Substrate transfer device and power supply method for substrate transfer device
12550668 ยท 2026-02-10
Assignee
Inventors
Cpc classification
International classification
Abstract
Provided is a substrate transfer device comprising: a tile part forming a moving surface of an area where a substrate is transferred and provided with a plurality of first coils that generate magnetic field on the moving surface by a power supplied from a power supply part; and a substrate transfer module including a plurality of magnets that exert a repulsive force against the magnetic field and a substrate holder configured to hold a substrate to be transferred, the substrate transfer module configured to move above the moving surface by magnetic levitation using the repulsive force, wherein the substrate transfer module includes a second coil for wirelessly supplying a power to a power consuming device provided in the substrate transfer module during movement above the moving surface using an electromotive force that is exerted against the magnetic field generated by the first coils.
Claims
1. A substrate transfer device comprising: a tile part forming a moving surface of an area where a substrate is transferred and provided with a plurality of first coils that generate magnetic field on the moving surface by a power supplied from a power supply part; and a substrate transfer module including a plurality of magnets that exert a repulsive force against the magnetic field and a substrate holder configured to hold a substrate to be transferred, the substrate transfer module configured to move above the moving surface by magnetic levitation using the repulsive force, wherein the substrate transfer module includes a second coil for wirelessly supplying a power to a power consuming device provided in the substrate transfer module during movement above the moving surface using an electromotive force that is exerted against the magnetic field generated by the first coils.
2. The device of claim 1, wherein the magnet and the second coil are arranged without overlapping each other when viewed from the moving surface, and the apparatus further comprising: a power supply controller configured to switch, for each of the plurality of first coils disposed at the tile part, a supplying state of the power supplied from the power supply part between a driving mode for moving the substrate transfer module, a wireless power supply mode for supplying a power to the second coil, and a standby mode in which no power is supplied, depending on the position of the second coil and the positions of the magnets of the substrate transfer module moving above the moving surface.
3. The device of claim 2, wherein the power supply part is configured to supply an AC power to the plurality of first coils, and in the wireless power supply mode, the power supply controller controls the power supply part to decrease a frequency of the AC power as a moving speed of the substrate transfer module increases with respect to a coil, which is arranged in a direction that generates a magnetic flux penetrating through an opening surface of the second coil, among the plurality of first coils in order to suppress variation in the electromotive force.
4. The device of claim 2, wherein the tile is provided with the plurality of first coils arranged to extend in different directions along the moving surface when viewed from a vertical axis intersecting with the moving surface, the power supply part is configured to supply the AC power to the plurality of first coils, and in the wireless power supply mode, the power supply controller controls the power supply part to change a maximum current value of the AC power supplied to a coil, which is arranged to extend in one direction, among the plurality of first coils or the plurality of first coils arranged to extend in different directions in response to rotational movement of the substrate transfer module around the vertical axis in order to suppress variation in the electromotive force.
5. The device according to claim 2, wherein the tile is provided with the plurality of first coils arranged to extend in different directions along the moving surface when viewed from the vertical axis intersecting with the moving surface, the power supply part is configured to supply the AC power to the plurality of first coils, and in the wireless power supply mode, the power supply controller controls to switch the supplying state of the power supplied to a coil, which is arranged to extend in a direction that becomes close to the magnet of the substrate transfer module, among the plurality of first coils to a mode other than the wireless power supply mode, and switch the supplying state of the power supplied to another coil, which is arranged to extend in a direction that becomes distant from the magnet, among the plurality of first coils to the wireless power supply mode, in response to the rotational movement of the substrate transfer module around the vertical axis in order to avoid influence of magnetic field generated at the second coil on a moving operation of the substrate transfer module.
6. The device according to claim 1, wherein the substrate transfer module includes: a main body provided with the magnet; and a fork disposed to extend in a direction along the moving surface from the main body and having the substrate holder at a tip end thereof, wherein the second coil is disposed at the fork.
7. The device of claim 1, wherein the substrate transfer module includes a battery that stores the power supplied through the second coil and supplies the power to the power consuming device.
8. The device of claim 7, wherein the substrate transfer module includes: an AC/DC conversion circuit disposed between the second coil and the battery and configured to convert the AC power supplied through the second coil into a DC power; and a voltage regulator configured to adjust a voltage of the DC power converted by the AC/DC conversion circuit.
9. The device of claim 1, wherein the power consuming device is a sensor disposed at the substrate transfer module.
10. A power supply method for a device for transferring a substrate, comprising: moving a substrate transfer module above a moving surface of an area where the substrate is transferred by magnetic levitation using a repulsive force, by using a tile part forming the moving surface and provided with a plurality of first coils that generate magnetic field at the moving surface by a power supplied from a power supply part, and by using the substrate transfer module including a plurality of magnets that exert the repulsive force against the magnetic field, and a substrate holder configured to hold the substrate to be transferred; and wirelessly supplying a power to a power consuming device provided in the substrate transfer module using a second coil for power supply disposed at the substrate transfer module during said moving the substrate transfer module above the moving surface using an electromotive force acting between the magnetic field generated by the first coils and the second coil.
11. The method of claim 10, wherein in the substrate transfer module, the magnets and the second coil are arranged without overlapping each other when viewed from the moving surface, and the method further comprising: switching, for each of the first coils disposed at the tile part, a supplying state of the power supplied from the power supply part between a driving mode for moving the substrate transfer module, a wireless power supply mode for supplying a power to the second coil, and a standby mode in which no power is supplied, depending on the position of the second coil and the positions of the magnets of the transfer module during said moving the substrate transfer module above the moving surface.
12. The method of claim 11, wherein the power supply part is configured to supply an AC power to the plurality of first coils, and in said switching the power supply state from the power supply part, the frequency of the AC power is controlled to decrease as the moving speed of the substrate transfer module increases with respect to a coil, which is arranged in a direction that generates a magnetic flux penetrating through the opening surface of the second coil, among the plurality of first coils in order to suppress variation in the electromotive force in the wireless power supply mode.
13. The method of claim 11, wherein the tile is provided with a plurality of first coils arranged to extend in different directions along the moving surface when viewed from a vertical axis intersecting with the moving surface, the power supply part is configured to supply an AC power to the plurality of first coils, and in said switching the power supply state from the power supply part, in the wireless power supply mode, a maximum current value of the AC power is controlled to change in order to suppress variation in the electromotive force for a coil, which is arranged to extend in one direction, among the plurality of first coils or the plurality of first coils arranged to extend in different directions in response to the rotational movement of the substrate transfer module around the vertical axis.
14. The method of claim 11, wherein the tile is provided with a plurality of first coils arranged to extend in different directions along the moving surface when viewed from a vertical axis intersecting with the moving surface, and in said switching the power supply state from the power supply part, the supplying state of the power supplied to a coil, which is arranged to extend in a direction that becomes close to the magnet of the substrate transfer module, among the plurality of first coils is switched to a mode other than the wireless power supply mode and the supplying state of the power supplied to another coil, which is arranged to extend in a direction that becomes distant from the magnet, among the plurality of first coils is switched to the wireless power supply mode in response to the rotational movement of the substrate transfer module around the vertical axis in order to avoid influence of magnetic field generated at the second coil controlled to the wireless power supply mode on a moving operation of the substrate transfer module.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(23) <Substrate Processing System>
(24) Hereinafter, an example of a configuration of a substrate processing system 1 that is an apparatus for transferring a substrate according to an embodiment of the present disclosure will be described with reference to
(25)
(26) Load ports 121 on which carriers C accommodating wafers W to be processed are placed are disposed at the front side of the atmospheric transfer chamber 12. The carrier C may be, e.g., a front opening unified pod (FOUP). The atmospheric transfer chamber 12 is maintained at an atmospheric pressure (normal pressure), and a transfer mechanism 122 is disposed therein to transfer the wafer W between the carrier C and the load-lock chambers 13.
(27) An inner atmosphere of the load-lock chamber 13 can be switched between an atmospheric pressure atmosphere and a vacuum atmosphere, and a transfer stage 130 on which the wafer W is placed and lift pins 131 are provided in the load-lock chamber 13.
(28) As shown in
(29) For example, four substrate processing chambers 11 are connected to each of the left side and the right side of the substrate transfer chamber 14, and openings 110 for transferring wafers W to the substrate processing chambers 11 are formed between the substrate transfer chamber 14 and the substrate processing chambers 11. In
(30) Further, substrate transfer modules (hereinafter, referred to as transfer modules) 2 for transferring the wafers W between the load-lock chambers 13 and the substrate processing chambers 11 are disposed in the substrate transfer chamber 14.
(31) For example, the substrate transfer chamber 14 has a short side length that allows two transfer modules 2 arranged in the left-right direction and holding the wafers W to pass each other without interference. In the substrate transfer chamber 14, the wafers W are transferred using the plurality of transfer modules 2. In this example, a plurality of first coils 3 are disposed at the tile part 16 forming the moving surface 15, and the transfer module 2 is configured to move by utilizing magnetic levitation using the repulsive force against the first coils 3. The specific configurations of the first coils 3 and the transfer module 2 will be described later.
(32) Each substrate processing chamber 11 is depressurized to a vacuum atmosphere by a vacuum exhaust mechanism (not shown). A placing table 111 and lift pins 112 are disposed in each substrate processing chamber 11, and predetermined processing is performed on the wafer W placed on the placing table 111. The lift pins 112 and 131 are configured to lift up and hold the wafer W, and transfer the wafer W. The processing performed on the wafer W may be etching, film formation, cleaning, ashing, or the like.
(33) <Controller>
(34) The substrate processing system 1 includes a controller 5. The controller 5 is a computer having a central processing unit (CPU) and a storage part, and controls individual components of the substrate processing system 1. The storage part records a program having steps (commands) for controlling the operation of the substrate processing chamber 11. The program is stored in a storage medium such as a hard disk, a compact disk, a magneto-optical disk, a memory card, or a non-volatile memory, and is installed in the computer therefrom. The storage part also stores a program for moving the transfer module 2 or performing power supply. The controller 5 constitutes a power supply controller 501 to be described later, and is configured to control the function related to the movement of the transfer module 2 or the wireless power supply.
(35) An example of transfer of the wafer W in the substrate processing system 1 will be briefly described. The wafer W in the carrier C placed on the load port 121 is transferred to the load-lock chamber 13 maintained in an atmospheric pressure atmosphere by the transfer mechanism 122. Next, the inner atmosphere of the load-lock chamber 13 is switched from an atmospheric pressure atmosphere to a vacuum atmosphere and, then, the wafer W in the load-lock chamber 13 is transferred to the substrate processing chamber 11 for processing the wafer W by the transfer module 2.
(36) In the substrate processing chamber 11, the wafer W placed on the placement table 111 is heated to a preset temperature, if necessary, and a processing gas is supplied into the substrate processing chamber 11 when a processing gas supply part is provided. Accordingly, desired processing is performed on the wafer W.
(37) After the wafer W is processed, the wafer W is transferred in a reverse order of the loading process, and is returned from the substrate processing chamber 11 to the load-lock chamber 13. Further, after the inner atmosphere of the load-lock chamber 13 is switched to an atmospheric pressure atmosphere, the wafer W is returned to a predetermined carrier C by the transfer mechanism 122.
(38) <Substrate Transfer Module>
(39) In the substrate processing system 1 having the above-described schematic configuration, the transfer module 2 is configured to be movable in the substrate transfer chamber 14 by magnetic levitation. The transfer module 2 has a function of not only transferring the wafer W but also wirelessly supplying a power to a power consuming device disposed in the transfer module 2. Hereinafter, the configuration of devices related to the transfer of the wafer W using the transfer module 2 and the wireless power supply will be described.
(40)
(41) As shown in
(42) The fork 22 has a length that allows the wafer W to be transferred to the placing table 111 by inserting it into the substrate processing chamber 11 through the opening 110 where the gate valve G3 is opened in a state where the main body 21 is positioned in the substrate transfer chamber 14. As shown in
(43) The main body 21 is provided with magnets 4 (see
(44) Further, a second coil 6 for wirelessly supplying a power to the sensor 51 is disposed at a position close to the substrate holder 23 on the bottom surface side of the fork 22, for example. In this manner, the second coil 6 and the magnets 4 are arranged at positions where they do not overlap each other when viewed from the moving surface 15. Further, as shown in
(45) <Tile Part>
(46) Next, the tile part 16 constituting the moving surface 15 of the substrate transfer chamber 14 will be described with reference to
(47) As shown in
(48) The first coil 3 will be described with reference to
(49) As described with reference to
(50) The area in which the first coils 3 are installed is the entire moving area of the transfer module 2, which is from the transfer position (facing the load-lock chambers 13) of the wafer W with respect to the atmospheric transfer chamber 12 to the front side of the substrate processing chamber 11, and the surface of the moving area corresponds to the moving surface 15. If the moving area is set such that the transfer module 2 moves into the load-lock chambers 13 or the substrate processing chamber 11, the first coils 3 are also disposed on the bottom surfaces of the load-lock chambers 13 or the substrate processing chamber 11.
(51) The plurality of A coils 31 are arranged at intervals in the X direction to extend along the Y direction. The plurality of B coils 32 are arranged at intervals in the Y direction to extend along the X direction. Each of the A coils 31 and the B coils 32 is formed of coil wires a and b.
(52) As schematically shown in
(53) As shown in
(54) Similarly, each of the vertically stacked coil wires b is electrically connected, at one or the other end thereof in the X direction, to one end or the other end of the coil wire b disposed on the upper or lower layer side. When viewed in the X-Z vertical cross section, the stacked coil wires b are connected in a spiral shape, for example, and both ends thereof are connected to the power supply part 34, thereby forming the B coil 32.
(55) The power supply part 34 is configured to supply a power to the selected A coil 31 and B coil 32 based on a command from the controller 5 (the power supply controller 501), and generate magnetic field on the upper surface of the tile part 16 in the area where the A coil 31 and B coil 32 to which the power has been supplied are arranged. For convenience of illustration, only the power supply part 34 corresponding to one A coil 31 is shown in
(56) The A coils 31 and B coils 32 are arranged in the same manner in each of the tile parts T. By arranging each tile unit T on the bottom surface of the substrate transfer chamber 14, the A coil 31 and the B coil 32 disposed at the adjacent tile unit T are connected to each other, and the A coil 31 and the B coil 32 are arranged on the entire moving surface 15 that is the bottom surface.
(57) As shown in
(58) Next, the main body 21 of the transfer module 2 will be described. As shown in
(59) Each of the magnets 4 includes multiple, e.g., nine permanent magnets 45 arranged in a Halbach array.
(60) In the transfer module 2 configured as described above, the A coil 31 and the B coil 32 located below the area where the magnets 4 (41, 42, 43 and 44) are arranged are selected to supply a power flowing in a predetermined direction. As a result, the repulsive force is generated between the magnetic field generated by the first coils 3 and the magnetic field of the magnets 4, and is used to move the main body 21. For example, in
(61) In this manner, in the A coils 31 and the B coils 32, the position where the magnetic field is generated, the magnitude of the magnetic force, and the direction of the magnetic field are adjusted. Further, by controlling the magnetic field, the levitation amount (levitation distance) of the main body 21 from the moving surface 15, the direction of the main body 21, and the moving direction of the main body 21 are adjusted. As a result, the main body 21 can have a desired position above the moving surface 15, and can move in a desired direction.
(62) Further, the tile part 16 is provided with a plurality of Hall elements (position detection sensors) (not shown). The Hall element is an example of a magnetic sensor, and detects the position and the direction of the main body 21. The moving speed of the main body 21 can also be detected by the Hall elements.
(63) In this manner, the transfer module 2 is configured to be freely movable in the X, Y, Z, and 0 directions in the substrate transfer chamber 14, and can move with a high degree of freedom in the substrate transfer chamber 14. Therefore, there is a demand for a mechanism capable of supplying a power to the sensor 51 attached to the transfer module 2 without affecting the transfer operation of the transfer module 2.
(64) Here, the power can be supplied by wire or using a pre-charged large-capacity battery. In that case, however, the weight of the battery or the length of the cable may cause deterioration in the operating performance of the transfer module 2.
(65) Further, the wireless power supply can be performed by stopping the transfer module at a preset power supply point and supplying a power, or by installing a power transmission part on the bottom surface of the substrate transfer chamber along the transfer path of the wafer W, or by transmitting a power by radiating radio waves of a microwave band from the power transmission part. However, in the case of stopping the transfer module, a throughput may deteriorate, and in the case of installing the power transmission part along the transfer path, the transfer path may be limited. Further, in a configuration in which a new power transmission part is installed on the bottom surface, the existing device needs to be expanded considerably. Further, in the case of using radio waves of the microwave band, when the radio waves are emitted in the substrate processing chamber, reflection occurs and a power cannot be supplied due to the effects of standing waves, so that stable power supply cannot be achieved.
(66) Hence, the present disclosure focuses on the case of using the first coils 3 installed in the substrate transfer chamber 14 for wireless power supply on the transfer module 2 side.
(67) (Second Coil of Transfer Module)
(68) As described above, the transfer module 2 includes the second coil 6 for wireless power supply. The second coil 6 is formed by winding a coil wire 62 around a base 61 made of a magnetic material such as ferrite or the like. For example, in the example shown in
(69)
(70) The power supply mechanism 71 on the tile part 16 side includes the power supply part 34 that is a DC power supply part, a DC/AC conversion circuit 711, the power supply controller 501, the switch element 712, and the first coils 3 (the A coil 31 and the B coil 32).
(71) The power supply controller 501 is configured to switch the power supply state from the power supply part 34, for each of the first coils 3 (31 and 32) disposed at the tile part 16, depending on the positions of the magnets 4 of the transfer module 2 moving above the moving surface 15 and the position of the second coil 6. A driving mode for moving the transfer module 2, a wireless power supply mode for supplying a power to the second coil 6, and a standby mode in which no power is supplied are set as the power supply state for the first coils 3.
(72) In the driving mode, the DC power supplied from the power supply part 34 is supplied to the selected A coil 31 and B coil 32 via the switch element 712. In the wireless power supply mode, the DC power supplied from the power supply part 34 is converted to an AC power by the DC/AC conversion circuit 711, and is supplied to the selected A coil 31 or B coil 32 via the power supply controller 501 and the switch element 712.
(73) No power is supplied from the power supply part 34 to the A coil 31 and the B coil 32 in the standby mode.
(74) On the other hand, the power receiving mechanism 72 on the transfer module 2 side includes the second coil 6, an AC/DC conversion circuit 721, a voltage regulator 722, and the battery 52. The AC/DC conversion circuit 721 converts an AC power to a DC power, and the voltage regulator 722 adjusts the voltage of the DC power converted by the AC/DC conversion circuit 721. Accordingly, an AC electromotive force generated between the first coil 3 and the second coil 6 is converted to a DC power by the AC/DC conversion circuit 721, and the voltage is adjusted by the voltage regulator 722, and then is stored in the battery 52, as will be described later. Further, the power is supplied from the battery 52 to the sensors 51 (the position sensor 511 and the inclination sensor 512) so that the position of the substrate holder 23, the inclination of the main body 21, and the like are detected.
(75) Next, the control of the power supply state of the first coils 3 will be described with reference to
(76)
(77) As described above, in the main body 21, a position P.sub.0 shown in
(78) In
(79) A position P of the second coil 6 is calculated based on, e.g., coordinate information of the position P.sub.0 of the main body 21. The position P of the second coil 6 shown in
(80) As described above, an AC power is supplied to the first coils 3 set to the wireless power supply mode, and magnetic field is generated on the moving surface 15 by the first coils 3. Then, the magnetic field generated on the moving surface 15 changes due to the AC power supplied to the first coils 3, and an AC electromotive force acts between the first coils 3 and the second coil 6. As a result, an induced current is generated in the second coil 6, and the induced current is supplied to the AC/DC conversion circuit 721. The first coils 3 to be set to the wireless power supply mode may be one or more first coils 3 (the coil wires a and b) as long as an electromotive force can be generated between themselves and the second coil 6 by supplying a power to the first coils 3 in the corresponding area. Further, the first coils 3 in an area larger than the projection area of the second coil 6 may be set to the wireless power supply mode as long as the action of the first coils 3 set to the driving mode is not disturbed.
(81) As the transfer module 2 moves, the power supply state of the first coils 3 disposed at the tile part 16 is controlled depending on the positions of the magnets 4 and the position of the second coil 6 and, thus, it is possible to wirelessly supply a power to the sensor 51 of the moving transfer module 2. On the other hand, the transfer operation of the wafer W by the transfer module 2 includes translational movement or rotational movement as shown in
(82) First, as shown in
(83) The magnitude of the electromotive force obtained between the first coils 3 and the second coil 6 of the tile part 16 is affected by the magnetic flux of the second coil 6. Since, however, the magnetic flux changes depending on the moving speed or the rotation angle of the transfer module 2, the electromotive force may vary depending on the transfer operation of the transfer module 2. On the other hand, in the present embodiment, a voltage regulator 722 is provided to adjust a voltage at the time of storing the electromotive force in the battery 52. An upper limit value of the inputted voltage of the DC power is set in the voltage regulator 722, so that it is preferable to suppress the variation in the electromotive force. Hence, in the present disclosure, the power supply controller 501 performs control to suppress the variation in the electromotive force during both translational movement and rotational movement.
(84) <Constant Electromotive Force During Translational Movement>
(85)
(86)
(87) In the second coil 6, an electromotive force V is generated due to the change in the magnetic flux B penetrating through the opening surface 63. In the wireless power supply mode, the power supply part 34 supplies an AC power (e.g., I.sub.X=A.sub.X sin t in the case of the A coil disposed along the X direction) to the first coils 3 of the tile part 16, and an AC power based on electromagnetic induction is also obtained on the second coil 6 side by the magnetic field that changes over time due to the above AC power.
(88) On the other hand, while the transfer module 2 is moving, the second coil 6 moves relative to the first coils 3 of the tile part 16. Due to this movement, the magnetic flux B changes, and the electromotive force V in the second coil 6 changes.
(89) As described above, it is preferable to suppress the change in the electromotive force V by the movement of the transfer module 2. Therefore, the power supply controller 501 controls the AC power supplied from the power supply part 34 to the first coils 3 depending on the moving speed V.sub.M at the time of performing translational movement of the transfer module 2. Specifically, the power control reduces the frequency of the AC power as the moving speed V.sub.M of the transfer module 2 increases with respect to the first coil 3 (the A coil 31 in
(90) Hereinafter, the contents of the power control will be described.
(91) On the assumption that the transfer module 2 moves linearly in the X direction at the moving speed V.sub.M as shown in
(92)
(93) Here, A is a constant, is a wavelength, is an angular velocity (=2fsw), and fsw is a frequency. V.sub.M and
are originally functions that depend on time, but are defined as constants here for simplicity.
(94) When the magnetic flux penetrating through the opening 63 of the second coil 6 per unit area is defined as , the electromotive force V is expressed by the following Eq. (2) because is B.
(95)
(96) Here, N is the number of turns of the second coil.
(97) When the relationship in the following Eq. (3) is obtained from the above Eq. (2), the electromotive force V becomes constant.
(98)
(99) . As can be seen from
of the AC power supplied from the power supply part 34 linearly decreases. Accordingly, it is possible to make the average electromotive force (the voltage after conversion to a DC power by the AC/DC conversion circuit 721) in the second coil 6 constant (suppress variation in the electromotive force). Since the angular velocity
is 2fsw, the power supply controller 501 decreases the frequency fsw of the AC power supplied to the A coil a.sub.n directly below the second coil 6 as the moving speed V.sub.M of the transfer module 2 increases, thereby suppressing variation in the electromotive force V.
(100) Here, the case where the transfer module 2 that is disposed such that the fork 22 is parallel to the X direction moves in translation in the X direction has been described as an example. However, the same applies when the transfer module 2 that is disposed such that the fork 22 is parallel to the Y direction moves in translation in the Y direction. In this case, the B coil 32 is disposed in the direction that generates the magnetic flux B penetrating through the opening surface 63 of the second coil 6. The power supply controller 501 is configured to decrease the frequency of the AC power as the moving speed V.sub.M of the transfer module 2 increases in the case of supplying an AC power to the B coil 32.
(101) Further, the transfer module 2 may move in translation in a diagonal direction or may rotate around the center point without changing the direction of the main body 21. In such movement, the frequency change control is performed for both the A coil 31 and the B coil 32 depending on the magnitude of the X-direction and Y-direction components of the moving speed V.sub.M.
(102) Further, the suppression of variation in the electromotive force indicates the suppression of variation in the electromotive force within a range that does not exceed the upper limit of the voltage of the voltage regulator 722, and the variation range of the electromotive force is set by the upper limit of the voltage. For example, it includes the case where the variation is within 20% of the average value of the electromotive force.
(103) <Constant Electromotive Force in Rotational Movement>
(104) Next, the power control by the power supply controller 501 at the time of rotating the transfer module 2 around a rotation axis perpendicular to the moving surface 15 (bottom surface) in the wireless power supply mode will be described with reference to
(105) The power supply controller 501 is configured to select the coil for wireless power supply, which is capable of generating the magnetic flux B penetrating through the opening surface 63 of the second coil 6, between the A coil 31 and the B coil 32 by the rotational movement of the transfer module 2.
(106)
(107) In
(108) As described with reference to t) and I.sub.Y(=A.sub.Y sin
t) of a common frequency are supplied to the A coils 31 and the B coils 32, respectively.
(109) In the transfer module 2 shown in
(110)
(111) Therefore, if the unit vector normal to the opening surface 63 of the second coil 6 is defined as n=(cos , sin , 0), a magnetic flux penetrating through the second coil 6 is expressed by the following Eq. (5).
(112)
(113) Therefore, the electromotive force V in the second coil 6 is expressed by the following Eq. (6).
(114)
(115) When the following relationship (7) is obtained from the above Eq. (6), the electromotive force becomes constant.
(116)
(117) Here, the relationship of cos.sup.2 +sin .sup.2 =1 is obtained.
(118) Therefore, the power control is performed such that the maximum current values of the current values I.sub.X(=A.sub.X sin t) and I.sub.Y(=A.sub.Y sin
t) of the powers supplied to the A coils 31 and the B coils 32 become A.sub.X=cos and A.sub.Y=sin , respectively, depending on the rotation angle of the transfer module 2, for example.
(119) On the other hand, during the rotational movement of the transfer module 2, the distance between the A coil 31 or the B coil 32 to which the power is being supplied in the wireless power supply mode and the magnets 4 disposed in the main body 21 may become short. In this case, it is necessary to suppress the influence of the magnetic field generated around the A coil 31/B coil 32 to which the power is being supplied in the wireless power supply mode on the operation control of the transfer module 2.
(120) Therefore, during the rotational movement, the coil used for wireless power supply may be switched from the B coil 32/A coil 31 that become close to the magnets 4 in the main body 21 to the B coil 32/A coil 31 that become distant from the magnets 4 depending on the rotation angle of the transfer module 2.
(121) For example,
(122) In this case, Eqs. (4) to (7) are calculated to perform the power supply control using any one of the A coil 31 and the B coil 32, and the values of the maximum current values A.sub.X and A.sub.Y are obtained. The signs of the maximum current values A.sub.X and A.sub.Y in
(123)
(124) As shown in
(125) Based on the results of calculating the maximum current values A.sub.X and A.sub.Y, the control in which the AC power supplied to the A coil a.sub.n and the B coil b.sub.n is controlled to become close to the values A.sub.X and A.sub.Y as the rotation angle becomes close to 45n.Math.90 (n=0, 1, 2, 3) is performed. Accordingly, the AC powers of the maximum current values A.sub.X and A.sub.Y are supplied to the A coil a.sub.n and the B coil b.sub.n at the rotation angle =45+n.Math.90 (n-integer including 0, 1, 2, 3) where the influence of the magnetic fields is minimum, thereby suppressing a decrease in the electromotive force at the corresponding positions and suppressing variation in the total electromotive force. The control example of
(126) Next, the operation of the wireless power supply will be described with reference to the flowcharts shown in
(127) First, the position P.sub.0 of the main body 21 of the transfer module 2 is obtained (step S11). The position P.sub.0 of the main body 21 is detected by the Hall element disposed at the tile part 16 as described above. Then, in step S12, it is determined whether or not the detected position P.sub.0 is around the A coil a.sub.n and the B coil b.sub.n, that is, whether the A coil a.sub.n and the B coil b.sub.n are directly below the main body 21. In the case of Yes. the processing proceeds to step S13 to switch the power supply states of the A coil a.sub.n and the B coil b.sub.n to the driving mode, and the driving control of the transfer module 2 is executed (step S14).
(128) On the other hand, in the case of No, the processing proceeds to step S15 to determine whether or not the position P of the second coil 6 is around the A coil a.sub.n and the B coil b.sub.n, that is, whether the A coil a.sub.n and the B coil b.sub.n are directly below the second coil 6. The position P of the second coil 6 is calculated based on the position P.sub.0 of the main body 21, as described above. In the case of Yes, the processing proceeds to step S16 to switch the power supply states of the A coil a.sub.n and the B coil b.sub.n to the wireless power supply mode, and the power supply control is performed (step S20). In the case of No, the processing proceeds to step S17 to switch the power supply states of the A coil a.sub.n and the B coil b.sub.n to the standby mode (step S17).
(129) For the power supply control, in step S21, it is determined whether or not the angle is less than 45+n.Math.90 (n=0, 1, 2, 3). In the case of Yes, the processing proceeds to step S22 to activate the A coil a.sub.n. In the case of No, the processing proceeds to step S23 to active the B coil b.sub.n. The activation means that the A coil a.sub.n (B coil b.sub.n) is selected as the coil to which the AC power is supplied, and the AC power is supplied to the selected A coil a.sub.n (B coil b.sub.n).
(130) Then, in step S24, the frequency of the AC power to be supplied to the activated coil is set based on the moving speed V.sub.M of the transfer module 2. In step S25, the magnitude of the AC power to be supplied to the activated coil is set based on the angle of the transfer module 2. Accordingly, the AC power with the controlled frequency and the controlled magnitude is supplied to the activated A coil a.sub.n (B coil b.sub.n).
(131) In this manner, the power supply state of the first coil 3 corresponding to the position P.sub.0 of the main body 21 of the transfer module 2 is switched to the driving mode, and the power supply state of the first coil 3 corresponding to the position P of the second coil 6 is switched to the wireless power supply mode, and they are driven in the driving mode and the wireless power supply mode, respectively.
(132) In accordance with the present embodiment, by using the electromotive force acting between the second coil 6 disposed at the transfer module 2 and the magnetic field generated by the first coils 3 of the tile part 16, the power can be wirelessly supplied to the power consumption device disposed in the transfer module 2. Therefore, since the power supply state of the first coils 3 of the existing tile part 16 is controlled by providing the second coil 6 in the transfer module 2, the wireless power supply can be performed by changing the software without changing hardware.
(133) Further, the power can be wirelessly supplied to the power consumption device while the transfer module 2 is moving above the moving surface 15. Therefore, it is possible to detect the free movement of the transfer module 2 in the X, Y, Z, and directions, and also possible to perform the wireless power supply in real time in the moving area of the transfer module 2.
(134) Further, in the first coils 3 of the tile part 16, the power supply state of the first coils 3 corresponding to the positions of the magnets 4 of the transfer module 2 are switched to the driving mode, the power supply state of the first coil 3 corresponding to the position of the second coil 6 is switched to the wireless power supply mode, and the power supply state of the other first coils 3 is switched to the standby mode for the other first coils 3. The coils are arranged in the tile part 16 to cover the entire movable range of the transfer module 2, and only the first coils 3 directly below the main body 21 are used for levitating and moving the transfer module 2.
(135) Therefore, there is no need to provide a new coil for wireless power supply, and the movement of the transfer module 2 and the wireless power supply can be performed simultaneously using the existing tile part 16. Since both the transfer operation for the wafer W by the transfer module 2 and the wireless power supply can be achieved, the power can be supplied while suppressing a decrease in the throughput.
(136) Further, the second coil 6 and the magnets 4 disposed at the main body 21 are arranged without overlapping each other when viewed from the moving surface 15. Therefore, the driving of the main body 21 using the magnets 4 and the wireless power supply using the second coil 6 can be performed independently while suppressing mutual interference.
(137) Further, in the case of supplying an AC power to the first coils 3 of the tile part 16, the frequency is controlled depending on the moving speed of the transfer module 2. Accordingly, even if the moving speed changes during the translational movement of the transfer module 2, the variation in the electromotive force is suppressed. In addition, the magnitude of the AC power is controlled depending on the rotation angle of the transfer module 2. Hence, the variation in the electromotive force is also suppressed during the rotational movement of the transfer module 2. Accordingly, the power can be transmitted in a state where the variation in the electromotive force is suppressed at any location in the moving area of the transfer module 2, and the wirelessly power supply with high stability can be performed in real time during the movement of the transfer module 2.
(138) Even in the case of providing the battery 52 that stores the power supplied through the second coil 6, the battery 52 stores the power of the sensor 51 in the above embodiment. Therefore, there is no need to provide a large-capacity battery, and a small and lightweight battery 52 can be used. Hence, even if the battery 52 is disposed at the transfer module 2, the movement performance of the transfer module 2 is unlikely to be affected.
(139) <Another Example of Second Coil>
(140) Next, another example of the second coil will be described with reference to
(141)
(142)
(143) In these examples, the second coils 81 and 84 are arranged without overlapping the magnets 4 disposed at the main body 21 when viewed from the moving surface 15. Therefore, by switching the power supply state for each of the first coils 3 disposed at the tile part 16 to the driving mode, the wireless power supply mode, and the standby mode, the movement of the transfer module 2 and the wireless power supply to the sensors 51 disposed at the transfer module 2 can be performed.
(144) <Another Example of First Coil>
(145) Further, the first coil disposed at the tile part 16 is not limited to the above example. For example, a plurality of coils arranged in the tile part 16 to extend in different directions along the moving surface 15 when viewed from the vertical axis intersecting with the moving surface 15 may have the configuration shown in
(146) The tile part 16 in the example shown in
(147) In this example, the transfer module 2 can wirelessly supply a power to the power consuming devices disposed at the transfer module 2 by using the electromotive force that exerts against the magnetic field generated by the A coils, the B coils, the C coils, and the D coils disposed at the tile part 16.
(148) Further, in the wireless power supply mode, the power supplied to the first coils 3 disposed at the tile part 16 may be a DC power as well as an AC power.
(149) In this configuration, a group 1 in which a current of the I.sub.X direction is supplied to multiple coils and a group 2 in which a current of the I.sub.X direction is supplied to multiple coils are set for the A coils 31, for example. The groups 1 and 2 are arranged alternately in the X direction.
(150) When the transfer module 2 is moved in translation in the X direction at the moving speed V.sub.M, the direction of the magnetic flux B penetrating through the second coil 6 when the second coil 6 passes through the area of the group 1 and that when the second coil 6 passed through the area of the group 2 are different, as shown by the arrows in
(151) As described above, in the present disclosure, a driving coil for driving the transfer module 2, which serves as the first coil 3 disposed at the tile part 16, and a second coil for wireless power supply may be separately provided at the tile part 16. In this case, it is not necessary to switch the power supply state of the first coils 3 to the driving mode, the wireless power supply mode, or the standby mode, so that the control becomes easy.
(152) The power consuming devices provided in the transfer module 2 may be a camera or an electromagnet, if the magnet disposed at the main body 21 is an electromagnet, in addition to various sensors 51 such as the position sensor 511 and the inclination sensor 512 as described above.
(153) Further, it is not necessary to provide the battery 52 in the transfer module 2, and the electromotive force obtained in the second coil 6 may be converted into a DC power by the AC/DC conversion circuit 721 and then directly supplied to the sensors 51.
(154) When the battery 52 is provided, the electromotive force obtained in the second coil 6 can be stored. Thus, when the transfer module 2 is moving above the moving surface 15, it is not necessary to set the power supply state of the first coils 3 of the tile part 16 corresponding to the second coil 6 to the wireless power supply mode. For example, when a large amount of power is stored in the battery 52, the sensors 51 may be driven by the power supplied from the battery 52 without wirelessly supplying a power to the second coil.
(155) As described above, when an AC power is supplied to the first coils 3, an AC electromotive force acts between the first coils 3 and the second coil 6. Therefore, an electromotive force is generated not only when the transfer module 2 is moving above the moving surface 15, but also when the transfer module 2 is stopped. Hence, when the battery 52 is provided, the electromotive force obtained by the second coil 6 may be stored when the transfer module 2 is stopped, for example, when the transfer module 2 stands by for the transfer of the wafer W. Further, while the transfer module 2 is moving to transfer the wafer W, the sensors 51 may be driven by the power supplied from the battery 52 without wirelessly supplying a power to the second coil 6.
(156) Further, the coil disposed at the tile part 16 is not limited to the above example, and may vary as long as the magnetic field can be generated at the moving surface 15 of the substrate transfer chamber 14 by power supply. For example, a coil wound in a spiral shape around a vertical axis may be used, for example.
(157) Although an example in which addresses are assigned to the tile units T constituting the tile part 16, and a common address between the tile units T is assigned to the A coils 31 and the B coils 32 in the tile unit T has been described, the present disclosure is not limited to this example, and different coil addresses are assigned to all the A coils 31 and the B coils 32 arranged on the entire moving surface 15 of the substrate transfer chamber 14 and the coils to be set to the respective modes in the power supply state may be selected based on the coil addresses.
(158) Further, the substrate processing chamber 11 does not necessarily process a wafer in a vacuum atmosphere, and may process a wafer in an atmospheric pressure atmosphere. Therefore, the substrate transfer chamber 14 may be maintained in an atmospheric pressure atmosphere.
(159) Further, the main body 21 of the transfer module 2 does not necessarily have a rectangular shape in plan view, and may have a circular shape in plan view.
(160) It should be noted that the embodiments of the present disclosure are considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, replaced, or changed in various forms without departing from the scope of the appended claims and the gist thereof.