond to the corresponding suction plates 11. It is positioned so as to overlap the notch 17.
[0019]
Thereafter, the arm 23 is moved in the Z direction, and the end effector 25 is lowered directly below. Each substrate support portion 29 of the end effector arm 27 passes through the corresponding notch 17 of the suction disk 11, and the substrate W is transferred onto the suction surface 13 of the suction disk 11 in the middle of this. The end effector 25 descends until it reaches the height of the entry groove 15. Then, the end effector 25 is moved so as to be pulled downward in FIG. 1A and passes through the intrusion groove 15 to move the end effector 25 away from the substrate holder 10 and return to the standby position.
When the substrate W is transferred onto the suction surface 13 of the substrate holder 10, a voltage is applied to the suction surface 13, and the substrate W is sucked and held on the same surface by electrostatic force. The size of the suction surface 13 is substantially the same as the size of the substrate W except for the three cutouts 17, and the suction force is secured because almost the entire surface of the substrate W is suctioned and held. No warping occurs.
[0020]
Such an operation requires less operation than the conventional substrate transfer operation (center-up method). That is, the center-up type substrate transfer operation includes (1) raising the pins of the substrate holder to the substrate receiving position, (2) moving the end effector holding the substrate to the upper part of the pins, and transferring the substrate onto the pins. And (3) returning the end effector, and (4) lowering the pin to move the substrate onto the suction surface.
On the other hand, the transfer operation of the substrate holding and transporting device of the present invention includes: (1) moving the end effector holding the substrate to the upper part of the suction surface; (2) lowering the end effector to move the substrate onto the suction surface; (3) Returning the end effector only requires three operations. Therefore, the substrate transfer time can be reduced. The operation of returning the end effector (taken out of the suction plate) in (3) can be performed in parallel (simultaneously) with other steps, so that the exposure time can be subtracted from the tact time of substrate handling.
[0021]
Next, a case where the substrate W is received from the substrate holder 10 to the end effector 25 will be described. First, the arm 23 is operated to position the end effector 25 at a position matching the entry groove 15 of the suction board 11. Then, the arm 23 is moved, and the end effector is advanced in the upward direction in FIG. 1 (A), and the end effector 25 is inserted into the entry groove until the respective substrate supporting portions 29 reach the positions where they overlap the notches 17 of the corresponding suction disks 11. 15 inside. Thereafter, the application of the voltage to the suction surface 13 of the suction disk 11 is stopped, and the electrostatic force between the substrate W and the suction surface 13 is released.
[0022]
Then, the arm 23 is moved in the Z direction, and the end effector 25 is raised directly above. The substrate support portion 29 of the end effector arm 27 passes through the notch 17 of the suction disk 11, and the substrate W is transferred onto the substrate support portion 29 on the way. Thereafter, the end effector 25 is raised above the suction surface, and the arm 23 is rotated in the XY plane to transfer the substrate W to the substrate storage chamber 141.
[0023]
This substrate receiving operation can be performed with less operation than the conventional method. In each operation, the transfer of the substrate W to the suction surface 13 is performed by the end effector 25 (transfer device 20), and there is no need to provide a device for lifting and lowering the substrate on the wafer stage 131.
[0024]
FIG. 3 is a diagram schematically illustrating the configuration of the exposure apparatus according to the embodiment of the present invention.
An optical lens barrel 101 is disposed above the electron beam exposure apparatus 100. A vacuum pump (not shown) is installed in the optical barrel 101, and the inside of the optical barrel 101 is evacuated.
[0025]
An electron gun 103 is disposed above the optical barrel 101 and emits an electron beam downward. Below the electron gun 103, an illumination optical system 104 including a condenser lens 104a, an electron beam deflector 104b, and the like are arranged in this order. A reticle R is disposed below the lens barrel 104.
The electron beam emitted from the electron gun 103 is converged by the condenser lens 104a. Subsequently, the light is sequentially scanned (scanned) in the horizontal direction in the figure by the deflector 104b, and illumination of each small area (subfield) of the reticle R within the field of view of the optical system is performed. Although the condenser lens 104a has one stage in the drawing, the actual illumination optical system is provided with several stages of lenses, a beam shaping aperture, a blanking aperture, and the like.
[0026]
Reticle R is fixed to chuck 110 provided on reticle stage 111 by electrostatic attraction or the like. The reticle stage 111 is mounted on a surface plate 116.
[0027]
The reticle stage 111 is connected to a driving device 112 shown on the left side of the figure. Actually, the driving device (linear motor) 112 is incorporated in the stage 111. The driving device 112 is connected to a control device 115 via a driver 114. A laser interferometer 113 is provided on the side (right side in the figure) of the reticle stage 111. The laser interferometer 113 is also connected to the control device 115. Accurate positional information of the reticle stage 111 measured by the laser interferometer 113 is input to the control device 115. A command is sent from the control device 115 to the driver 114 so that the position of the reticle stage 111 is set as the target position, and the driving device 112 is driven. As a result, the position of the reticle stage 111 can be accurately feedback-controlled in real time.
[0028]
A wafer chamber (vacuum chamber) 121 is arranged below the surface plate 116. A vacuum pump (not shown) is connected to the side of the wafer chamber 121 (right side in the figure), and the inside of the wafer chamber 121 is evacuated.
A projection optical system 124 including a condenser lens (projection lens) 124a, a deflector 124b, and the like is arranged in the wafer chamber 121 (actually, in an optical barrel in the chamber). A wafer (sensitive substrate) W is arranged in a lower part in the wafer chamber 121.
[0029]
The electron beam that has passed through the reticle R is converged by the condenser lens 124a. The electron beam that has passed through the condenser lens 124a is deflected by the deflector 124b, and an image of the reticle R is formed at a predetermined position on the wafer W. Although the condenser lens 124a has one stage in the drawing, in practice, a plurality of stages of lenses, aberration correcting lenses and coils are provided in the projection optical system.
[0030]
The wafer W is held by being held by an electrostatic force on the holder 10 (see FIG. 1, the suction surface 13 shown in FIG. 1) provided above the wafer stage 131. The wafer W is transferred to the substrate transfer device 20 (see FIGS. 1 and 2). ), The wafer is transferred between the wafer storage chamber 141 and the holder 10 of the wafer stage 131. The wafer stage 131 is placed on the surface plate 136.
[0031]
A driving device 132 shown on the left side of the drawing is connected to the wafer stage 131. Note that the driving device 132 is actually incorporated in the stage 131. The driving device 132 is connected to the control device 115 via a driver 134. A laser interferometer 133 is provided on the side of the wafer stage 131 (right side in the figure). The laser interferometer 133 is also connected to the control device 115. The accurate position information of the wafer stage 131 measured by the laser interferometer 133 is input to the control device 115. A command is sent from the control device 115 to the driver 134 so that the position of the wafer stage 131 is targeted, and the driving device 132 is driven. As a result, the position of the wafer stage 131 can be feedback-controlled accurately in real time.
[0032]
【The invention's effect】
As is apparent from the above description, according to the present invention, the substrate is held and transported by the end effector, and is directly transferred onto the holder. It can be carried out. For this reason, the transport time can be reduced, and the throughput can be improved. Further, the substrate can be stably held without being deformed. Further, since there is no need to provide a driving device for transferring the substrate in the vicinity of the stage, the device is simplified, and there is no need to deal with leakage of the magnetic field.
[Brief description of the drawings]
FIG. 1 is a view for explaining a structure of a substrate carrying and holding apparatus according to an embodiment of the present invention, wherein FIG. 1 (A) is a plan view and FIG. 1 (B) is a partial cross-sectional front view.
FIG. 2 is a diagram for explaining the overall structure of the substrate carrying and holding apparatus according to the embodiment of the present invention.
FIG. 3 is a diagram schematically illustrating a configuration of an exposure apparatus according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Substrate transfer holding device 10 Substrate holder 11 Suction board 13 Suction surface 15 Intrusion groove 20 Substrate transfer device 21 Base 23 Arm 25 End effector 27 Arm 29 Substrate support 17 Notch 100 Electron beam exposure apparatus 101 Optical lens barrel 103 Electron gun 104 Illumination optical system 110 Chuck 111 Reticle stage 112 Drive unit 113 Laser interferometer 114 Driver 115 Control unit 116 Surface plate 121 Wafer chamber 124 Projection optical system 131 Wafer stage 132 Drive device 133 Laser interferometer 134 Driver 136 Surface plate 141 Substrate accommodation room

Claims (5)

A groove is dug below the suction surface along the end surface of the suction plate of the substrate holder, and a cutout communicating from the groove to the suction surface is provided,
While holding the substrate by suction on almost the entire suction surface of the suction plate of the substrate holder,
A substrate holding / transporting method, wherein the substrate is lifted and transported by applying the substrate support portion of the end effector to three locations on the edge of the substrate from below through the grooves and notches. A substrate holder including a suction plate that suctions a substrate that is a holding target,
The suction cup,
An adsorption surface that adsorbs substantially the entire surface of the substrate;
Along the end surface of the suction disk, dug below the suction surface, an entry groove of an end effector of the substrate transfer robot,
A notch that is cut out from the intrusion groove to communicate with the suction surface, through which a substrate supporting portion of the end effector can pass;
A substrate holder comprising: A substrate transport device including an end effector having three or more substrate support portions that support an edge of a substrate to be transported,
The substrate supporting portion has a bifurcated end effector arm formed at a distal end thereof,
A substrate transfer device, wherein a profile of an inner edge of the bifurcated arm is formed larger than an outer edge of the substrate. An apparatus for holding and transporting a substrate,
It comprises a substrate holder for holding the substrate, and a substrate transfer device for transferring the substrate,
The substrate holder includes a suction plate that suctions the substrate,
The suction cup,
An adsorption surface that adsorbs substantially the entire surface of the substrate;
Along the end surface of the suction disk, dug below the suction surface, an entry groove of an end effector of the substrate transfer robot,
A notch that is cut out from the intrusion groove to communicate with the suction surface, through which a substrate supporting portion of the end effector can pass;
Has,
The substrate transfer device includes an end effector having three or more substrate support portions that support an edge of the substrate,
The substrate supporting portion has a bifurcated end effector arm formed at a distal end thereof,
An inner edge profile of the bifurcated arm is formed larger than an outer edge of the substrate;
A substrate holding and transporting device, wherein the substrate is lifted and transported by applying the substrate support portion of the end effector to three locations on the edge of the substrate from below through the groove and the notch. An exposure apparatus that selectively irradiates an energy beam onto a sensitive substrate to form a pattern,
An exposure apparatus comprising the substrate holding / transporting device according to claim 4.

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