JP2017054880A - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of improving the uniformity of processing in the circumferential direction of a substrate, when processing a substrate placed on one side of a turntable while revolving, by rotating the turntable.SOLUTION: A substrate processing apparatus is constituted to include a mounting table for mounting a substrate provided rotatably on a turntable, a rotating body provided below the mounting table and rotating together therewith, a plurality of magnetic poles arranged in the circumferential direction of the rotating body, an electromagnet group provided independently from the turntable, and forming a magnetic pole group for driving the rotating body where multiple magnetic poles are arranged in the circumferential direction of the turntable, and a power supply for supplying a current to the coil of the electromagnet so that the rotating body rotates by a magnetic force between magnetic poles arranged in the rotating body and each magnetic pole of the magnetic pole group for driving the rotating body. Consequently, revolution and rotation of the rotating body are carried out independently.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a technical field in which processing is performed by supplying a processing gas to a substrate while revolving the substrate.

  In the manufacturing process of a semiconductor device, for example, ALD (Atomic Layer Deposition) is performed in order to form various films for forming an etching mask or the like on a semiconductor wafer as a substrate (hereinafter referred to as a wafer). . In order to increase the productivity of semiconductor devices, the above ALD revolves a rotating table on which a plurality of wafers are placed, revolves the wafer, and is disposed along the radial direction of the rotating table. May be performed by a device that repeatedly passes through the supply region (processing region). In addition, CVD (Chemical Vapor Deposition) may be performed in order to form each of the above-mentioned films, but this CVD film formation can also be performed by revolving the wafer in the same manner as the above-mentioned ALD. Conceivable.

  Incidentally, in such a film forming process for revolving a wafer, it is required to form a film with high uniformity in the circumferential direction of the wafer. Accordingly, it is required to form a film with high uniformity on the entire surface of the wafer W by forming a concentric film thickness distribution on the wafer W or forming a film with high uniformity in the radial direction of the wafer. . More specifically, the concentric film thickness distribution is the same or substantially the same film thickness at each position along the circumferential direction of the wafer that is equidistant from the center of the wafer. The film thickness distribution has different film thicknesses at each position along the radial direction.

  However, in the film forming apparatus that revolves the wafer, since the processing gas is supplied along the radial direction of the turntable, the film thickness distribution formed on the wafer varies from the center side to the peripheral side of the turntable. There is a tendency that the film thickness distribution changes as it goes, and it is difficult to form a highly uniform film thickness distribution in the circumferential direction of the wafer. Patent Document 1 discloses a film forming apparatus that forms the above-mentioned concentric film thickness distribution by forming a predetermined temperature distribution in the surface of a wafer and performing CVD. In this case, the wafer does not revolve during the film forming process. Therefore, Patent Document 1 cannot solve the above problem.

JP 2009-170822 A

  The present invention has been made under such circumstances, and an object of the present invention is to process gas with respect to the substrate while revolving the substrate placed on one side of the rotary table by rotating the rotary table. Is to provide a technique capable of improving the uniformity of the processing in the circumferential direction of the substrate.

In the substrate processing apparatus of the present invention, a substrate is placed on one surface side of a rotary table provided in a processing container, and a processing gas is supplied to the substrate while rotating the rotary table to revolve the substrate. In the substrate processing apparatus for processing
A rotation table provided on the rotary table so as to be rotatable, and a mounting table for mounting the substrate;
A rotating body provided below the mounting table and rotating together with the mounting table;
A plurality of magnetic poles arranged along the circumferential direction of the rotating body;
An electromagnet group that is provided independently of the rotary table and forms a magnetic pole group for driving a rotating body in which a plurality of magnetic poles are arranged along the circumferential direction of the rotary table;
A power supply unit for supplying a current to the coil of the electromagnet so that the rotating body rotates by a magnetic force between the magnetic pole arranged on the rotating body and each magnetic pole of the magnetic pole group for driving the rotating body; It is characterized by having.

  The present invention provides a rotating body that rotates together with a mounting table when a processing gas is supplied to the substrate while processing the substrate placed on one side of the rotating table by rotating the rotating table. A plurality of magnetic poles are arranged. An electromagnet group that forms a magnetic pole group for driving the rotating body is provided along the circumferential direction of the rotary table independently of the rotary table, and a magnetic force between the magnetic pole on the rotating body side and the magnetic pole group for driving the rotating body is provided. Current is supplied to the electromagnet so that the rotating body rotates. Accordingly, since the substrate can be rotated independently of the rotation of the turntable, the processing uniformity can be improved in the circumferential direction of the substrate.

It is a vertical side view of the film-forming apparatus which concerns on embodiment of the substrate processing apparatus of this invention. It is a cross-sectional top view of the said film-forming apparatus. It is a perspective view of the vacuum container of the said film-forming apparatus. It is an upper surface side perspective view of the turntable provided in the film-forming apparatus. It is a lower surface side perspective view of the turntable provided in the said film-forming apparatus. It is a top view of the magnetic drive unit and magnetic gear provided in the said film-forming apparatus. It is a top view of the plate which comprises the said magnetic drive unit. It is a perspective view of the said plate and a magnetic gear. It is a circuit diagram of the power supply part which comprises the said magnetic drive unit. It is explanatory drawing which shows the connection of the said power supply part and the coil wound around a plate. It is explanatory drawing which shows the connection of the said power supply part and the coil wound around a plate. It is explanatory drawing which shows the connection of the said power supply part and the coil wound around a plate. It is a graph which shows a three-phase alternating current and the change of the magnetic pole of the said plate. It is a graph which shows a three-phase alternating current and the change of the magnetic pole of the said plate. It is an effect | action figure which shows operation | movement of the said magnetic gear. It is an effect | action figure which shows operation | movement of the said magnetic gear. It is an effect | action figure which shows operation | movement of the said magnetic gear. It is an effect | action figure which shows a mode that film-forming is performed to a wafer. It is an effect | action figure which shows a mode that film-forming is performed to a wafer. It is an effect | action figure which shows a mode that film-forming is performed to a wafer. It is an effect | action figure which shows a mode that film-forming is performed to a wafer. It is explanatory drawing which shows the flow of each gas supplied in the said vacuum vessel. It is a schematic diagram which shows the result of an evaluation test. It is a schematic diagram which shows the result of an evaluation test. It is a graph which shows the result of an evaluation test. It is a graph which shows the result of an evaluation test. It is a graph which shows the result of an evaluation test. It is a graph which shows the result of an evaluation test.

A film forming apparatus 1 that performs ALD on a wafer W as a substrate, which is an embodiment of the substrate processing apparatus of the present invention, will be described. The film forming apparatus 1 adsorbs a BTBAS (Bistal Butylaminosilane) gas as a source gas, which is a processing gas containing Si (silicon), on the wafer W, and oxidizes ozone (O 2) as an oxidizing gas to oxidize the adsorbed BTBAS gas. ₃ ) A gas is supplied to form a molecular layer of SiO ₂ (silicon oxide), and the molecular layer is exposed to plasma generated from a plasma generating gas in order to modify the molecular layer. This series of processes is repeated a plurality of times to form a SiO ₂ film.

  FIG. 1 and FIG. 2 are a longitudinal side view and a transverse plan view of the film forming apparatus 1. The film forming apparatus 1 includes a substantially circular flat vacuum container (processing container) 11 and a disk-shaped horizontal rotary table (susceptor) 2 provided in the vacuum container 11. The vacuum container 11 includes a top plate 12 and a container body 13 that forms the side wall and bottom of the vacuum container 11.

  A central shaft 21 that extends vertically downward from the center of the turntable 2 is provided. The central shaft 21 is connected to a revolving rotation drive unit 22 provided so as to close an opening formed at the bottom of the container body 13. The turntable 2 is supported in the vacuum vessel 11 via the center shaft 21 and the revolution rotation drive unit 22 and rotates clockwise in plan view. In FIG. 1, reference numeral 15 denotes a gas nozzle that discharges N2 (nitrogen) gas into the gap between the central shaft 21 and the container main body 13, and N2 gas is discharged during processing of the wafer W to move from the front surface to the back surface of the turntable 2. It has a role to prevent wraparound of raw material gas and oxidizing gas.

  Further, on the lower surface of the top plate 12 of the vacuum vessel 11, a center region forming portion C having a circular shape in plan view protruding so as to face the center portion of the turntable 2, and from the center region forming portion C to the outside of the turntable 2. Projection portions 17 and 17 having a fan-like shape in plan view and formed so as to spread toward the top are formed. That is, the central region forming portion C and the protruding portions 17 and 17 constitute a lower ceiling surface than the outer region. The gap between the central region forming part C and the central part of the turntable 2 constitutes the N2 gas flow path 18. During processing of the wafer W, N 2 gas is supplied from the gas supply pipe connected to the top plate 12 to the flow path 18, and is discharged from the flow path 18 toward the entire outer periphery of the turntable 2. This N 2 gas prevents the source gas and the oxidizing gas from coming into contact with each other on the center portion of the turntable 2.

  FIG. 3 is a perspective view showing a bottom surface inside the container body 13. A flat ring-shaped recess 31 is formed in the container main body 13 along the circumference of the turntable 2 below the turntable 2. A ring-shaped slit 32 is formed in the bottom surface of the recess 31 along the circumferential direction of the recess 31, and the slit 32 is formed so as to penetrate the bottom of the container body 13 in the thickness direction. ing. Further, on the bottom surface of the recess 31, a heater 33 for heating the wafer W placed on the turntable 2 is arranged in seven rings. In FIG. 3, in order to avoid complication, a part of the heater 33 is cut out.

  The heaters 33 are arranged along concentric circles centering on the rotation center of the turntable 2, and four of the seven heaters 33 are inside the slit 32 and the other three are outside the slit 32. Is provided. The space in the recess 31 where the heater 33 is provided is purged by supplying N 2 gas from a gas nozzle (not shown). Moreover, the shield 34 is provided so that the upper side of each heater 33 may be covered and the upper side of the recessed part 31 may be plugged up (refer FIG. 1). The shield 34 is provided with a ring-shaped slit 32A so as to overlap the slit 32, and a rotating shaft 26 and a column 41, which will be described later, penetrate the slit 32A. Further, exhaust ports 35 and 36 for exhausting the inside of the vacuum container 11 are opened outside the recess 31 on the bottom surface of the container body 13. An exhaust mechanism 39 configured by a vacuum pump or the like is connected to the exhaust ports 35 and 36.

  Next, the turntable 2 will be described with reference to FIGS. 4 and 5 showing the front side and the back side, respectively. On the front surface side (one surface side) of the turntable 2, five circular recesses are formed along the rotation direction of the turntable 2, and a circular wafer holder 24 is provided in each recess. A recess 25 is formed on the surface of the wafer holder 24, and the wafer W is horizontally stored in the recess 25. Therefore, the wafer holder 24 serves as a mounting table for the wafer W, and the bottom surface of the recess 25 constitutes a mounting area for the wafer W.

  For example, three struts 41 are extended vertically downward from positions separated from each other in the circumferential direction of the back surface of the turntable 2, and the lower ends of the respective struts 41 are formed through slits 32 as shown in FIG. The bottom of the container body 13 is penetrated and connected to a support ring 42 which is a connection part provided below the container body 13. The support ring 42 is formed along the rotation direction of the turntable 2, is provided horizontally so as to be suspended from the container body 13 by the support column 41, and rotates together with the turntable 2.

  Further, a rotating shaft 26 that is a rotating body that rotates together with the wafer holder 24 extends vertically downward from a central portion below the wafer holder 24. The lower end of the rotary shaft 26 penetrates the rotary table 2, penetrates the bottom of the container body 13 through the slit 32 as shown in FIG. 1, and further penetrates the support ring 42 and the bearing unit 27 to form the magnetic gear 28. It is connected.

  The bearing unit 27 is provided on the support ring 42 and includes a bearing for rotating the rotating shaft 26 and a magnetic seal for preventing particles from scattering from the bearing. The magnetic gear 28 is a magnet configured in a horizontal ring shape surrounding the rotating shaft 26, and is configured by alternately arranging, for example, four S poles and N poles in the circumferential direction. Since the wafer holder 24 and the rotary shaft 26 are configured as described above, the magnetic gear 28 is configured to be suspended from the rotary table 2, and the rotation center of the rotary table 2 is rotated by the rotation of the rotary table 2. Rotates as the center, ie revolves. As the rotary table 2 rotates, the wafer W placed on the wafer holder 24 of the rotary table 2 revolves in the same manner as the magnetic gear 28.

  In FIG. 1, reference numeral 43 denotes a partition that is provided below the container body 13 so as to surround the support ring 42, the bearing unit 27, and the magnetic gear 28, and partitions these from the outside of the vacuum container 11. In this example, the partition wall 43 is formed in a concave shape in cross section. The region surrounded by the partition wall 43 is configured such that, for example, purge gas is supplied from a gas supply nozzle (not shown), and even if particles are generated from the bearing unit 27, they are removed from the partition wall 43.

  At the bottom of the partition wall 43, the magnetic drive unit 4 is provided below the moving path of the magnetic gear 28. FIG. 6 is a plan view of the magnetic drive unit 4, and FIGS. 7 and 8 are a plan view and a perspective view showing a part of the magnetic drive unit 4, respectively. The magnetic drive unit 4 and the magnetic gear 28 will be further described with reference to FIGS.

  P1 in FIG. 6 indicates the central axis of rotation of the turntable 2, and the magnetic gear 28 revolves so as to go around the central axis P1. In this orbit, the magnetic gears 28 are arranged at equal intervals. The magnetic drive unit 4 includes, for example, 240 upstanding plates 45. Each plate 45 is disposed below the orbit of the magnetic gear 28 along the orbit. Each plate 45 is provided so that the length direction of each plate 45 is along the diameter of the turntable 2.

  The plate 45 is formed in a generally concave shape when viewed from the side. By being configured in such a concave shape, one plate 45 includes two standing plates 46A and 46B. A standing plate near the central axis P1 is shown as 46A, and a standing plate opposite to the central axis P1 side is shown as 46B. The standing plates 46A and 46B are each configured as an individual electromagnet. The upper side of each of the standing plates 46A, 46B is configured as an electromagnet magnetic pole 47A, 47B. The magnetic poles 47A, 47B are horizontally directed from the standing plate 46A, 46B toward the center in the length direction of the plate 45, respectively. It is formed to extend slightly. The magnetic pole 47A of each plate 45 constitutes an inner magnetic pole group, and the magnetic pole 47B constitutes an outer magnetic pole group. Further, the plate 45 is not rotated by the rotation of the turntable 2. That is, the plate 45 is provided independently of the turntable 2.

  Coils 48A and 48B are wound around the standing plates 46A and 46B, respectively. As will be described later, current is supplied to the coils 48A and 48B so that the polarities of the magnetic poles 47A and 47B are switched over time. As a result, the magnetic gear 28 rotates in the circumferential direction and horizontally around the central axis of the magnetic gear 28. The rotation of the magnetic gear 28 causes the wafer holder 24 connected to the magnetic gear 28 to rotate, and the wafer W placed on the wafer holder 24 rotates in the horizontal direction around the center thereof. The rotation of the wafer W and the rotation of the magnetic gear 28 may be described as rotation in order to distinguish from the above revolution.

  Below the plate 45, ring-shaped power supply units 51A and 51B are provided, respectively, and the power supply unit 51A is located inside the power supply unit 51B. Each coil 48A is supplied with a current from a power supply unit 51A that is a first power supply unit, and each coil 48B is supplied with a current from a power supply unit 51B that is a second power supply unit. The power supply units 51A and 51B are configured in the same manner except for the positions where they are arranged. Here, the power supply unit 51A will be described as a representative. The power supply unit 51A is a three-phase AC power supply, and has a so-called Δ connection as shown in FIG. 9, for example, and can supply currents whose phases are shifted by 120 °. The phases of each current are described as R phase, S phase, and T phase, respectively. In FIG. 9, the terminals for taking out the current of each phase from the Δ connection are shown as 52, 53, and 54.

  10 to 12 show connections between the coils 48A and 48B of each plate 45 and the terminals 52 to 54 of the power supply units 51A and 51B. The coils 48A and 48B of each plate 45 are connected to the power supply units 51A and 51B as shown in any of FIGS. As shown in FIGS. 10, 11 and 12, the plate 45 to which the coils 48A and 48B are connected may be described as 45A, 45B and 45C. The terminals 52 and 53 of the power supply unit 51A are connected to both ends of the coil 48A of the plate 45A in FIG. 10, and the terminals 52 and 53 of the power supply unit 51B are connected to both ends of the coil 48B of the plate 45A. . By connecting in this way, R-phase current is supplied to the coils 48A and 48B of the plate 45A.

  11, terminals 52 and 53 of the power supply unit 51A are connected to both ends of the coil 48A of the plate 45B, and terminals 52 and 53 of the power supply unit 51B are connected to both ends of the coil 48B of the plate 45B. . By being connected in this way, an S-phase current is supplied to the coils 48A and 48B of the plate 45B. The terminals 52 and 53 of the power supply unit 51A are connected to both ends of the coil 48A of the plate 45C in FIG. 12, and the terminals 52 and 53 of the power supply unit 51B are connected to both ends of the coil 48B of the plate 45C. . By connecting in this way, a T-phase current is supplied to the coils 48A and 48B of the plate 45C.

  When the magnetic pole 47A of the plate 45A, the magnetic pole 47A of the plate 45B, and the magnetic pole 47A of the plate 45C are a set of magnetic poles 47A, 80 sets of the magnetic poles 47A are provided. If the magnetic pole 47B of the plate 45A, the magnetic pole 47B of the plate 45B, and the magnetic pole 47B of the plate 45C are a set of magnetic poles 47B, 80 sets of the magnetic poles 47B are provided. When viewed in the arrangement direction of the plates 45, the three plates 45A, the three plates 45B, and the three plates 45C are repeatedly arranged in this order.

  Returning to FIGS. 1 to 3, the configuration of the film forming apparatus 1 other than the magnetic drive unit 4 will be described. A transfer port 37 for the wafer W and a gate valve 38 for opening and closing the transfer port 37 are provided on the side wall of the container body 13 (see FIG. 2), and a transfer mechanism that enters the vacuum vessel 11 through the transfer port 37. The wafer W is transferred between the recess 25 and the recess 25. Specifically, through holes are formed at positions corresponding to each other on the bottom surface of the recess 25, the bottom of the container body 13 and the turntable 2, and the tip of the pin is located on the recess 25 and the container body via each through hole. 13 is configured to move up and down. The wafer W is transferred via these pins. The illustration of this pin and the through hole of each part through which the pin penetrates is omitted.

  Further, as shown in FIG. 2, on the turntable 2, the source gas nozzle 61, the separation gas nozzle 62, the oxidizing gas nozzle 63, the plasma generating gas nozzle 64, and the separation gas nozzle 65 are spaced in this order in the rotation direction of the turntable 2. Arranged. Each of the gas nozzles 61 to 65 is formed in a rod shape extending horizontally along the diameter of the rotary table 2 from the side wall of the vacuum vessel 11 toward the center, and gas is discharged from a number of discharge ports 66 formed along the diameter. Is discharged downward.

  The raw material gas nozzle 61 constituting the processing gas supply mechanism discharges the above-described BTBAS (Bistal Butylaminosilane) gas. In the figure, reference numeral 67 denotes a nozzle cover that covers the source gas nozzle 61, and is formed in a fan shape that spreads from the source gas nozzle 61 toward the upstream side and the downstream side in the rotation direction of the turntable 2. The nozzle cover 67 has a role of increasing the concentration of the BTBAS gas below the nozzle cover 67 to increase the adsorption property of the BTBAS gas to the wafer W. The oxidizing gas nozzle 63 discharges the ozone gas. The separation gas nozzles 62 and 65 are gas nozzles that discharge N 2 gas, and are arranged so as to divide the fan-shaped protrusions 17 and 17 of the top plate 12 in the circumferential direction.

The plasma generating gas nozzle 64 discharges a plasma generating gas made of, for example, a mixed gas of argon (Ar) gas and oxygen (O ₂ ) gas. The top plate 12 is provided with a fan-shaped opening along the direction of rotation of the turntable 2, and a cup shape made of a dielectric material such as quartz corresponding to the shape of the opening so as to close the opening. The plasma forming unit 71 is provided. The plasma forming portion 71 is provided between the oxidizing gas nozzle 63 and the protruding portion 17 when viewed in the rotation direction of the turntable 2. In FIG. 2, the position where the plasma forming unit 71 is provided is indicated by a chain line.

  On the lower surface of the plasma forming portion 71, a protrusion 72 is provided along the peripheral edge of the plasma forming portion 71, and the tip of the plasma generating gas nozzle 64 is surrounded by the protrusion 72. The protrusion 72 is penetrated from the outer peripheral side of the turntable 2 so that gas can be discharged to the region. The protrusion 72 has a role of suppressing the entry of N 2 gas, ozone gas, and BTBAS gas below the plasma forming unit 61 and suppressing a decrease in the concentration of the plasma generating gas.

  A depression is formed on the upper side of the plasma forming portion 71, and a box-shaped Faraday shield 73 that opens upward is disposed in the depression. On the bottom surface of the Faraday shield 73, an antenna 75 in which a metal wire is wound around a vertical axis in a coil shape is provided via an insulating plate member 74. A high frequency power source 76 is connected to the antenna 75. ing. The bottom surface of the Faraday shield 73 is a slit 77 for preventing the electric field component of the electromagnetic field generated in the antenna 75 from being directed downward when a high frequency is applied to the antenna 75 and for directing the magnetic field component downward. Is formed. The slits 77 extend in a direction perpendicular to (intersect) the winding direction of the antenna 75, and a large number of slits 77 are formed along the winding direction of the antenna 75. By configuring each unit in this way, when the high frequency power supply 76 is turned on and a high frequency is applied to the antenna 75, the plasma generating gas supplied below the plasma forming unit 71 can be turned into plasma.

On the turntable 2, the lower region of the nozzle cover 67 of the source gas nozzle 61 is an adsorption region R1 where the BTBAS gas that is the source gas is adsorbed, and the lower region of the oxidizing gas nozzle 63 is oxidized with the BTBAS gas by ozone gas. This is referred to as oxidized region R2. Further, a region below the plasma forming unit 71 is a plasma forming region R3 in which the SiO ₂ film is modified by plasma. The lower region of the protrusions 17 and 17 is separated in order to separate the adsorption region R1 and the oxidation region R2 from each other by the N2 gas discharged from the separation gas nozzles 62 and 65, thereby preventing mixing of the source gas and the oxidation gas. Regions D and D are configured, respectively.

  The exhaust port 35 is opened to the outside between the adsorption region R1 and the separation region D adjacent to the adsorption region R1 on the downstream side in the rotation direction, and exhausts excess BTBAS gas. The exhaust port 36 is opened outside the vicinity of the boundary between the plasma formation region R3 and the separation region D adjacent to the plasma formation region R3 on the downstream side in the rotation direction, and is used for generating excess O3 gas and plasma. Exhaust the gas. From each exhaust port 35, 36, N 2 gas supplied from each separation region D, the gas supply pipe 15 below the turntable 2, and the center region forming portion C of the turntable 2 is also exhausted. In FIG. 1, 39 is a vacuum pump connected to the exhaust ports 35 and 36.

  The film forming apparatus 1 is provided with a control unit 100 including a computer for controlling the operation of the entire apparatus (see FIG. 1). The control unit 100 stores a program for executing a film forming process as will be described later. The program controls the operation of each unit by transmitting a control signal to each unit of the film forming apparatus 1. Specifically, the supply flow rate of each gas from each gas nozzle 61 to 65, the temperature of the wafer W by the heater 33, the supply flow rate of N 2 gas from the gas supply pipe 15 and the center region forming unit C, the revolution rotation drive unit 22. The rotational speed of the rotary table 2 by the above and the rotational speed of the wafer holder 24 by the magnetic drive unit 4 are controlled according to the control signal. In the above program, these controls are performed, and a group of steps is set so that each process described later is executed. The program is installed in the control unit 100 from a storage medium such as a hard disk, a compact disk, a magneto-optical disk, a memory card, or a flexible disk. The control unit 100 sets a difference between the phase of each current supplied to the magnetic pole 47A group and the phase of each current supplied to the magnetic pole 47B group, and causes the magnetic gear 28 to operate as described later. It is also a setting part.

  Subsequently, the supply of current to the plates 45A to 45C and the operation of the magnetic gear 28 will be described with reference to FIGS. 13 and 14 show waveforms of R-phase, S-phase, and T-phase currents supplied to the coils 48A and 48B of the plates 45A to 45C. More specifically, the graph 81 shows the current of each phase supplied to the coil 48A of the plates 45A to 45C, and the graph 82 shows the current of each phase supplied to the coil 48B of the plates 45A to 45C. . In the graphs 81 and 82, the R-phase current is indicated by a solid line, the S-phase current is indicated by a dotted line, and the T-phase current is indicated by a chain line.

  The horizontal axes of the graphs 81 and 82 indicate time. The vertical axes of the graphs 81 and 82 represent the magnitude of the current and the sign of the current, and the N pole and the S pole of the magnetic poles 47A and 47B of the plates 45A to 45C are switched according to the change in the current. In this example, when the current is +, the magnetic poles 47A and 47B are S poles, and when the current is-, the magnetic poles 47A and 47B are N poles. For convenience of illustration and explanation, the horizontal axes of the graphs 81 and 82 are indicated by dotted line scales at predetermined time intervals, and the scales attached during one cycle are shown from the left side to the right side of the horizontal axis. On the other hand, numbers 1 to 12 are shown as circled numbers. In the following description of the operation of the magnetic gear 28, the time in the graph may be represented by this number.

(When the magnetic gear 28 rotates without revolving)
FIG. 15 shows the state of the magnetic gear 28 in association with the graphs 81 and 82 for the operation when the magnetic gear 28 rotates without revolving. FIG. 15 shows the magnetic gear 28 and the plates 45A to 45C positioned below the magnetic gear 28 in the columns A1 to A12. About this column A1-A12, it shows that it is a state later in time, so that the number attached | subjected after A is large. The numbers given as circled numbers on the magnetic pole 47A side in each column correspond to the time numbers in the graph 81 and indicate that the current of each phase is supplied as indicated by the time numbers. . In addition, the numbers given as circled numbers on the magnetic pole 47B side in each column correspond to the time numbers in the graph 82, and the current of each phase is supplied as indicated by the time numbers. Indicates. Further, regarding the polarities of the magnetic pole 47A and the magnetic pole 47B, circles and x marks are added to the virtual circles shown on the magnetic pole 47A and the magnetic pole 47B, respectively, to indicate that they are S and N poles, respectively. .

  Further, for convenience of explanation, the magnetic poles 28A to 28H are sequentially shown in the circumferential direction for the magnetic gear 28 in each column. The magnetic poles 28A, 28C, 28E, and 28G are N poles, and the magnetic poles 28B, 28D, 28F, and 28H are S poles. In addition, an arrow pointing in the direction of the magnetic pole 28E is displayed at the center of the magnetic gear 28 in order to indicate the direction of the magnetic gear 28. In addition, in order to prevent complication of the drawing, the plate 45 is shown as being arranged in a straight line.

  With the rotation of the turntable 2 stopped, the current of each phase changes so that the horizontal axes of the graphs 81 and 82 are directed to the right. The cycle of the current supplied to the coil 48A and the cycle of the current supplied to the coil 48B are controlled to be equal to each other. In the column A1 of FIG. 15, the magnetic poles 47A and 47B are in the state shown at time 1 in the graph 81 and the graph 82, respectively. That is, the R-phase current has a maximum value of +, the S-phase and T-phase currents have a minus value, and have the same value. Therefore, the magnetic poles 47A and 47B of the plate 45A are S poles, and the magnetic poles 47A and 47B of the plate 45B and the magnetic poles 47A and 47B of the plate 45C are N poles.

  The magnetic poles 28B, 28A, 28H, 28D, 28E, and 28F of the magnetic gear 28 are attracted by the magnetic forces of the magnetic poles 47A and 47B, so that the magnetic pole 47A of the plate 45C, the magnetic pole 47A of the plate 45A, and the plate It is located on the magnetic pole 47A of 45B, the magnetic pole 47B of the plate 45C, the magnetic pole 47B of the plate 45A, and the magnetic pole 47B of the plate 45B, respectively.

  From the state indicated by the column A1, the R-phase and T-phase currents decrease and the S-phase current increases for the magnetic pole 47A group, and the R-phase and T-phase currents decrease and the S-phase current decreases for the magnetic pole 47B group. The current increases. As a result, the magnetic pole 47A of the plate 45C and the magnetic pole 47B of the plate 45B become nonpolar (time 2 of the column A2, graphs 81 and 82), and thereafter become the S pole. As a result, the magnetic pole 28E, which is the N pole of the magnetic gear 28, is attracted to the magnetic pole 47B of the plate 45B, and the magnetic pole 28A, which is the N pole of the magnetic gear 28, is attracted to the magnetic pole 47A of the plate 45C. (Time A in column A3, graphs 81 and 82).

  Thereafter, for the magnetic pole 47A group, the R-phase current continues to decrease, the S-phase current increases from the minimum value, and the T-phase current continues to increase. For the magnetic pole 47B group, the R-phase current continues to decrease, the S-phase current continues to increase, and the T-phase current increases from the minimum value. As a result, the magnetic pole 47A and the magnetic pole 47B of the plate 45A become nonpolar (time A in column A4, graphs 81 and 82), and then become the N pole. As a result, the magnetic pole 28H, which is the S pole of the magnetic gear 28, is attracted to the magnetic pole 45A of the plate 45A, and the magnetic pole 28D, which is the S pole of the magnetic gear 28, is attracted to the magnetic pole 47B of the plate 45A. (Time A in column A5, graphs 81 and 82).

  Thereafter, for the magnetic pole 47A group, the R-phase current continues to decrease, the S-phase current continues to increase, and the T-phase current decreases from the maximum value. For the magnetic pole 47B group, the R-phase current continues to decrease, the S-phase current decreases from the maximum value, and the T-phase current continues to increase. As a result, the magnetic pole 47A of the plate 45B and the magnetic pole 47B of the plate 45C become nonpolar (time A in column A6, graphs 81 and 82), and then become the S pole. As a result, the magnetic pole 28G, which is the N pole of the magnetic gear 28, is attracted to the magnetic pole 47A of the plate 45B, and the magnetic pole 28C, which is the N pole of the magnetic gear 28, is attracted to the magnetic pole 47B of the plate 45C. Rotate around (time A in column A7, graphs 81, 82).

  Thereafter, the polarity of the magnetic poles 47A and 47B of the plates 45A to 45C changes due to the change in the current of the three-phase alternating current, and the magnetic poles 47A and 47B whose polarity has changed due to the magnetic force of the magnetic poles 47A and 47B whose polarity has changed. By pulling the magnetic poles of the magnetic gear 28 located in the vicinity, the magnetic gear 28 continues to rotate clockwise in plan view. The operation of the columns A8 to A12 will be briefly described. After the magnetic pole 47A of the plate 45C and the magnetic pole 47B of the plate 45B become non-polar (time 8 of the column A8, graphs 81 and 82), the magnetic poles 45A and 45B The magnetic poles 28D and 28H, which are the S poles of the magnetic gear 28, are attracted by the N pole (column A9, time 9 in the graphs 81 and 82).

  Subsequently, after the magnetic pole 47A and the magnetic pole 47B of the plate 45A have become nonpolar (time A in the column A10, graphs 81 and 82), these magnetic poles 45A and 45B become the S pole and are the N pole of the magnetic gear 28. The magnetic poles 28C and 28G are attracted (time A11 in the column A11 and the graphs 81 and 82). Thereafter, the magnetic pole 47A of the plate 45B and the magnetic pole 47B of the plate 45C become nonpolar (time A12 in the column A12, graphs 81 and 82). The polarities of the magnetic pole 47A group and the magnetic pole 47B group are returned to the state indicated by the column A1 after the state of the column A12, and thereafter, the change in polarity described in the columns A1 to A12 is repeated. Thereby, the rotation of the magnetic gear 28 is continued. When the power supply to the magnetic pole 47A group and the magnetic pole 47B group is stopped, the rotation of the magnetic gear 28 is stopped. The rotation speed of the magnetic gear 35 shown in FIG. 15 is controlled by controlling the current cycle of each phase.

(When the magnetic gear 28 revolves without rotating)
In FIG. 16, regarding the operation when the magnetic gear 28 revolves without rotating, the state of the magnetic gear 28 is shown in columns B <b> 1 to B <b> 9 corresponding to the graphs 81 and 82 as in FIG. 15. In this case, for the coil 48A of the plate 45, each current value is controlled so that the horizontal axis of the graph 81 is directed from the right side to the left side, and for the coil 48B of the plate 45, the horizontal axis of the graph 82 is directed from the left side to the right side. Thus, each current value is controlled. The cycle of the current supplied to the coil 48A is equal to the cycle of the current supplied to the coil 48B.

  First, in the column B1, the current is supplied to the magnetic pole 47A group and the magnetic pole 47B group as shown at time 1 in the graph 81 and the graph 82 as described in the column A1 in FIG. That is, the magnetic poles 47A and 47B of the plate 45A are S poles, and the magnetic poles 47A and 47B of the plate 45B and the magnetic poles 47A and 47B of the plate 45C are N poles. Of the magnetic poles 28A to 28H, the magnetic pole 28A is located closest to the center axis of the turntable 2, and the magnetic pole 28E is located closest to the periphery of the turntable 2. These magnetic poles 28A and 28E are the magnetic poles 47A of the plate 45A. , 47B, respectively.

  From the state of the column B1, the magnetic gear 28 revolves by the rotation mechanism 22 and moves above the magnetic poles 47A and 47B in a clockwise direction in plan view, and the R phase and the T phase for the magnetic poles 47A and 47B. As the current decreases, the S-phase current increases. As a result, the polarities of the magnetic poles 47A and 47B of the plate 45B below the traveling path of the magnetic poles 28A and 28E change from N pole to nonpolarity (column B2, time 12 at time 12 and 82 in the graph 81), and then S pole. At the same time, the magnetic poles 28A and 28E are positioned above the magnetic poles 47A and 47B of the plate 45B (column B3, time 11 of time 81 and time 3 of graph 81). The magnetic poles 28A and 28E are attracted to the magnetic poles 47A and 47B whose polarities have changed in this way, whereby the orientation of the magnetic gear 28 is maintained, that is, the magnetic gear 28 does not rotate.

  Thereafter, for the magnetic poles 47A and 47B, the decrease in the R-phase current and the increase in the S-phase current continue and the T-phase current increases from the minimum value, and the polarities of the magnetic poles 47A and 47B of the plate 45A become the S pole. From the time point to column N4 (column B4, time 10 of graph 81, time 4 of time 82), and then the polarity of N (column B5, time 9 of graph 81, time 5 of time 82). Thereafter, for the magnetic poles 47A and 47B, the R-phase current continues to decrease, the S-phase current decreases from the maximum value, and the T-phase current continues to increase. As a result, the polarities of the magnetic poles 47A and 47B of the plate 45C below the traveling path of the magnetic poles 28A and 28B change from the N pole to the nonpolarity (column B6, time 8 of the graph 81, time 6 of the time 82), and then the S pole. At the same time, the magnetic poles 28A and 28E are positioned above the magnetic poles 47A and 47B of the plate 45A (column B7, time 7 of graph 81, time 7 of time 82). The orientation of the magnetic gear 28 is maintained by attracting the magnetic poles 28A and 28E to the magnetic poles 47A and 47B whose polarities have changed in this way.

  Thereafter, for the magnetic poles 47A and 47B, the R-phase current increases from the minimum value, the S-phase current continues to decrease, the T-phase current continues to increase, and the polarities of the magnetic poles 47A and 47B of the plate 45B change. It becomes nonpolar from the S pole (column B8, time 8 at time 8 and 82 in the graph 81), and then changes to N pole (column B9, time 7 at time 82 in the graph 81, time 7 at 82).

  After the state shown in column B9, the polarities of the magnetic poles 47A and 47B of the plate 45A below the traveling path of the magnetic poles 28A and 28E change from the N pole to the nonpolarity due to the change in the current supplied to the magnetic poles 47A and 47B. When the magnetic poles 28A and 28E are positioned on the magnetic poles 47A and 47B of the plate 45A, they are set to the S pole. Thereby, the orientation of the magnetic gear 28 is maintained, and the magnetic gear 28 continues to revolve without rotating. Thereafter, the rotation of the rotary table 2 is stopped and the power supply to the magnetic poles 47A and 47B is stopped, whereby the revolution of the magnetic gear 28 that does not rotate is completed.

  By the way, for convenience of explanation, in the magnetic poles 47A and 47B, the explanation has centered on the polarity of the magnetic poles below the magnetic poles 28A and 28E, but as described above, the magnetic poles 47A and 47B in the revolving state of the magnetic gear 28 By controlling the supplied current, the magnetic poles 28B and 28H, which are S poles located on the center axis side of the turntable 2, and the magnetic poles 28D, 28F which are S poles located on the peripheral end side of the turntable 2 are below. The magnetic poles 47A and 47B located at the center are N poles. That is, of the magnetic poles 47A and 47B, the polarity of each magnetic pole is such that the magnetic poles located below the magnetic poles 28A and 28E are S poles, and the magnetic poles located below the magnetic poles 28B, 28H, 28D and 28F are N poles. Is controlled, the magnetic gear 28 can continue to revolve without rotating. In this way, when the magnetic gear 35 revolves without rotating, the current cycle is controlled according to the revolution speed of the magnetic gear 35.

(When the magnetic gear 28 revolves while rotating)
In FIG. 17, regarding the operation when the magnetic gear 28 revolves while rotating, the state of the magnetic gear 28 is shown in columns C <b> 1 to C <b> 9 corresponding to the graphs 81 and 82 as in FIG. 15. In this case, each current value is controlled so that the horizontal axis of the graph 82 is directed from the right side to the left side for the coil 48A of the plate 45, and the horizontal axis of the graph 82 is directed from the left side to the right side for the coil 48B of the plate 45. Each current value is controlled. The cycle of the current supplied to the coil 48A and the cycle of the current supplied to the coil 48B are different from each other, and the cycle of the current supplied to the coil 48B is shorter.

  First, in the state shown in the column C1, the current is supplied to the magnetic pole 47A group and the magnetic pole 47B group as shown at time 1 in the graph 81 and the graph 82, respectively, as described in the column A1 in FIG. That is, the magnetic poles 47A and 47B of the plate 45A are S poles, and the magnetic poles 47A and 47B of the plate 45B and the magnetic poles 47A and 47B of the plate 45C are N poles. The magnetic pole 28A and the magnetic pole 28E are positioned on the magnetic poles 47A and 47B of the plate 45A, respectively.

  From the state of the column C1, the magnetic gear 28 is revolved by the rotation mechanism 22 and moves clockwise above the magnetic poles 47A and 47B, and the R and T phases of the magnetic poles 47A and 47B As the current decreases, the S-phase current increases. As a result, the polarity of the magnetic pole 47A of the plate 45B changes from the N pole to the nonpolarity, and after the polarity of the magnetic pole 47B of the plate 45B changes from the N pole to the nonpolarity, the polarity changes to the S pole (column C2, time of graph 81). 12 and 82 between times 2-3). The polarity of the magnetic pole 47B of the plate 45B located immediately on the front side when viewed from the magnetic pole 28E that is the N pole of the magnetic gear 28 is changed to the S pole, and rearward when viewed from the magnetic pole 28A that is the N pole of the magnetic gear 28. Since the magnetic pole 47A of the plate 45A facing the S pole is still the S pole, the revolving magnetic gear 28 rotates clockwise in a plan view.

  Thereafter, for the magnetic pole 47A group, the R-phase and T-phase currents continue to decrease and the S-phase current increases. For the magnetic pole 47B group, the R-phase current continues to decrease, the S-phase current continues to increase, and the T-phase current decreases and rises after reaching a minimum value. As a result, the magnetic pole 47B of the plate 45A shifts from the S pole to the N pole (column C3, between time 11 and time 4-5 of the graph 81). The magnetic pole 47B of the plate 45A attracts the magnetic pole 28D which is the S pole located in the vicinity of the magnetic pole 47B in the magnetic gear 28, and the rotation of the magnetic gear 28 further proceeds.

  Thereafter, for the magnetic pole 47A group, the R-phase current continues to decrease, the S-phase current continues to increase, and the T-phase current increases from the minimum value. With respect to the magnetic pole 47B group, the R-phase current continues to decrease, decreases after the S-phase current reaches the maximum value, and the T-phase current increases. As a result, the magnetic pole 47A of the plate 45A and the magnetic pole 47B of the plate 45C become nonpolar (column C4, time 10 of the graph 81, time 6 of the graph 81). Subsequently, for the magnetic pole 47A group, the R-phase current continues to decrease, the S-phase current continues to increase, and the T-phase current continues to increase. Regarding the magnetic pole 47B group, the R-phase current increases after reaching a minimum value, the S-phase current continues to decrease, and the T-phase current continues to increase. Thereby, the magnetic pole 47A of the plate 45A becomes an N pole, and the magnetic pole 47B of the plate 45C becomes an S pole. The polarity of the magnetic pole 47B of the plate 45C located immediately on the front side when viewed from the magnetic pole 28E that is the N pole of the magnetic gear 28 is changed to the S pole, and the rear side when viewed from the magnetic pole 28A that is the N pole of the magnetic gear 28. Since the magnetic pole 47 </ b> A of the plate 45 </ b> B that is facing is still the S pole, the revolving magnetic gear 28 further rotates (between column C <b> 5 and time 7-8 of time 9 and 82 in the graph 81).

  Thereafter, for the magnetic pole 47A group, the R-phase current continues to decrease, the S-phase current decreases from the maximum value, and the T-phase current continues to increase. Regarding the magnetic pole 47B group, the R-phase current continues to increase, the S-phase current continues to decrease, and decreases after the T-phase current reaches the maximum value. As a result, the magnetic pole 47A of the plate 45C becomes non-polar, and the magnetic pole 47B of the plate 45B becomes N-pole (column C6, between time 8 and time 9-10 of the graph 81). For the magnetic pole 47A group, the R-phase and S-phase currents continue to decrease, and the T-phase current continues to increase. For the magnetic pole 47B group, the R-phase current continues to increase, the S-phase current continues to decrease and reaches a minimum value, and the T-phase current continues to decrease. Thereby, the magnetic pole 47A of the plate 45C becomes the S pole, and the magnetic pole 47B of the plate 45A becomes the S pole. The polarity of the magnetic pole 47B of the plate 45A located immediately on the front side when viewed from the magnetic pole 28E that is the N pole of the magnetic gear 28 is changed to the S pole, and rearward when viewed from the magnetic pole 28A that is the N pole of the magnetic gear 28. Because the magnetic pole 47A of the plate 45B facing toward the S pole is still the S pole, the revolving magnetic gear 28 further rotates, and the magnetic pole 28D that is the S pole moves closer to the peripheral end of the turntable 2 and the magnetic pole that is the S pole. 28H moves closer to the center axis of the turntable 2 (column C7, time 7 in the graph 81, time 11 in the 82).

  Thereafter, for the magnetic pole 47A group, the R-phase current increases from the minimum value, the S-phase current continues to decrease, and the T-phase current continues to increase. For the magnetic pole 47B group, the R-phase current continues to increase, the S-phase current increases from the minimum value, and the T-phase current continues to decrease. As a result, the magnetic pole 47A of the plate 45B becomes non-polar, and the magnetic pole 47B of the plate 45C becomes N-pole (column C8, time 6-1, time 12-1 of the graph 81). For the magnetic pole 47A group, the R-phase current continues to increase, the S-phase current continues to decrease, and the T-phase current continues to increase and reaches a maximum value. As for the magnetic pole 47B group, the current decreases in the R phase after reaching the maximum value, the current in the S phase continues to increase, and the current in the T phase continues to decrease. As a result, the magnetic pole 47A of the plate 45B becomes an N pole, and the magnetic pole 47B of the plate 45B becomes an S pole.

  At this time, the polarities of the magnetic pole 47B of the plate 45A located immediately in front of the magnetic pole 28E and the magnetic pole 28D as the S pole of the magnetic gear 28 are the S pole and the N pole, respectively. Further, the magnetic pole 47A of the plate 45C heading backward as viewed from the magnetic pole 28A which is the N pole of the magnetic gear 28 is the S pole, and the magnetic pole 47A of the plate 45A heading backward as viewed from the magnetic pole 28H which is the S pole of the magnetic gear 28. Is the N pole. As a result, the revolving magnetic gear 28 further rotates (between column C9, time 5 in graph 81, and time 2-3 in 82). Thereafter, similarly, the magnetic poles of the magnetic pole 47A group and the magnetic pole 47B group change according to the change of the current shown in the graphs 81 and 82, and the revolving magnetic gear 28 receives the magnetic force of the magnetic pole 47A group and the magnetic pole 47B group. Rotation continues. Thereafter, the rotation of the rotary table 2 is stopped and the power supply to the magnetic poles 47A and 47B is stopped, whereby the revolution of the magnetic gear 28 that does not rotate is completed. The manner in which the magnetic gear 28 described with reference to FIG. 17 rotates is an example, and the rotation speed of the magnetic gear 28 relative to the revolution speed can be adjusted by adjusting the period of the current and the revolution speed. As described above, as shown in FIGS. 15 to 17, the magnetic gear 28 can rotate and revolve independently of each other.

  Next, an example of a film forming process performed by the film forming apparatus 1 will be described. In the example shown below, as described with reference to FIG. 17, the revolution and rotation of the magnetic gear 28 are performed in parallel, whereby the wafer W rotates and revolves to perform the film forming process. In this film forming process, the rotation of the turntable 2 and the rotation of the wafer holder 24 are not synchronized. More specifically, when the turntable 2 rotates once from a state in which the first direction is directed to a predetermined position in the vacuum vessel 11 and is again positioned at the predetermined position, the wafer W is set to the first direction. The wafer W rotates at a rotation speed (rotation speed) that is directed in a different second direction.

  First, the wafer W is placed on each wafer holder 24 by a transfer mechanism (not shown) (FIG. 18). Hereinafter, description will be made with reference to FIGS. 18 to 21 schematically showing the wafer W placed on the turntable 2. 18 to 21, the respective wafers W are shown as W1 to W5 for convenience of illustration. Further, in order to indicate the direction of the wafer W that is displaced during the film forming process, the arrows directed to the center of the turntable 2 in the region that matches the diameter of the turntable 2 with respect to the diameters of the wafers W1 to W5 before the film forming process. A1 to A5 are attached.

  After placing the wafers W1 to W5, the gate valve 38 is closed, and the vacuum chamber 11 is evacuated to a predetermined pressure by exhausting from the exhaust ports 35 and 36, and the separation gas nozzles 62 and 65 supply N2 gas from the rotary table. 2 is supplied. Further, N 2 gas is supplied as a purge gas from the central region forming part C of the turntable 2 and the gas supply pipe 15 below the turntable 2 and flows from the center side of the turntable 2 to the peripheral side. Further, the temperature of the heater 33 rises, the rotary table 2 and the wafer holder 24 are heated by the radiant heat from the heater 33, and the wafers W <b> 1 to W <b> 5 are heated to a predetermined temperature by the heat transfer from the wafer holder 24.

  Thereafter, the rotation and revolution of the magnetic gear 28 described with reference to FIG. 17, that is, the revolution and rotation of the wafer W placed on the wafer holder 24 are started. For example, simultaneously with the start of these revolutions and rotations, the supply of each gas from the source gas nozzle 61, the oxidizing gas nozzle 63, and the plasma generating gas nozzle 64 and the formation of plasma by applying a high frequency from the high frequency power source 76 to the antenna 75 are started. Is done. FIG. 19 shows a state in which the time has elapsed since the start of film formation, the rotary table 2 has rotated 180 ° from the start of film formation, and the orientation of the wafer W has changed due to the rotation.

  FIG. 22 shows the flow of each gas in the vacuum vessel 11 with arrows. Since the separation region D to which the N2 gas is supplied is provided between the adsorption region R1 and the oxidation region R2, the source gas supplied to the adsorption region R1 and the oxidation gas supplied to the oxidation region R2 are the turntable 2 The exhaust gas is exhausted from the exhaust port 35 together with the N2 gas without being mixed with each other. Further, since the separation region D to which N2 gas is supplied is also provided between the adsorption region R1 and the plasma formation region R3, the source gas, the plasma generating gas and the plasma formation region to be supplied to the plasma formation region R3 are provided. The oxidizing gas from the upstream side in the rotation direction of R3 toward the separation region D is exhausted from the exhaust port 36 together with the N2 gas without being mixed with each other on the rotary table 2. The N 2 gas supplied from the central region forming part C and the gas supply pipe 15 is also removed from the exhaust ports 35 and 36.

With the supply and exhaust of each gas as described above, the wafers W1 to W5 rotate while rotating while the adsorption region R1 below the nozzle cover 57 of the source gas nozzle 61 and the oxidation region R2 below the oxidation gas nozzle 63. The plasma forming region R3 below the plasma forming unit 61 is repeatedly moved in order. In the adsorption region R1, the BTBAS gas discharged from the raw material gas nozzle 61 is adsorbed by the wafer W, and in the oxidation region R2, the adsorbed BTBAS gas is oxidized by the O ₃ gas supplied from the oxidizing gas nozzle 63 to form silicon oxide molecules. One or more layers are formed. In the plasma formation region R3, the molecular layer of silicon oxide is exposed to plasma and modified.

  As described above, the wafer holder 24 rotates without being synchronized with the rotation of the turntable 2, and each wafer W1 to W5 is directed in a different direction each time it is located at a predetermined position in the suction region R1. FIG. 20 shows a state in which the turntable 2 has made one rotation since the start of the film forming process. FIG. 21 shows a state in which the rotation of the turntable 2 is further continued from the state shown in FIG. 9 and the direction of the wafers W1 to W5 is directed to a direction rotated 180 ° from the direction at the start of the film forming process. Show. As the orientation of the wafers W1 to W5 changes in this way, each part in the circumferential direction of the wafer W passes through different positions in the suction region R1. Therefore, even if the concentration distribution of the source gas varies at each position in the adsorption region R1, the amount of the source gas adsorbed on the wafer W from the start of the film formation process to the end of the film formation process is determined. Can be aligned at each part in the direction. As a result, it is possible to suppress the uneven thickness of the SiO 2 film formed on the wafer W at each portion in the circumferential direction of the wafer W.

  In this way, the rotation of the turntable 2 is continued and the silicon oxide molecular layers are sequentially stacked to form the silicon oxide film and the film thickness gradually increases. Then, when the film forming process is performed so as to obtain the set target film thickness, the rotation of the turntable 2 and the rotation of the wafer holder 24 are stopped, and the film forming process ends. For example, at the end of the film forming process, the wafers W1 to W5 are located at the same position as when the film forming process is started, and the directions of the wafers W1 to W5 are directed to the same direction as when the film forming process is started. Therefore, the wafers W1 to W5 are placed at the positions and orientations shown in FIG. 18, and each of them rotates an integer number of times from the start to the end of the film forming process. At the end of the film forming process, the supply of each gas from the gas nozzle 61 to the gas nozzle 65 and the formation of plasma are also stopped. Thereafter, the wafers W1 to W5 are unloaded from the vacuum container 11 by the transfer mechanism.

  In the film forming apparatus 1, by rotating the turntable 2, the processing gas is supplied to the wafer W while the wafer W placed on the wafer holder 24 on the surface of the turntable 2 is revolved and processed. In doing so, a magnetic gear 28 constituted by a plurality of magnetic poles rotating together with the wafer holder 24, and a group of plates 45 constituting the magnetic poles 48A and 48B for rotation of the magnetic gear 28 along the circumferential direction of the rotary table 2; Is provided. A current is supplied to the coils 48A and 48B of the plate 45 so that the magnetic gear 28 rotates by the magnetic force between the magnetic pole of the magnetic gear 28 and the magnetic poles 48A and 48B of the plate 45. Therefore, since the wafer W can be rotated independently of the rotation of the turntable 2, the film thickness uniformity in the circumferential direction of the wafer W can be improved. Therefore, the uniformity of the film thickness can be increased over the entire wafer W, and as described in the background art section, the film thickness in the circumferential direction can be increased after the concentric film thickness distribution is formed on the wafer W. Uniformity can also be increased.

  By the way, the film forming process is not limited to the one shown in FIGS. For example, in the state where each gas is supplied into the vacuum vessel 11 as described with reference to FIG. 22, film formation is performed by rotating the turntable 2 m so that the magnetic gear 28 does not rotate as described with reference to FIG. Step S1). m is an arbitrary number. Thereafter, for example, the supply of the source gas, the supply of the oxidizing gas, and the plasma formation are once stopped, and the direction of the wafer W is changed by, for example, 90 ° with the rotation of the turntable 2 stopped as described with reference to FIG. In this manner, the wafer W is rotated (step S2).

  Thereafter, the supply of the source gas, the supply of the oxidizing gas, and the formation of the plasma are restarted, and the film is formed by rotating the turntable 2 m so that the magnetic gear 28 does not rotate. That is, step S1 is performed again. In this way, steps S1 and S2 are repeated four times. After steps S1 and S2 are repeated four times, steps S1 and S2 may be further repeated four times. Even when such a film forming process is performed, a film having a highly uniform film thickness can be formed in the circumferential direction of the wafer W by changing the orientation of the wafer W when passing through the regions R1 to R3. it can.

  As shown in an evaluation test described later, the angle at which the orientation of the wafer W is changed in step S2 is not limited to 90 °, and processing with higher uniformity can be performed on the entire surface of the wafer W as the angle decreases. However, in order to perform processing with high uniformity in the circumferential direction of the wafer W, film forming processing is performed in which the rotary table 2 in step S1 is rotated by m by a multiple of (360 ° / angle for changing the direction of the wafer W). That is, in the case of changing the 90 ° direction, 360 ° / 90 ° = 4, so step S1 is performed 4 × A (A is an integer) times.

  As described above, since the film forming apparatus 1 can independently perform the revolution and rotation of the wafer W, the rotation of the wafer W is improved so as to improve the film quality according to the type and film thickness of the film to be formed. There is an advantage that the speed and the revolution speed can be easily adjusted. Further, when the wafer W is transferred between the transfer mechanism and the wafer holder 24, the lifting pins need to pass through the through holes provided in the wafer holder 24, but the wafer holder 24 does not have to revolve the rotary table 2. By rotating, the positioning can be easily performed.

  By the way, in the film forming apparatus 1 described above, a three-phase alternating current is supplied to the plate 45 as an n-phase alternating current (n is an integer), but the n-phase alternating current may be a two-phase alternating current or a five-phase alternating current. It may be. Further, a magnet may be provided on the side surface of the rotating shaft 26 that is a rotating body to form a magnetic gear, and the magnetic pole 45 </ b> A group and the magnetic pole 45 </ b> B group may be arranged to face the side surface of the rotating shaft 26. That is, the positional relationship between the magnetic gear and the magnetic pole 45A group and the magnetic pole 45B group is not limited to the examples shown in FIGS. Further, in the above example, a wafer holder 24 which is a mounting table is provided on the turntable 2. Here, “the mounting table is provided on the rotary table” is not limited to the case where the mounting table is directly provided, and there is a support portion that supports the rotary table, and the mounting table is provided on the support portion, that is, The case where it is indirectly provided on the rotary table is also included.

  The substrate processing apparatus of the present invention can be applied to an apparatus that performs gas processing on the wafer W placed on the turntable 2. Therefore, the present invention is not limited to being applied to a film forming apparatus that performs ALD, and may be applied to a film forming apparatus that performs CVD. Further, the present invention is not limited to being applied to a film forming apparatus. For example, the present invention is configured as a reforming apparatus in which the source gas and the oxidizing gas are not supplied from the gas nozzles 61 and 63 in the film forming apparatus 1 and only the surface modification process of the wafer W is performed by the plasma forming unit 71. May be.

  By the way, as described above, since the film forming apparatus 1 can independently rotate and revolve the wafer W, the rotation speed of the rotation of the wafer W can be set to be relatively low. This setting has an advantage that the wafer W can be prevented from jumping out of the turntable 2 due to the centrifugal force of rotation of the wafer W. Further, when the wafer W is revolved at a relatively high speed, the rotation of the wafer W is stopped as described above, and the operation of changing the orientation of the wafer W when the revolution is stopped is performed. Therefore, it is possible to prevent the wafer W from jumping out of the turntable 2 from the point that this operation is possible. Furthermore, even if the orientation at the start of rotation of the wafer W deviates from a preset orientation for some reason, it can be corrected without revolving the wafer W. Therefore, there is no need to open the vacuum vessel 11 in order to correct this orientation, and there is an advantage that the correction is easy.

  Further, in the film forming apparatus 1, the torque applied to the five magnetic gears 28 provided in the circumferential direction of the turntable 2 can be controlled by the voltage applied to the plate 45, which is an electromagnet, and each magnetic gear 28 can be rotated simultaneously. . By rotating the magnetic gear 28 at the same time as described above, it is possible to prevent a large force from being applied in one direction on the rotary table 2, so that the rotary table 2 can be smoothly rotated. In the description with reference to each of the above drawings, it has been described that the rotation of the magnetic gear 28 is controlled by the current. However, the voltage supplied to the plate 45 is also controlled in the same manner as the current. It can be said that the 28 rotations are controlled.

  Further, since the magnetic gear 28 made of a permanent magnet is pulled by the magnetic force from the center side and the peripheral side of the turntable 2 during rotation, the rotation shaft 26 can be prevented from being inclined. Accordingly, the rotation shaft 26 can be prevented from coming into contact with other members during the revolution of the wafer W, so that it is not necessary to increase the distance between the rotation shaft 26 and the surrounding members, and the degree of freedom in designing the apparatus is increased. There are advantages.

  For the film forming apparatus 1, a plurality of, for example, five areas divided in the circumferential direction are set. Then, the plate 45 group may be configured to be supplied with current independently for each area, and the rotation speed of the revolving-moving wafer W may be controlled for each area. By doing so, for example, the first rotation speeds different from each other while the wafer W passes through the first area, the second area, the third area, the fourth area, and the fifth area due to revolution, for example. The second rotation speed, the third rotation speed, the fourth rotation speed, and the fifth rotation speed can be used. Any one of the first to fifth rotation speeds may be 0, that is, the rotation may be stopped only in a predetermined area during the revolution. The source gas adsorption region R1, the oxidation region R2, and the plasma formation region R3 may belong to different areas, and the wafer W may rotate at different speeds during the source gas adsorption, oxidation, and plasma modification. . Further, when the voltages are individually supplied for each area as described above, the five magnetic gears 28 can be rotated in parallel with each other to correct the direction of each magnetic gear 28 described above.

(Evaluation test)
An evaluation test related to the present invention will be described. In the description of each evaluation test, for the wafer W placed on the wafer holder 24, the diameter of the wafer W that coincides with the diameter of the turntable 2 at the start of the film forming process is described as a Y line. Therefore, the Y line is a region indicated by arrows A1 to A5 in FIG. And the diameter of the wafer W orthogonal to this Y line is described as X line.

Evaluation test 1
A test was conducted to examine the change in film thickness distribution due to rotation of the wafer W having a diameter of 300 mm. As the evaluation test 1-1, a simulation for forming a film without rotating the wafer W in the film forming apparatus 1 was performed. In addition, as evaluation test 1-2, a simulation was performed in which film formation was performed under the same conditions as in evaluation test 1-1 except that the wafer W was rotated. However, in this evaluation test 1-2, unlike the embodiment, the wafer W is set to rotate by 180 ° from the start of the film formation process to the end of the film formation process. Further, a test similar to the evaluation test 1-2 was performed as the evaluation test 1-3, but the wafer W was set to rotate by 45 ° as a difference. Further, as an evaluation test 1-4, a simulation was performed under the same conditions as the evaluation tests 1-1 to 1-3 except that the wafer W was set to rotate an integer number of times as in the embodiment. In each of the evaluation tests 1-1 to 1-4, the film thickness distribution in the plane of the wafer W was measured.

  23 schematically shows in-plane film thickness distributions of the wafers W of the evaluation tests 1-1 and 1-2, respectively, and the upper and lower parts of FIG. 23 show the evaluation tests 1-3 and 1-4, respectively. 2 schematically shows the in-plane film thickness distribution of the wafer W. The actually obtained test results are computer graphics in which a color corresponding to the film thickness is added to the surface of the wafer W. In FIG. 23 and FIG. Each of the regions in which is a predetermined range is surrounded by contour lines and shown with a pattern.

  Moreover, the upper part of FIG. 25 is a graph showing the film thickness distribution of each Y line of the evaluation tests 1-1 and 1-4, and the lower part is a film thickness distribution of each X line of the evaluation tests 1-1 and 1-4. It is a graph which shows. The horizontal axis of each graph indicates the distance (unit: mm) from one end of the wafer W. One end of the wafer W in the Y-line graph is the end on the central axis side of the turntable 2. The vertical axis of each graph represents the film thickness (unit: nm). The upper part of FIG. 26 is a graph showing the film thickness distribution of each Y line in evaluation tests 1-2 and 1-3, and the lower part is the film thickness distribution of each X line in evaluation tests 1-2 and 1-3. It is a graph to show.

  23 and FIG. 24, the uniformity of the film thickness distribution in the circumferential direction of the wafer W is increased by rotating the wafer W, and in the evaluation test 1-4 rotated by an integer number of times, the circumferential direction of the wafer W is rotated. It can be seen that the uniformity of is extremely high. Moreover, when it sees about each graph, the big difference is not seen by the film thickness distribution of X line by the evaluation tests 1-1 to 1-4. Regarding the film thickness distribution of the Y line, a slight difference in film thickness between one end and the other end of the Y line seen in the evaluation test 1-1 is small in the evaluation tests 1-2 and 1-3. It is almost lost in Evaluation Test 1-4. Therefore, it can be seen from each graph that the film thickness distribution in the circumferential direction of the wafer W is highly uniform.

  Further, for each of the evaluation tests 1-1 to 1-4, it was calculated from the film thickness measured at 49 positions in the plane of the wafer W including the measurement positions on the X line and the Y line. Table 1 below shows the average value of the film thickness, the maximum value of the film thickness, the minimum value of the film thickness, the difference between the maximum value and the minimum value of the film thickness, and WinW which is an index representing the in-plane uniformity. WinW is ± {(maximum value of film thickness−minimum value of film thickness) / (average value of film thickness)} / 2 × 100 (%), and Table 1 shows the absolute value. The smaller the absolute value, the higher the in-plane uniformity. Hereinafter, when simply referred to as WinW, it is assumed to be an absolute value of a calculated value from the above formula. By comparing the WinW of the evaluation tests 1-1 to 1-4 and rotating the wafer W, the uniformity of the film thickness is increased not only in the circumferential direction but also in the entire surface of the wafer W, and the evaluation It can be seen that Test 1-4 has the highest uniformity of film thickness across the entire surface. Therefore, from this evaluation test 1, it is understood that rotating the wafer W as described in the embodiment is effective for increasing the uniformity of the film thickness in the surface of the wafer W, and the number of rotations. It can be seen that it is particularly effective to use an integer.

Evaluation test 2
In the above-described film forming apparatus 1, by setting the Ar gas and the NH3 gas to be discharged from the gas nozzle 64 of the plasma forming unit 71, the film was set to be nitrided in the plasma forming region R3. Then, in order to obtain a nitride film having a predetermined film thickness in the film forming apparatus 1, a simulation was performed for each of the cases where the wafer W was rotated and the case where the wafer W was not rotated, and the above WinW was obtained. In this nitriding process, the temperature of the wafer W is set to 400 ° C., the pressure in the vacuum vessel 11 is set to 1.8 Torr, the power supplied to the antenna 75 is 3.3 kW, the flow rate of NH 3 gas is set to 100 sccm, and the flow rate of Ar gas is set to 10,000 sccm. did. The speed when the wafer W rotates was set to 10 rpm.

  The graph of FIG. 27 shows the result of the evaluation test 2. The horizontal axis of the graph indicates the processing time required to obtain the film thickness set for the nitride film, and the vertical axis of the graph indicates the set film thickness of the nitride film and the absolute value of WinW. As shown in the graph, when the wafer W is rotated, WinW is lower than when the wafer W is not rotated. From the graph, when the processing time is 1 minute, 3 minutes, and 5 minutes, WinW when the wafer W rotates is about 1/3 that when the wafer W does not rotate. When the processing time is 10 minutes, WinW when the wafer W rotates is about 1/10 that when the wafer W does not rotate. Thus, it was confirmed from the evaluation test 2 that the uniformity of the in-plane processing of the wafer W can be improved by rotating the wafer W when performing the plasma processing. Therefore, it can be seen that the configuration of the film forming apparatus 1 is effective.

Evaluation test 3
In the film forming apparatus 1, a gas containing Ti (titanium) as a source gas is supplied from the nozzle 61, and a simulation is performed so that TiO 2 (titanium oxide) is formed on the wafer W instead of SiO 2. And as the evaluation test 3-1, the film-forming process was performed without rotating the wafer W. As shown in FIG. As evaluation test 3-2, after the wafer W was revolved and the film formation process was performed, the wafer W was rotated so that the direction changed 180 °, and then the wafer W was revolved and the film formation process was performed. . As the evaluation test 3-3, after the wafer W was revolved and a film forming process was performed, the wafer W was rotated so that the direction changed by 90 °. The film formation by this revolution and the change of the 90 ° direction were performed four times. In the evaluation test 3-4, after the wafer W was revolved and the film formation process was performed, the wafer W was rotated so that the direction changed by 60 °. The film formation by this revolution and the change of the direction of 60 ° were performed 6 times. For each of the evaluation tests 3-1 to 3-4, the number of revolutions of the rotary table 2 is equal. That is, in the evaluation tests 3-2, 3-3, and 3-4, the film forming process is divided into two times, four times, and six times. For the wafers W of these evaluation tests 3-1 to 3-4, the above WinW and 3σ (unit:%) of the in-plane film thickness were obtained.

  The graph of FIG. 28 shows the result of the evaluation test 3. The horizontal axis of the graph indicates the number of times the film forming process is divided. The number of divisions for evaluation test 3-1 is 1. The vertical axis of the graph indicates the acquired WinW and 3σ. WinW and 3σ are smaller in evaluation tests 3-2 to 3-4 than in evaluation test 3-1. That is, it can be seen that the in-plane uniformity of the film thickness is high. Accordingly, it is not necessary to rotate the wafer W in parallel with the revolution of the wafer W. The timing of performing the revolution and rotation of the wafer W is shifted, and even if the revolution and rotation are repeated, the wafer W is not rotated. It can be seen that processing with high uniformity can be performed.

W Wafer 1 Film forming apparatus 11 Vacuum container 2 Rotary table 24 Wafer holder 26 Rotating shaft 27 Magnetic gear 45 Plate 47A, 47B Magnetic pole 51A, 51B Power supply unit 61 Raw material gas nozzle 63 Oxidizing gas nozzle 71 Plasma forming section

Claims (7)

In a substrate processing apparatus that places a substrate on one side of a rotary table provided in a processing container and supplies the processing gas to the substrate while rotating the rotary table while rotating the substrate, and processing the substrate,
A rotation table provided on the rotary table so as to be rotatable, and a mounting table for mounting the substrate;
A rotating body provided below the mounting table and rotating together with the mounting table;
A plurality of magnetic poles arranged along the circumferential direction of the rotating body;
An electromagnet group that is provided independently of the rotary table and forms a magnetic pole group for driving a rotating body in which a plurality of magnetic poles are arranged along the circumferential direction of the rotary table;
A power supply unit for supplying a current to the coil of the electromagnet so that the rotating body rotates by a magnetic force between the magnetic pole arranged on the rotating body and each magnetic pole of the magnetic pole group for driving the rotating body; A substrate processing apparatus comprising the substrate processing apparatus. The magnetic pole group is configured by arranging a plurality of sets of n (n is an integer of 2 or more) magnetic poles arranged continuously along the circumferential direction of the rotary table,
2. The substrate processing apparatus according to claim 1, wherein an n-phase alternating current is supplied to the coils of the electromagnets that respectively form the n magnetic poles forming the set.   The substrate processing apparatus according to claim 2, wherein the n-phase alternating current is a three-phase alternating current.   The magnetic pole group includes an inner magnetic pole group located on the rotation center side of the rotary table with respect to the orbit of the center of the rotation axis as viewed in a plane, and an outer magnetic pole group located on the opposite side of the rotation center. The substrate processing apparatus according to claim 1, further comprising a substrate processing apparatus.   An inner power source for supplying current to the electromagnet coil constituting the magnetic pole group in the inner magnetic pole group, and an inner power source for supplying current to the electromagnet coil constituting the magnetic pole group in the outer magnetic pole group The substrate processing apparatus according to claim 4, further comprising an outer power supply unit that is separate from the unit.   6. The substrate processing apparatus according to claim 5, further comprising a phase difference setting unit that sets a phase difference between the inner power source unit and the outer power source unit. In a substrate processing method of placing a substrate on one surface side of a rotary table provided in a processing container and supplying the processing gas to the substrate while processing the substrate by rotating the rotary table,
A step of placing the substrate on a mounting table that is rotatably provided on the rotary table;
Rotating the rotating body provided below the mounting table together with the mounting table;
A plurality of magnetic poles arranged along the circumferential direction of the rotating body, and an electromagnet group that is provided independently of the rotating table and forms a magnetic pole group for driving the rotating body, and the circumference of the rotating table Supplying a current to a coil of the electromagnet by a power supply unit so that the rotating body rotates by a magnetic force between a plurality of magnetic poles arranged along a direction;
A substrate processing method comprising:

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