JP2004071925A - Substrate loader and exposure device - Google Patents

Abstract

A substrate loader capable of handling an end effector at a high speed, and an exposure apparatus including the substrate loader are provided.
A fine movement rotary motor such as an ultrasonic motor or an air motor is attached to a second arm tip shaft of a substrate loader. The motor 110 makes the third arm 120 minutely rotate around the second arm tip axis P3. The rotation motor 110 rotates in a direction opposite to the direction of rotation of the third arm 120 by the rotation mechanism, and dynamically cancels residual vibration due to rotation of the rotation mechanism.
[Selection diagram] FIG.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate loader improved to suppress vibration and improve high-speed handling performance, and an exposure apparatus provided with the loader.
[0002]
[Prior art]
First, an outline of an exposure apparatus such as a semiconductor device will be described using an electron beam exposure apparatus as an example.
FIG. 14 is a diagram showing an outline of an imaging relationship and a control system in the entire optical system of the projection exposure type electron beam exposure apparatus.
An illumination optical barrel 201 is arranged above the electron beam exposure apparatus 200. A vacuum pump (not shown) is connected to the optical barrel 201 to evacuate the inside of the barrel.
[0003]
An electron gun 203 is disposed above a lens barrel (including a mask chamber) 201 and emits an electron beam downward. Below the electron gun 203, a condenser lens 204, an electron beam deflector 205, and a mask M are arranged in this order. The electron beam emitted from the electron gun 203 is converged by the condenser lens 204 and is sequentially scanned in the horizontal direction in the figure by the deflector 205, and each small area (subfield) of the mask M in the field of view of the optical system. Lighting is performed. The illumination optical system also has a beam shaping aperture, a blanking aperture, and the like (not shown).
[0004]
The mask M is fixed to a chuck 210 provided above the mask stage 211 by electrostatic attraction or the like. The mask stage 211 is mounted on the mount body 216.
[0005]
The drive unit 212 shown on the left side of the figure is connected to the mask stage 211. The driving device 212 is connected to the control device 215 via the driver 214. Further, a laser interferometer 213 shown on the right side of the figure is installed on the mask stage 211. The laser interferometer 213 is connected to the control device 215. The accurate position information of the mask stage 211 measured by the laser interferometer 213 is input to the control device 215. Based on this, a command is sent from the control device 215 to the driver 214, and the drive device 212 is driven.
[0006]
Below the mount body 216, a wafer chamber 206 (vacuum chamber) is shown. A vacuum pump (not shown) is connected to the wafer chamber 206 to evacuate the chamber.
A projection lens 224, a deflector 225, and the like are arranged in a projection optical system barrel (not shown) in the wafer chamber 206. Further, a wafer stage (precision equipment) 231 is mounted on the bottom surface of the wafer chamber 206 below the wafer stage 206. A chuck 230 is provided above the wafer stage 231, and the wafer W is fixed by electrostatic attraction or the like.
[0007]
The electron beam that has passed through the mask M is converged by the projection lens 224. The electron beam converged by the lens 224 is deflected by the deflector 225 to form an image of the mask M at a predetermined position on the wafer W. The projection optical system also has various aberration correction lenses and contrast apertures (not shown).
[0008]
The drive unit 232 shown on the left side of the figure is connected to the wafer stage 231. The driving device 232 is connected to the control device 215 via the driver 234. Further, a laser interferometer 233 shown on the right side of the figure is installed on the wafer stage 231. The laser interferometer 233 is connected to the control device 215. The accurate position information of the wafer stage 231 measured by the laser interferometer 233 is input to the control device 215. Based on this, a command is sent from the control device 215 to the driver 234, and the drive device 232 is driven.
[0009]
FIG. 15 is a plan view schematically illustrating a wafer transfer mechanism in a general wafer chamber.
In the wafer chamber 206, a wafer stocker 261 accommodating a plurality of preprocessed wafers and a wafer loader 250 are arranged. The wafer is transferred from the wafer stocker 261 to the wafer stage 231 by the loader 250, placed on the stage 231 and subjected to exposure transfer. The loader 250 includes an arm rotatably connected.
[0010]
In the loader 250 as described above, the wafers are transferred one by one from the wafer stocker 261 to the wafer stage 231 by the end effector provided on the arm. Also, when the image is returned from the mask stage 231 to the mask stocker 261 after the end of the transfer, the sheets are transported one by one.
[0011]
When the substrate loader operates at a high speed, the positioning accuracy and the settling time of the end effector deteriorate. This is because the rigidity of the mechanical part of the substrate loader cannot be increased, and the vibration becomes intense at high-speed operation. On the other hand, the residue between the actual sample position and the target position is obtained, and the end effector is positioned based on this value. The end effector is positioned by a rotary encoder provided in a joint of an arm having the end effector and a micro rotary motor as a driving source. First, the rotation angle of the arm is detected by a rotary encoder, and the position of the sample on the end effector is determined from the rotation angle. In this case, generally, a detection cycle of about five times the natural frequency of the mechanism is required. Then, the fine movement amount is calculated from the deviation between the actual sample position and the target position, a command is given to the minute rotation motor, and the detected rotation angle is fed back.
[0012]
[Problems to be solved by the invention]
The arm provided with the end effector, which is located at the most distal end of the substrate loader, vibrates minutely due to movement or rotation, and it is necessary to wait until the vibration stops, during which time the wafer cannot be transferred. For this reason, the throughput of the device decreases.
[0013]
The present invention has been made in view of the above problems, and has as its object to provide a substrate loader capable of handling an end effector at high speed, an exposure apparatus including the substrate loader, and the like.
[0014]
[Means for Solving the Problems]
In order to solve the above problems, a substrate loader of the present invention includes: a substrate mounting arm; a mechanism for extending the arm; a mechanism for elevating and lowering the arm; and an electromagnetic rotary motor that is an integrated drive source of the two mechanisms; The substrate loader further comprises: a fine rotation mechanism for rotating the substrate mounting arm.
A fine rotation mechanism is provided on the substrate mounting arm (end effector) to dynamically cancel residual vibration generated by rotation of the substrate mounting arm. For this reason, it is not necessary to wait until the minute vibration of the arm stops, and the throughput of the apparatus is improved.
[0015]
In the present invention, if the fine movement rotating mechanism has an actuator such as an ultrasonic motor or an air motor that does not generate a disturbance magnetic field, there is no leakage of magnetism from the mechanism, and the exposure accuracy is not affected.
Leakage can be blocked.
[0016]
An exposure apparatus according to the present invention is an exposure apparatus comprising: a sensitive substrate transport system; and an optical system that selectively irradiates the sensitive substrate with energy rays to form a device pattern on the sensitive substrate. A substrate transport system includes any one of the substrate loaders described above.
Since the substrate mounting arm (end effector) can be handled at high speed, there is no need to wait until the minute vibration generated by the rotation and movement of the arm stops. Therefore, an exposure apparatus with high throughput can be provided. The energy beam for exposure is not particularly limited, and ultraviolet light, X-ray, electron beam, ion beam, or the like can be used. The method of exposure is not particularly limited, and the present invention can be applied to reduction projection, close-to-uniform transfer, direct drawing, and the like.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, description will be made with reference to the drawings. In addition, each drawing is a schematic one, and for example, there is a case where an assembly of separate members is represented as an integral member.
FIG. 1 is a sectional perspective view showing the entire structure of the substrate loader according to the embodiment of the present invention.
FIG. 2 is an enlarged sectional perspective view showing the structure of the motor unit of the substrate loader of FIG.
FIG. 3 is a front sectional view of the motor unit of FIG.
FIG. 4 is an enlarged sectional perspective view showing the structure of the first arm of the substrate loader of FIG.
FIG. 5 is an enlarged sectional perspective view showing the structure of the second arm and the third arm of the substrate loader of FIG.
FIG. 6 is a sectional view schematically illustrating the structure of the mass balancer of the substrate loader of FIG.
[0018]
As shown in FIG. 1, the substrate loader 1 includes a motor unit 10 disposed in a casing 11, a first arm 80 connected to the unit 10 by a first joint 81, a first arm 80 and a second arm 80. It includes a second arm 100 connected by a joint 101, and a third arm 120 connected to the second arm 100 by a third joint 121. End effectors 125 are provided at both ends of the third arm 120. A semiconductor wafer is placed on the end effector 125 and transported.
[0019]
As shown in FIG. 1, the casing 11 includes a main body portion 17 including a cylindrical side wall 13 and a bottom wall 15, and a ceiling portion 19. The bottom wall 15 of the main body portion 17 includes a central portion 15a on a concentric circle, an intermediate portion 15b around the central portion, and an outermost portion 15c around the intermediate portion, and includes a central portion 15a, an intermediate portion 15b, and an outermost portion 15c. The steps are in order of height.
[0020]
First, the configuration of each arm will be described.
The first arm 80 is driven by a hollow first arm drive shaft 23 near the center of the motor unit 10. The second arm 100 is driven by a second arm drive shaft (belt pulley drive shaft) 21 at the center of the motor unit 10. The two shafts 23 and 21 are driven by separate motor mechanisms in the motor unit 10 and independently rotate about the axis P1 (details will be described later). The third arm 120 is driven by the second arm drive shaft 21 so as to rotate in the opposite direction by the same angle as the second arm 100. The third arm 120 is minutely driven by another motor at the base end of the third arm 120 (details will be described later).
[0021]
As shown in FIGS. 2 and 3, the motor unit 10 includes a second arm drive shaft 21 that rotates about the same axis P <b> 1 and a cylindrical first arm drive shaft 23. The second arm drive shaft 21 has a solid cylindrical shape, and the first arm drive shaft 23 has a substantially cylindrical shape, and is coaxial and concentric so as to fit around the outer periphery of the second arm drive shaft 21. Are located. A bearing 35 is interposed between the first arm drive shaft 23 and the ceiling 19 of the casing.
[0022]
The structure around the first arm 80 will be described with reference to FIG.
The base end of the first arm 80 is fixed to the first arm drive shaft 23. When the first arm drive shaft 23 rotates, the first arm 80 rotates around the central axis P1 (first joint 81) of the first arm drive shaft 23. A belt drive pulley 27 fixed to the second arm drive shaft 21 is disposed at a base end in the first arm 80, and a pulley 83 is disposed at a distal end in the arm 80. The first arm tip pulley 83 is rotatably attached to a shaft 85 fixed to the tip of the first arm 80 via a bearing 87. A belt 89 is wound between the two pulleys.
The rotation of the belt driving pulley 27 centered on the motor is transmitted to the first arm tip pulley 83 by the belt 89, and the pulley 83 rotates about the base axis P <b> 2 of the second arm 100. A second arm drive shaft 88 is fixed to the first arm tip pulley 83. The coaxial 88 rotates with the pulley 83 around the axis P2.
[0023]
The base end of the second arm 100 is fixed to the second arm drive shaft 88. When the second arm drive shaft 88 rotates, the second arm 100 rotates around the base axis P2 (the second joint 101). That is, by rotating the second arm drive shaft 21 in the motor, the second arm 100 rotates around the axis P2 at the tip of the first arm 80.
[0024]
Next, the structure of the second arm 100 and the third arm 120 will be described with reference to FIG.
A pulley 103 fixed to the first arm distal shaft 85 is disposed at a base end in the second arm 100, and a pulley 105 is disposed at a distal end in the arm 100. The second arm tip pulley 105 is rotatably attached to a shaft 107 fixed to the tip of the second arm 100 via a bearing 111. A belt 109 is wound between the two pulleys.
[0025]
The second arm proximal pulley 103 is fixed to the first arm distal shaft 85. Here, when the second arm 100 rotates with respect to the first arm 80, the second arm base end pulley 103 rotates relatively in the opposite direction. It is conveyed to 105.
[0026]
That is, in FIG. 5, when the belt 89 moves in the direction of the arrow in the figure, the first arm tip pulley 83 rotates clockwise, and the second arm 100 rotates in the direction of the arrow (clockwise) in the figure. However, the second arm base pulley 103 does not rotate because it is fixed to the first arm 80. Therefore, the belt 109 moves in the direction of the arrow in the figure, rotates the second arm tip pulley 105 in the counterclockwise direction, and the third arm 120 rotates in the direction of the arrow in the figure (counterclockwise). That is, the third arm 120 rotates in a direction opposite to that of the second arm 100. After all, since the third arm 120 rotates by the same angle in the direction opposite to the rotation direction of the second arm 100, the relative angle of the third arm 120 to the motor unit 10 does not change.
[0027]
A rotary encoder (not shown) for rotating the third arm 120 is incorporated in the second arm tip shaft 107. The rotary encoder detects the rotation angle of the third arm 120 at the third joint 121, and calculates the position of the sample on the end effector 125 from the detected rotation angle. Then, the fine movement amount is calculated from the deviation between the actual sample position and the target position. The calculated fine movement amount is fed back to the rotation mechanism, and the third arm 120 is positioned at the target position.
[0028]
A fine movement rotary motor 110 is further attached to the second arm tip shaft 107. The motor 110 makes the third arm 120 minutely rotate around the second arm tip axis P3. As the rotation motor 110, an ultrasonic motor or an air motor that does not use a coil or a magnet is used. The rotation motor 110 includes a rotor 110a and a stator 110b. The stator 110b also serves as the second arm tip pulley 105. A groove is formed on the upper surface of the stator 110b along the circumference. A ring-shaped rotor 110a is arranged in the groove. The rotor 110a is fixed to a third arm drive shaft 123 provided at the center of the third arm. When the rotor 110a rotates, the third arm 120 rotates minutely around the central axis P3 (the third joint 121). The rotation motor 110 rotates in a direction opposite to the rotation direction of the third arm 120 by the rotation mechanism, and dynamically cancels residual vibration due to rotation of the rotation mechanism.
[0029]
The operation of each arm will be described with reference to FIG.
The first arm 80 rotates around the first joint 81 by driving the first arm drive shaft 23. The second arm 100 rotates around the second joint 101 with respect to the first arm 80 by driving the second arm drive shaft 21. Further, in the third joint 121, the second arm 100 and the third arm 120 rotate by the same angle in opposite directions to each other, so that the angle of the third arm 120 with respect to the first arm 80 does not change. .
[0030]
With such a configuration, when the first arm drive shaft 23 of the motor unit 10 rotates, the first arm 80, the second arm 200, and the third arm 120 form a set and move in the XY plane around the first joint 81 in the Z direction. Rotate around an axis. When the second arm drive shaft 21 of the unit 10 rotates, the second arm 100 rotates about the second joint 101 around the Z axis in the XY plane. At this time, the third arm 120 rotates in a direction opposite to the rotation direction of the second arm 100. Further, the first arm drive shaft 23 and the second arm drive shaft 21 include a moving mechanism in the Z direction (details will be described later). Therefore, the end effector 125 moves in the XYZ directions, and can move the mask or the wafer from a predetermined position to another position.
[0031]
Next, the structure of the motor unit will be described with reference to FIG.
A second arm drive shaft 21 extending in the Z direction and a first arm drive shaft 23 fitted on the outer periphery of the shaft 21 are arranged at the center in the casing 11. Both drive shafts rotate independently of each other about the motor unit center axis P1. The first arm drive shaft 23 has a substantially cylindrical shape, and is disposed coaxially and concentrically on the outer periphery of the second arm drive shaft 21. The second arm drive shaft 21 and the first arm drive shaft 23 are fitted via two upper and lower bearings 25. The second arm drive shaft 21 at the center of the motor unit has a small diameter portion, a medium diameter portion, and a large diameter portion from above, and an upper bearing 25 is disposed at a step between the small diameter portion and the middle diameter portion. A lower bearing 25 is arranged at a step between the diameter part and the large diameter part. Thereby, both shafts 21 and 23 can rotate independently. The shafts 21 and 23 are driven up and down by a lift (Z drive) motor 47 to be described later. As described above and as shown in FIG. 2, a belt drive pulley 27 is fixed to the upper end of the second arm drive shaft 21, and the upper end of the first arm drive shaft 23 is fixed to the first arm 80. Have been.
[0032]
In the casing 11, a concentric cylindrical inner core 29 and an outer core 31 are arranged. Both cores are suspended concentrically with the motor unit central axis P1 so as to partition the inside of the casing. The upper ends of both cores are fixed to the ceiling part 19 of the casing 11. The lower end of the inner core 29 extends over the middle portion 15b of the bottom wall of the casing, and the lower end of the outer core 31 extends over the outermost 15c of the wall.
[0033]
A first arm drive shaft rotation motor 33 is arranged on an inner peripheral portion of the inner core 29. The motor 33 is an electromagnetic rotating motor including a coil (main rotor) 33a and a magnet (main stator) 33b. The coil 33a is fixed along the outer surface of the lower part of the first arm drive shaft 23. The magnet 33b is fixed along the inner surface of the inner core 29 so as to face the coil 33a.
[0034]
An extension member 41 is fixed to the lower end of the second arm drive shaft 21 at the center of the motor unit. The extension member 41 includes an inner cylindrical portion 37 fixed to the lower end of the second arm drive shaft 21, a disk portion 38 connected to the lower end of the cylindrical portion 37, and an outer cylindrical portion connected to the outer periphery of the same portion 38. 39. Both cylindrical portions 37 and 39 are arranged concentrically with respect to the axis P1.
The inner cylindrical portion 37 is located so as to surround the central portion 15a of the casing bottom wall, and a bearing 43 is interposed between the inner cylindrical portion 37 and the central portion 15a. The connection disk 38 is located on the middle part 15b of the casing bottom wall. The outer cylindrical portion 39 extends upward between the inner core 29 and the outer core 31 in parallel with both cores. There is a certain gap between the upper end of the outer cylindrical portion 39 and the upper end of each of the cores 29 and 31 (the ceiling portion 19 of the casing) and between the disc portion 38 and the lower end of the inner core 29. I have.
[0035]
A second arm drive shaft rotation motor 45 is disposed above the inner periphery of the outer cylindrical portion 39 of the extension member 41. This motor is an electromagnetic rotary motor composed of a coil (main rotor) 45a and a magnet (main stator) 45b. The coil 45a is fixed along the inner surface of the upper part of the outer cylindrical portion 39 of the extension member. The magnet 45b is fixed along the outer peripheral surface of the upper part of the inner core 29 so as to face the coil 45a. The second arm drive shaft rotation motor 45 is located at the same height as the first arm drive shaft rotation motor 33. The second arm drive shaft rotating motor 45 rotates the second arm drive shaft 21 together with the extension member 41.
[0036]
A linear motor (elevating mechanism) 47 for moving in the Z direction is provided below the inner periphery of the extension member 41. As the linear motor 47, for example, a voice coil motor can be used. The voice coil motor includes a coil (main mover) 47a and a magnet (main stator) 47b. The coil 47a is fixed along the inner surface below the outer cylindrical portion 39 of the extension member. The magnet 47b is fixed along the outer surface of the lower portion of the inner core 29 so as to face the coil 47a. By the linear motor 47, the second arm drive shaft 21 and the first arm drive shaft 23 are driven up and down in the Z-axis direction together with the extension member 41.
[0037]
With such a configuration, the first arm drive shaft 23 rotates around the Z axis, the second arm drive shaft 21 rotates around the Z axis, and the first arm drive shaft 23 and the second arm drive shaft 21 move in the Z direction. Raise and lower.
[0038]
The motor unit 10 of this example further includes a mechanism for canceling a reaction force and magnetism generated by driving the arm drive shaft and the belt drive shaft.
That is, when each drive shaft rotates, a reaction force is applied to the stator of each motor. In this specification, the reaction force includes both the torque reaction force in the rotational direction and the reaction force in the linear direction. Further, since the motor is of an electromagnetic drive type, AC magnetic field leakage from the coil and DC magnetic field leakage from the magnet also occur from the arm rotation motors 33 and 45. Further, the mass may move due to the above-described arm extending operation, and vibration may occur.
[0039]
The canceling mechanism includes two upper and lower reaction force canceling motors 59 and 63 arranged outside the outer core 31 and two upper and lower counterweight sleeves (CW sleeves) 51 and 53.
[0040]
The upper cancel motor 59 includes a coil (cancel rotator) 59a and a magnet (cancel stator) 59b. The coil 59a is fixed along the inner surface of the upper CW sleeve 51. The magnet 59b is fixed along the outer surface of the upper part of the outer core 31 so as to face the coil 59a. The cancel motor 59 is located at the same height position as the first arm drive shaft rotation motor 33 and the second arm drive shaft rotation motor 45.
[0041]
The lower cancel motor (RC motor) 63 includes a coil (RC mover) 63a and a magnet (RC stator) 63b. The coil 63a is fixed along the inner surface of the lower CW sleeve 53. The magnet 63b is fixed along the outer surface of the lower part of the outer core 31 so as to face the coil 63a. The RC motor 63 is located at the same height position as the Z movement linear motor 47.
[0042]
Each of the CW sleeves 51 and 53 is arranged between the side wall 13 of the casing 11 and the outer core 31 and concentrically with the motor unit central axis P1. The upper surface of the upper CW sleeve 51 is held on the side wall 13 of the casing main body via a bearing 55, and the lower portion of the inner surface is held at the center of the outer surface of the outer core 31 via a bearing 57. As described above, the coil 59a of the upper cancel motor 59 is fixed along the inner surface of the upper CW sleeve 51, and the upper CW sleeve 51 is driven by the motor 59 and rotates about the axis P1.
The lower portion of the lower CW sleeve 53 is held on the outer surface of the outer core 31 via a bearing 61. A certain distance is provided between the lower end of the lower CW sleeve 53 and the casing bottom wall 15c. As described above, the coil 63a of the cancel motor 63 is fixed along the inner surface of the lower CW sleeve 53, and the lower CW sleeve 53 is driven by the motor 63 to move up and down in the Z direction along the axis P1. I do.
[0043]
As described above, the magnet (cancel stator) 59b of the cancel motor 59 is fixed to the outer periphery of the outer core 31. The outer core 31 is fixed to the ceiling member 19 of the casing together with the inner core 29 to which the main stators 33b and 45b for rotating the arm drive shafts 23 and 21 are fixed. Is considered one. That is, the reaction force applied to the stators 33b and 45b when rotating the motors 33 and 45 for rotating both shafts is transmitted to the cancel stator 59b of the cancel motor 59 via the inner core 29 and the outer core 31. Therefore, by rotating the cancel rotor 59a and the upper CW sleeve 51 in the opposite directions of the shafts 21 and 23, a reaction force for canceling the reaction force is applied to the cancel stator 59b. Then, the reaction forces (torques) of the motors 33, 45, and 59 cancel each other in the cores 29 and 31 and do not come out of the motor unit 10. In this way, the motor unit 10 does not shake (apply vibration) the device (exposure device) to which it is attached.
[0044]
Next, a description will be given of the canceling of the reaction force in the extending direction (linear direction) of the arm.
As shown in FIGS. 2 and 6, a mass balancer 70 extending in the opposite direction (radial direction) to the first arm 50 is provided at the tail end (left side in the figure) of the first arm 50.
The mass balancer 70 includes a guide 71 extending in a direction opposite to the first arm 50, and a counterweight (CW) 73 slidable along the guide 71. The weight of the counterweight 73 corresponds to the weight of a portion (the second arm 100, the third arm 120, the end effector 125, the motor 110, and the like) ahead of the second joint 101. An actuator 75 is provided between the guide 71 and the counter weight 73. As the actuator 75, a non-magnetic ultrasonic linear motor or the like can be used. The actuator 75 causes the counter weight 73 to slide on the guide 71 in both directions.
[0045]
The mass balancer 70 cancels the acceleration / deceleration of the mass caused by the extension / retraction of the first to third arms. In other words, acceleration / deceleration in the opposite direction to the acceleration / deceleration applied to the equivalent mass of the arm is given to the counterweight 73 so that the reaction force is balanced within the arm, so that the reaction force does not come out of the motor unit 10.
[0046]
As shown in FIG. 3 and the like, a magnetic shield 140 is provided on the outer surface of the casing 11 so as to cover the same surface at a predetermined interval (for example, several mm). The magnetic shield 140 includes a main body 141 surrounding the main body 17 of the casing 11 and a lid 143 covering the ceiling 19. The magnetic shield 140 is made of a high magnetic permeability material such as permalloy.
The magnetic shield 140 cancels the leakage of the DC magnetic field generated from the magnets 33b, 45b, 47b, 59b, 63b of each motor in the motor unit 10.
[0047]
Next, the reaction force of the motor and the operation of the magnetic cancel mechanism accompanying the operation of the substrate loader 1 will be comprehensively described.
The substrate loader 1 transfers wafers and reticles mainly between the cassette and the stage as described above. At this time, the substrate loader 1 performs a loading operation of placing the substrate on the end effector 125 from the target position, an unloading operation of removing the substrate from the target position on the end effector 125, and a standby operation. The initial position of the substrate loader 1 is such that the arms 80, 100, and 120 are aligned on a straight line.
[0048]
FIG. 7 is a sectional perspective view showing an operation state of the substrate loader of FIG.
FIG. 8 is an enlarged sectional perspective view showing the substrate loader of FIG.
In the following drawings, illustration of a motor portion is omitted. In addition, the rotation direction referred to below indicates a state viewed from above.
In this state, the first arm 80 rotates slightly counterclockwise about the first joint 81, the second arm 100 rotates slightly clockwise about the second joint 101, and the third arm 120 rotates. This is a state where the third joint 121 is rotated counterclockwise slightly. Then, the center of the end effector 125 of the third arm 120 is located at the loading point RP.
[0049]
In the motor unit 10, the first arm drive shaft rotation motor 33 rotates counterclockwise (arrow R1), and the second arm drive shaft rotation motor 45 rotates clockwise (arrow R2).
[0050]
As described above, the two drive shafts 23 and 21 rotate in the opposite directions, and the inner core 29 to which the main stators 33b and 45b of the rotation motors 33 and 45 of each shaft are fixed has the rotation of the two shafts. A rotational reaction force is applied by the difference in torque. In this case, a clockwise reaction torque is applied to the inner core 29. Therefore, the cancel rotor 59a and the CW sleeve 51 are rotated counterclockwise, which is the opposite direction of the reaction torque of both shafts, to apply a reaction force to cancel the reaction force to the cancellation stator 59b. As a result, the reaction forces (torques) of the motors 33, 45, and 59 cancel each other in the cores 29 and 31, and do not come out of the motor unit 10.
[0051]
Further, the actuator 75 of the mass balancer 70 is driven to move the counterweight 73 along the guide 71 in a direction toward the first arm 80 (radial direction, arrow C2). Then, the acceleration / deceleration of the mass caused by the extension / retraction of the first to third arms is canceled. That is, the acceleration / deceleration applied to the equivalent mass of the arm is given to the counter weight 73 so that the reaction force is balanced within the arm so that the reaction force does not come out of the motor unit 10.
[0052]
FIG. 9 is a cross-sectional perspective view showing the elevating operation state of the substrate loader of FIG.
FIG. 10 is an enlarged sectional perspective view showing the substrate loader of FIG.
This state shows a state in which the entire arm has risen in the Z direction from the state of FIG. That is, the linear motor 47 is driven upward (arrow M1) to drive the first arm drive shaft 23 and the second arm drive shaft 21 together in the Z direction.
[0053]
At this time, the RC motor 63 is driven downward (arrow C3), and the lower CW sleeve 53 is moving downward. This cancels the acceleration / deceleration of the mass caused by the upward movement of the first to third arms. That is, acceleration / deceleration applied to the equivalent mass of the arm is applied to the lower CW sleeve 53 so that the reaction force is balanced within the motor unit 10 so that the reaction force is not generated outside the motor unit 10.
[0054]
FIG. 11 is a sectional perspective view showing a state where the substrate loader of FIG. 1 is on standby.
FIG. 12 is an enlarged sectional perspective view showing the substrate loader of FIG.
In this state, the second arm 100 is in the most retracted state, that is, the first arm 80 rotates about 90 ° counterclockwise around the first joint 81 from the initial state, and the second arm 100 The arm is rotated about 90 ° clockwise from the initial state around the joint 101 (rotated 180 ° with respect to the first arm 80), and both arms 80 and 100 are folded so as to overlap. The third arm 120 is angularly located at the initial position.
[0055]
In the motor unit 10, the first arm drive shaft rotation motor 33 rotates counterclockwise (arrow R1 '). Then, the second arm drive shaft rotating motor 45 is rotating clockwise (arrow R2 ').
[0056]
Then, in order to cancel the rotational reaction force applied to the stator fixed to each shaft, the cancel motor is driven to rotate the upper CW sleeve 51 largely clockwise (arrow C3). Here, the rotation direction of each arm is the same as that of FIG. 7, but the rotation direction of the CW sleeve 51 is different in order to cancel the torque generated by the arm turning around the axis.
Further, the actuator 75 of the mass balancer 70 is driven to move the weight 71 in a direction approaching the first arm 80 (arrow C5).
[0057]
FIG. 13 is a diagram schematically illustrating a state of a magnetic field accompanying operation of the reaction force canceling mechanism. In the figure, a broken line indicates a magnetic field generated from the cancel rotor 59a of the cancel motor 59, and a solid line indicates a magnetic field obtained by combining the magnetic fields generated by the main rotors 33a and 45a of the motors 33 and 45. The upper arrow indicates the rotational direction of the cancel motor 59, and the lower arrow indicates the rotational direction of the combined energy of the motors 33 and 45.
As can be seen from the figure, the rotation direction of the cancel motor 59 and the rotation direction of the combined energy of the rotation energies of the motors 33 and 45 for rotating the respective arms are opposite to each other as described above. Are controlled so that the phase of the magnetic field is shifted by 180 °. For this reason, the magnetic field of each motor is canceled as a whole, and the leaked AC magnetic field is cancelled.
[0058]
Also, during the operation described above, DC magnetic field leakage from the magnet of each motor is shielded by the magnetic shield 140.
[0059]
This substrate loader 1 is installed in a wafer chamber 206 (see FIG. 15) of the exposure apparatus. Then, the wafer is transferred using the loader 1. During the transfer of the wafer, the exposure operation is performed in parallel. At this time, the loader does not affect the trajectory of the electron beam because the leakage of the magnetic field and the occurrence of vibration are reduced as described above.
[0060]
【The invention's effect】
As is apparent from the above description, according to the present invention, it is possible to provide a substrate loader capable of handling an end effector at high speed. By using such a substrate loader, an exposure apparatus with improved throughput can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional perspective view showing an overall structure of a substrate loader according to an embodiment of the present invention.
FIG. 2 is a sectional perspective view showing an enlarged structure of a motor unit of the substrate loader of FIG. 1;
FIG. 3 is a front sectional view of the motor unit of FIG.
FIG. 4 is an enlarged sectional perspective view showing a structure of a first arm of the substrate loader of FIG. 1;
FIG. 5 is an enlarged sectional perspective view showing a structure of a second arm and a third arm of the substrate loader of FIG. 1;
FIG. 6 is a cross-sectional view schematically illustrating a structure of a mass balancer of the substrate loader of FIG. 2;
FIG. 7 is a sectional perspective view showing an operation state of the substrate loader of FIG. 1;
FIG. 8 is an enlarged sectional perspective view showing the substrate loader of FIG. 7;
FIG. 9 is a cross-sectional perspective view showing an elevating operation state of the substrate loader of FIG. 1;
10 is an enlarged sectional perspective view showing the substrate loader of FIG. 9;
11 is a cross-sectional perspective view showing a state where the substrate loader of FIG. 1 is on standby.
FIG. 12 is an enlarged sectional perspective view showing the substrate loader of FIG. 11;
FIG. 13 is a diagram schematically showing a state of a magnetic field associated with an operation of a reaction force canceling mechanism.
FIG. 14 is a diagram showing an outline of an imaging relationship and a control system in the entire optical system of the projection exposure type electron beam exposure apparatus.
FIG. 15 is a plan view schematically illustrating a wafer transfer mechanism in a general wafer chamber.
DESCRIPTION OF SYMBOLS 1 Substrate loader 10 Motor unit 11 Casing 13 Side wall 15 Bottom wall 17 Main part 19 Ceiling part 21 Second arm drive shaft (belt pulley drive shaft)
23 First arm drive shaft 25 Bearing 27 Belt drive pulley 29 Inner core 31 Outer core 33 First arm drive shaft rotating motor 35 Bearing 37 Inner cylindrical portion 38 Connecting disk portion 39 Outer cylindrical portion 41 Extension member 43 Bearing 45 Second arm Drive shaft rotation motor 47 Lifting (Z drive) motor 51 Upper CW sleeve 53 Lower CW sleeve 55 Bearing 57 Bearing 59 Cancel motor 61 Bearing 63 Cancel motor 70 Mass balancer 71 Guide 73 Counter weight (CW)
75 actuator 80 first arm 81 first joint 83 first arm tip pulley 85 first arm tip shaft 87 bearing 88 second arm drive shaft 89 belt 100 second arm 101 second joint 103 second arm proximal pulley 105 second Arm tip pulley 107 Second arm tip shaft 109 Belt 110 Motor 111 Bearing 120 Third arm 121 Third joint 125 End effector 140 Magnetic shield 141 Main body 143 Cover

Claims (3)

A board mounting arm,
An arm extension mechanism,
An elevating mechanism for the arm,
An electromagnetic rotary motor that is an integrated drive source of the two mechanisms,
A substrate loader comprising:
A substrate loader further comprising a fine rotation mechanism for rotating the substrate mounting arm. 2. The substrate loader according to claim 1, wherein the fine rotation mechanism includes an actuator such as an ultrasonic motor or an air motor that does not generate a disturbance magnetic field. Sensitive substrate transfer system,
An optical system for selectively irradiating the sensitive substrate with energy rays to form a device pattern on the sensitive substrate;
An exposure apparatus comprising:
An exposure apparatus, wherein the sensitive substrate transport system includes the substrate loader according to claim 1 or 2.

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