Patent Publication Number: US-2023139945-A1

Title: Substrate processing apparatus, substrate processing method, method of manufacturing semiconductor device, and non-transitory computer-readable recording medium

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This non-provisional U.S. patent application is a continuation of U.S. patent application Ser. No. 17/692,722 filed on Mar. 11, 2022 and claims priority under 35 U.S.C. § 119 of Japanese Patent Application No. 2021-178348, filed on Oct. 29, 2021, in the Japanese Patent Office, the entire contents of which are hereby incorporated by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a substrate processing apparatus. 
     BACKGROUND 
     According to some related arts, a substrate processing apparatus capable of performing a substrate processing by exciting a process gas into a plasma state by supplying an electric power to two coils may be used. 
     For example, in the substrate processing apparatus described above, the two coils of the same diameter are arranged coaxially. Therefore, a plasma density may be biased in a direction parallel to a surface of the substrate, and a uniformity of the substrate processing on the surface of the substrate may decrease. 
     SUMMARY 
     According to the present disclosure, there is provided a technique capable of improving a uniformity of a substrate processing on a surface of a substrate. 
     According to one aspect of the technique of the present disclosure, there is provided a substrate processing apparatus including: a process chamber including: a plasma generation space capable of generating a plasma; and a substrate processing space capable of processing a substrate; a gas supplier capable of supplying a gas into the plasma generation space; a first coil provided to surround the plasma generation space and configured to generate a first voltage distribution; and a second coil provided to surround the plasma generation space and configured to generate a second voltage distribution such that a peak of the second voltage distribution does not overlap with a peak of the first voltage distribution. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a diagram schematically illustrating a configuration of a substrate processing apparatus preferably used in one or more embodiments of the present disclosure. 
         FIG.  2    is a diagram schematically illustrating a first resonance coil used in a comparative example of the present disclosure. 
         FIG.  3    is a diagram schematically illustrating a relationship between a current and a voltage in the first resonance coil shown in  FIG.  2   . 
         FIG.  4    is a diagram schematically illustrating an internal state of a process furnace when a process gas is excited into a plasma state using the first resonance coil shown in  FIG.  2   . 
         FIG.  5    is a diagram schematically illustrating a horizontal cross-section of the process furnace at a central portion of the first resonance coil shown in  FIG.  4    in an axial direction. 
         FIG.  6    is a diagram schematically illustrating a second resonance coil preferably used in the embodiments of the present disclosure. 
         FIG.  7    is a diagram schematically illustrating a relationship between the current and the voltage in the first resonance coil and the second resonance coil. 
         FIG.  8    is a diagram schematically illustrating an internal state of the process furnace when the process gas is excited into the plasma state using the first resonance coil and the second resonance coil shown in  FIG.  7   . 
         FIG.  9    is a diagram schematically illustrating a horizontal cross-section of the process furnace at central portions of the first resonance coil and the second resonance coil shown in  FIG.  8    in the axial direction. 
         FIG.  10    is a block diagram schematically illustrating a configuration of a controller (which is a control structure) and related components of the substrate processing apparatus preferably used in the embodiments of the present disclosure. 
         FIG.  11    is a flow chart schematically illustrating a substrate processing preferably used in the embodiments of the present disclosure. 
         FIG.  12    is a diagram schematically illustrating an internal state of the process furnace when the process gas is excited into the plasma state using a modified example of a resonance coil preferably used in the embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments 
     Hereinafter, one or more embodiments (also simply referred to as “embodiments”) according to the technique of the present disclosure will be described with reference to the drawings. The drawings used in the following descriptions are all schematic. For example, a relationship between dimensions of each component and a ratio of each component shown in the drawing may not always match the actual ones. Further, even between the drawings, the relationship between the dimensions of each component and the ratio of each component may not always match. 
     (1) Configuration of Substrate Processing Apparatus 
     Hereinafter, a substrate processing apparatus  100  according to the embodiments of the present disclosure will be described with reference to  FIGS.  1  through  10   . For example, the substrate processing apparatus  100  according to the present embodiments is configured to mainly perform a substrate processing such as an oxidation process onto a film formed on a surface of a substrate or onto a base of the substrate. 
     Process Chamber 
     The substrate processing apparatus  100  includes a process furnace  202  in which a wafer  200  serving as the substrate is processed by a plasma. The process furnace  202  includes a process vessel  203 , and a process chamber  201  is defined by the process vessel  203 . The process vessel  203  includes a dome-shaped upper vessel  210  serving as a first vessel and a bowl-shaped lower vessel  211  serving as a second vessel. By covering the lower vessel  211  with the upper vessel  210 , the process chamber  201  is defined. The upper vessel  210  constitutes a plasma vessel in which a plasma generation space  201 A is provided. In the plasma generation space  201 A, a process gas is excited into a plasma state. 
     In addition, a gate valve  244  is provided on a lower side wall of the lower vessel  211 . While the gate valve  244  is open, the wafer  200  can be transferred (loaded) into the process chamber  201  through a substrate loading/unloading port  245  using a substrate transfer device (not shown) or be transferred (unloaded) out of the process chamber  201  through the substrate loading/unloading port  245  using the substrate transfer device. While the gate valve  244  is closed, the gate valve  244  maintains the process chamber  201  airtight. 
     The process chamber  201  includes the plasma generation space  201 A and a substrate processing space  201 B. The plasma generation space  201 A is a space in which a first resonance coil  212  and a second resonance coil  214 , which are coils serving as electrodes, are provided around the space, and the plasma is generated in the plasma generation space  201 A. More specifically, the plasma generation space  201 A refers to a space in the process chamber  201  above a lower end of the first resonance coil  212  and below an upper end of the first resonance coil  212 . The substrate processing space  201 B is a space that communicates with the plasma generation space  201 A and in which the wafer  200  is processed. More specifically, the substrate processing space  201 B refers to a space in which the wafer  200  is processed by using the plasma, for example, a space below the lower end of the first resonance coil  212 . According to the present embodiments, a diameter of the plasma generation space  201 A in a horizontal direction is the same as a diameter of the substrate processing space  201 B in the horizontal direction. A configuration constituting the plasma generation space  201 A may also be referred to as a “plasma generation room”, and a configuration constituting the substrate processing space  201 B may also be referred to as a “substrate processing room”. Further, the plasma generation space  201 A may also be referred to as a “plasma generation region” in the process chamber  201 , and the substrate processing space  201 B may also be referred to as a “substrate processing region” in the process chamber  201 . 
     Susceptor 
     A susceptor (which is a substrate mounting table)  217  serving as a substrate support on which the wafer  200  is placed is provided at a center of a bottom portion of the process chamber  201 . The susceptor  217  is provided in the process chamber  201  and below the first resonance coil  212 . 
     A heater  217 B serving as a heating structure is integrally embedded in the susceptor  217 . When an electric power is supplied to the heater  217 B, the heater  217 B is configured to heat the wafer  200 . 
     The susceptor  217  is electrically insulated from the lower vessel  211 . An impedance adjusting electrode  217 C is provided in the susceptor  217  in order to further improve a uniformity of a density of the plasma generated on the wafer  200  placed on the susceptor  217 . The impedance adjustment electrode  217 C is grounded via a variable impedance regulator  275  serving as an impedance adjusting structure. 
     A susceptor elevator  268  including a driving structure capable of elevating and lowering the susceptor  217  is provided at the susceptor  217 . Through-holes  217 A are provided at the susceptor  217 , and wafer lift pins  266  are provided on a bottom surface of the lower vessel  211 . When the susceptor  217  is lowered by the susceptor elevator  268 , the wafer lift pins  266  are configured to penetrate the through-holes  217 A without contacting the susceptor  217 . 
     Gas Supplier 
     A gas supply head  236  is provided above the process chamber  201 , that is, on an upper portion of the upper vessel  210 . The gas supply head  236  includes a cap-shaped lid  233 , a gas inlet port  234 , a buffer chamber  237 , an opening  238 , a shield plate  240  and a gas outlet port  239 . The gas supply head  236  is configured such that a gas such as a reactive gas is supplied into the process chamber  201  through the gas supply head  236 . The buffer chamber  237  functions as a dispersion space in which the gas such as the reactive gas introduced (supplied) through the gas inlet port  234  is dispersed. 
     A downstream end of an oxygen-containing gas supply pipe  232 A through which an oxygen-containing gas is supplied, a downstream end of a hydrogen-containing gas supply pipe  232 B through which a hydrogen-containing gas is supplied and a downstream end of an inert gas supply pipe  232 C through which an inert gas is supplied are connected to the gas inlet port  234  through a confluence pipe  232 . Hereinafter, the oxygen-containing gas supply pipe  232 A may also be simply referred to as a “gas supply pipe  232 A”, the hydrogen-containing gas supply pipe  232 B may also be simply referred to as a “gas supply pipe  232 B”, and the inert gas supply pipe  232 C may also be simply referred to as a “gas supply pipe  232 C”. An oxygen-containing gas supply source  250 A, a mass flow controller (MFC)  252 A serving as a flow rate controller and a valve  253 A serving as an opening/closing valve are sequentially provided at the oxygen-containing gas supply pipe  232 A in this order from an upstream side to a downstream side of the oxygen-containing gas supply pipe  232 A in a gas flow direction. A hydrogen-containing gas supply source  250 B, an MFC  252 B and a valve  253 B are sequentially provided at the hydrogen-containing gas supply pipe  232 B in this order from an upstream side to a downstream side of the hydrogen-containing gas supply pipe  232 B in the gas flow direction. An inert gas supply source  250 C, an MFC  252 C and a valve  253 C are sequentially provided at the inert gas supply pipe  232 C in this order from an upstream side to a downstream side of the inert gas supply pipe  232 C in the gas flow direction. A valve  243 A is provided on a downstream side of the confluence pipe  232  where the oxygen-containing gas supply pipe  232 A, the hydrogen-containing gas supply pipe  232 B and the inert gas supply pipe  232 C join. The confluence pipe  232  is connected to an upstream end the gas inlet port  234 . It is possible to supply the process gas such as the oxygen-containing gas, the hydrogen-containing gas and the inert gas into the process chamber  201  via the oxygen-containing gas supply pipe  232 A, the hydrogen-containing gas supply pipe  232 B and the inert gas supply pipe  232 C by opening and closing the valves  253 A,  253 B,  253 C and  243 A while adjusting flow rates of the respective gases by the MFCs  252 A,  252 B and  252 C. 
     For example, an oxygen-containing gas supplier (which is an oxygen-containing gas supply structure or an oxygen-containing gas supply system) according to the present embodiments is constituted mainly by the oxygen-containing gas supply pipe  232 A, the MFC  252 A, the valve  253 A and the valve  243 A. In addition, a hydrogen-containing gas supplier (which is a hydrogen-containing gas supply structure or a hydrogen-containing gas supply system) according to the present embodiments is constituted mainly by the hydrogen-containing gas supply pipe  232 B, the MFC  252 B, the valve  253 B and the valve  243 A. In addition, an inert gas supplier (which is an inert gas supply structure or an inert gas supply system) according to the present embodiments is constituted mainly by the inert gas supply pipe  232 C, the MFC  252 C, the valve  253 C and the valve  243 A. 
     A gas supplier (which is a gas supply structure or a gas supply system) according to the present embodiments is constituted mainly by the oxygen-containing gas supply pipe  232 A, the hydrogen-containing gas supply pipe  232 B, the inert gas supply pipe  232 C, the MFCs  252 A,  252 B and  252 C, the valves  253 A,  253 B and  253 C and the valve  243 A. The gas supplier (gas supply system) is configured such that the process gas can be supplied into the process vessel  203 . For example, one of the oxygen-containing gas supplier, the hydrogen-containing gas supplier and the inert gas supplier or a combination thereof may also be referred to as the “gas supplier”. 
     Exhauster 
     A gas exhaust port  235  is provided on a side wall of the lower vessel  211 . An inner atmosphere of the process chamber  201  (for example, the reactive gas in the process chamber  201 ) is exhausted through the gas exhaust port  235 . An upstream end of a gas exhaust pipe  231  is connected to the gas exhaust port  235 . An APC (Automatic Pressure Controller) valve  242  serving as a pressure regulator (pressure adjusting structure), a valve  243 B serving as an opening/closing valve and a vacuum pump  246  serving as a vacuum exhaust apparatus are sequentially provided at the gas exhaust pipe  231  in this order from an upstream side to a downstream side of the gas exhaust pipe  231  in the gas flow direction. An exhauster (which is an exhaust structure or an exhaust system) according to the present embodiments is constituted mainly by the gas exhaust port  235 , the gas exhaust pipe  231 , the APC valve  242  and the valve  243 B. The exhauster may further include the vacuum pump  246 . 
     Plasma Generator 
     The first resonance coil  212  and the second resonance coil  214  are respectively arranged on an outer side of the process vessel  203  so as to surround an outer periphery of the process vessel  203 . Specifically, the first resonance coil  212  and the second resonance coil  214  are respectively arranged so as to surround an outer periphery of a portion (region) corresponding to the plasma generation space  201 A (that is, an outer periphery of the plasma generation room) in the process vessel  203 . The first resonance coil  212  is provided by winding a conductor  212 A of a line shape or a string shape a plurality of times in a spiral shape in the same direction. Both ends (that is, an upper end  212 B and a lower end  212 C shown in  FIG.  8   ) of the first resonance coil  212  are grounded, and a portion of the first resonance coil  212  between the upper end  212 B and the lower end  212 C surrounds the outer periphery of the process vessel  203 . Specifically, the first resonance coil  212  surrounds an outer peripheral portion of the process chamber  201 , that is, an outer periphery of a side wall of the upper vessel  210 . In other words, the process vessel  203  is inserted into an inner side of the first resonance coil  212 . In addition, according to the present embodiments, the first resonance coil  212  and the outer periphery (outer surface) of the process vessel  203  are provided close to each other such that a high frequency electromagnetic field generated by the first resonance coil  212  can excite the process gas in the process vessel  203  into the plasma state by the plasma. Further, a winding diameter of the first resonance coil  212  according to the present embodiments is constant and the same at positions on the first resonance coil  212 . An RF power is supplied to the first resonance coil  212 . 
     The second resonance coil  214  is provided by winding a conductor  214 A of a line shape or a string shape a plurality of times in a spiral shape in the same direction. Both ends (that is, an upper end  214 B and a lower end  214 C shown in  FIG.  8   ) of the second resonance coil  214  are grounded, and a portion of the second resonance coil  214  between the upper end  214 B and the lower end  214 C surrounds the outer periphery of the process vessel  203 . Specifically, the second resonance coil  214  surrounds the outer peripheral portion of the process chamber  201 , that is, the outer periphery of the side wall of the upper vessel  210 . In other words, the process vessel  203  is inserted into an inner side of the second resonance coil  214 . In addition, according to the present embodiments, similar to the first resonance coil  212 , the second resonance coil  214  and the outer periphery (outer surface) of the process vessel  203  are provided close to each other such that a high frequency electromagnetic field generated by the second resonance coil  214  can excite the process gas in the process vessel  203  into the plasma state by the plasma. Further, a winding diameter of the second resonance coil  214  according to the present embodiments is constant and the same at positions on the second resonance coil  214 . Further, according to the present embodiments, the winding diameter D 1  of the first resonance coil  212  and the winding diameter D 2  of the second resonance coil  214  are different. Specifically, the winding diameter D 2  of the second resonance coil  214  is set to be greater than the winding diameter D 1  of the first resonance coil  212 . According to the present embodiments, for example, the winding diameter D 2  is preferably set within a range from 101% to 125%, preferably from 105% to 120% of the winding diameter D 1 . 
     As shown in  FIG.  8   , an axial direction of the first resonance coil  212  (that is, a direction along a spiral axis of the first resonance coil  212 ) and an axial direction of the second resonance coil  214  (that is, a direction along a spiral axis of the second resonance coil  214 ) are the same direction. That is, the axial direction of the second resonance coil  214  is equal to the axial direction of the first resonance coil  212 . More specifically, according to the present embodiments, the spiral axis of the first resonance coil  212  and the spiral axis of the second resonance coil  214  are coaxial. In addition, according to the present embodiments, the axial direction of each resonance coil is the same direction as an up-and-down direction of the substrate processing apparatus  100 , that is, the same direction as a vertical direction. In  FIG.  7   , an upper direction of the substrate processing apparatus  100  is indicated by an arrow “U”, and a radial direction of the process vessel  203  is indicated by an arrow “R”. According to the present embodiments, the radial direction of the process vessel  203  is the same direction as a horizontal direction of the substrate processing apparatus  100 , and is also the same direction as a direction perpendicular to the spiral axis of each resonance coil. Further, the conductor  212 A constituting the first resonance coil  212  and the conductor  214 A constituting the second resonance coil  214  are alternately arranged in the vertical direction (that is, the axial direction of each resonance coil). According to the present embodiments, for example, when the first resonance coil  212  and the second resonance coil  214  are viewed from the vertical direction, an outer peripheral portion of the first resonance coil  212  overlaps with an inner peripheral portion of the second resonance coil  214 . By providing the first resonance coil  212  and the second resonance coil  214  such that a part of the first resonance coil  212  overlaps with a part of the second resonance coil  214  when viewed from the vertical direction, it is possible to suppress an increase in a size of a vessel (not shown) covering each resonance coil in the radial direction. On the other hand, for example, when the first resonance coil  212  and the second resonance coil  214  do not overlap with each other when viewed from the vertical direction, that is, when there is a gap between the first resonance coil  212  and the second resonance coil  214 , by securing a distance between the first resonance coil  212  and the second resonance coil  214 , it is possible to suppress a generation of an arc discharge. Further, the distance between the first resonance coil  212  and the second resonance coil  214  may be set to a distance in advance such that no arc discharge is generated therebetween. In addition, the RF power is supplied to the second resonance coil  214 . 
     As shown in  FIG.  8   , an axial length (that is, a length along the spiral axis) of a coil portion of the first resonance coil  212  is set to be longer than an axial length (that is, a length along the spiral axis) of a coil portion of the second resonance coil  214 . Therefore, the conductor  212 A of the first resonance coil  212  and the conductor  214 A of the second resonance coil  214  are alternately arranged in the vertical direction (that is, the axial direction of each resonance coil) from an upper portion to the vicinity of a central portion of the first resonance coil  212  in the vertical direction. According to the present embodiments, a region in which the first resonance coil  212  and the second resonance coil  214  are arranged is provided on the outer periphery of the process vessel  203 . Specifically, the region in which the first resonance coil  212  and the second resonance coil  214  are arranged may also be referred to as a “first arrangement region”, and is indicated by a reference character “FA” (see  FIG.  8   ). In addition, a region in which the first resonance coil  212  is arranged and the second resonance coil  214  is not arranged may be referred to as a “second arrangement region”, and is indicated by a reference character “SA” (see  FIG.  8   ). The second arrangement region SA is provided closer to the susceptor  217  than the first arrangement region FA in the up-and-down direction of the substrate processing apparatus  100  (that is, the vertical direction). 
     An RF (Radio Frequency) sensor  272 , an RF power supply  273  and a matcher (which is a matching structure)  274  configured to perform an impedance matching or an output frequency matching for the RF power supply  273  are connected to the first resonance coil  212 . 
     The RF power supply  273  is configured to supply the RF power to the first resonance coil  212 . The RF sensor  272  is provided at an output side of the RF power supply  273 . The RF sensor  272  is configured to monitor information of the traveling wave or reflected wave of the RF power supplied from the RF power supply  273 . The information of the reflected wave monitored by the RF sensor  272  is input to the matcher  274 , and the matcher  274  is configured to match (or adjust) an impedance or a frequency of the RF power output from the RF power supply  273  so as to minimize the reflected wave based on the information of the reflected wave input from the RF sensor  272 . 
     The RF power supply  273  includes a power supply controller (which is a control circuit) (not shown) and an amplifier (which is an output circuit) (not shown). The power supply controller includes a high frequency oscillation circuit (not shown) and a preamplifier (not shown) in order to adjust an oscillation frequency and an output. The amplifier amplifies the output to a predetermined output level. The power supply controller controls the amplifier based on output conditions relating to the frequency and the power, which are set in advance through an operation panel (not shown), and the amplifier supplies a constant RF power to the first resonance coil  212  via a transmission line. The RF sensor  272  and the matcher  274  are collectively referred to as a “RF power supplier  271 ” which is a RF power supply structure or a RF power supply system. The RF power supplier  271  may further include the RF power supply  273 . 
     An RF (Radio Frequency) sensor  282 , a RF power supply  283  and a matcher (which is a matching structure)  284  configured to perform an impedance matching or an output frequency matching for the RF power supply  283  are connected to the second resonance coil  214 . 
     The RF power supply  283  is configured to supply the RF power to the second resonance coil  214 . The RF sensor  282  is provided at an output side of the RF power supply  283 . The RF sensor  282  is configured to monitor information of the traveling wave or reflected wave of the RF power supplied from the RF power supply  283 . The information of the reflected wave monitored by the RF sensor  282  is input to the matcher  284 , and the matcher  284  is configured to match (or adjust) an impedance or a frequency of the RF power output from the RF power supply  283  so as to minimize the reflected wave based on the information of the reflected wave input from the RF sensor  282 . 
     The RF power supply  283  includes a power supply controller (which is a control circuit) (not shown) and an amplifier (which is an output circuit) (not shown). The power supply controller includes a high frequency oscillation circuit (not shown) and a preamplifier (not shown) in order to adjust an oscillation frequency and an output. The amplifier amplifies the output to a predetermined output level. The power supply controller controls the amplifier based on output conditions relating to the frequency and the power, which are set in advance through the operation panel (not shown), and the amplifier supplies a constant RF power to the second resonance coil  214  via a transmission line. The RF sensor  282  and the matcher  284  are collectively referred to as a “RF power supplier  281 ” which is a RF power supply structure or an RF power supply system. The RF power supplier  281  may further include the RF power supply  283 . 
     The winding diameter, a winding pitch and the number of winding turns of the first resonance coil  212  are set such that the first resonance coil  212  resonates at a constant wavelength to form a standing wave of a predetermined wavelength. That is, an electrical length of the first resonance coil  212  is set to an integral multiple (n times, where n is equal to or greater than 1) of a wavelength of a predetermined frequency of the RF power supplied from the RF power supply  273 . 
     In addition, the winding diameter, a winding pitch and the number of winding turns of the second resonance coil  214  are set such that the second resonance coil  214  resonates at a constant wavelength to form a standing wave of a predetermined wavelength. That is, an electrical length of the second resonance coil  214  is set to an integral multiple (n times, where n is equal to or greater than 1) of a wavelength of a predetermined frequency of the RF power supplied from the RF power supply  283 . 
     Specifically, considering conditions such as the power to be applied, a strength of a magnetic field to be generated and a shape of the substrate processing apparatus  100  to be applied, the first resonance coil  212  is set such that, for example, the magnetic field of about 0.01 Gauss to about 10 Gauss can be generated by the RF power whose frequency is from 800 kHz to 50 MHz and whose power is from 0.1 kW to 5 kW. For example, the first resonance coil  212  whose effective cross-section is from 50 mm2 to 300 mm2 and whose diameter is from 200 mm to 500 mm is wound, for example, twice to 60 times around an outer circumferential side of the process chamber  201  defining the plasma generation space  201 A. Similarly, considering conditions such as the power to be applied, a strength of a magnetic field to be generated and a shape of the substrate processing apparatus  100  to be applied, the second resonance coil  214  is set such that, for example, the magnetic field of about 0.01 Gauss to about 10 Gauss can be generated by the RF power whose frequency is from 800 kHz to 50 MHz and whose power is from 0.1 kW to 5 kW. For example, the second resonance coil  214  whose effective cross-section is from 50 mm2 to 300 mm2 and whose diameter is from 200 mm to 500 mm is wound, for example, twice to 60 times around the outer circumferential side of the process chamber  201  defining the plasma generation space  201 A. 
     As shown in  FIG.  7   , the first resonance coil  212  and the second resonance coil  214  are arranged such that a position of an anti-node of the standing wave by the first resonance coil  212  and a position of an anti-node of the standing wave by the second resonance coil  214  do not overlap with each other. In other words, a peak of a voltage distribution of the first resonance coil  212  and a peak of a voltage distribution of the second resonance coil  214  do not overlap with each other. Further, the distance between the first resonance coil  212  and the second resonance coil  214  is set to the distance at which no arc discharge is generated between the conductor  212 A of the first resonance coil  212  and the conductor  214 A of the second resonance coil  214 . 
     For example, a copper pipe, a copper thin plate, an aluminum pipe, an aluminum thin plate and a material obtained by depositing copper or aluminum on a polymer belt may be used as a material constituting each of the first resonance coil  212  and the second resonance coil  214 . Each of the first resonance coil  212  and the second resonance coil  214  is supported by a plurality of supports (not shown) of a plate shape and made of an insulating material, which are provided on an upper end surface of a base plate  248  so as to extend vertically. 
     The both ends of the first resonance coil  212  are electrically grounded. One end of the first resonance coil  212  (for example, the upper end  212 B shown in  FIGS.  2 ,  4  and  8   ) is grounded via a movable tap  300  in order to fine-tune the electrical length of the first resonance coil  212  when the substrate processing apparatus  100  is newly installed or process conditions of the substrate processing apparatus  100  are changed, and the other end of the first resonance coil  212  (for example, the lower end  212 C shown in  FIGS.  1  through  4 ,  7  and  8   ) is grounded as a fixed ground. In addition, in order to fine-tune impedance (or the electrical length) of the first resonance coil  212  when the substrate processing apparatus  100  is newly installed or the process conditions of the substrate processing apparatus  100  are changed, a power feeder (not shown) is constituted by a movable tap  305  between the grounded ends of the first resonance coil  212 . Further, a position of the movable tap  305  may be adjusted in order for the resonance characteristics of the first resonance coil  212  to become approximately the same as those of the RF power supply  273 . Since the first resonance coil  212  includes a variable ground structure (that is, the movable tap  300 ) and a variable power supply feeding structure (that is, the power feeder constituted by the movable tap  305 ), it is possible to easily adjust a resonance frequency and a load impedance of the process chamber  201 . The upper end  212 B of the first resonance coil  212  according to the present embodiments is an example of a first ground connection portion according to the technique of the present disclosure. Further, the lower end  212 C of the first resonance coil  212  according to the present embodiments is an example of a second ground connection portion according to the technique of the present disclosure. When the vicinity of the upper end  212 B of the first resonance coil  212  is grounded, a location in the vicinity of the upper end  212 B becomes a grounding point and serves as the first ground connection portion. In addition, when the vicinity of the lower end  212 C of the first resonance coil  212  is grounded, a location in the vicinity of the lower end  212 C becomes a grounding point and serves as the second ground connection portion. 
     The both ends of the second resonance coil  214  are electrically grounded. One end of the second resonance coil  214  (for example, the upper end  214 B shown in  FIGS.  6  and  8   ) is grounded via a movable tap  302  in order to fine-tune the electrical length of the second resonance coil  214  when the substrate processing apparatus  100  is newly installed or the process conditions of the substrate processing apparatus  100  are changed, and the other end of the second resonance coil  214  (for example, the lower end  214 C shown in  FIGS.  1 ,  6 ,  7  and  8   ) is grounded as a fixed ground. In addition, in order to fine-tune the impedance (or the electrical length) of the second resonance coil  214  when the substrate processing apparatus  100  is newly installed or the process conditions of the substrate processing apparatus  100  are changed, a power feeder (not shown) is constituted by a movable tap  306  between the grounded ends of the second resonance coil  214 . Further, a position of the movable tap  306  may be adjusted in order for the resonance characteristics of the second resonance coil  214  to become approximately the same as those of the RF power supply  283 . Since the second resonance coil  214  includes a variable ground structure (that is, the movable tap  302 ) and a variable power supply feeding structure (that is, the power feeder constituted by the movable tap  306 ), it is possible to easily adjust the resonance frequency and the load impedance of the process chamber  201 . The upper end  214 B of the second resonance coil  214  according to the present embodiments is an example of a third ground connection portion according to the technique of the present disclosure. Further, the lower end  214 C of the second resonance coil  214  according to the present embodiments is an example of a fourth ground connection portion according to the technique of the present disclosure. When the vicinity of the upper end  214 B of the second resonance coil  214  is grounded, a location in the vicinity of the upper end  214 B becomes a grounding point and serves as the third ground connection portion. In addition, when the vicinity of the lower end  214 C of the second resonance coil  214  is grounded, a location in the vicinity of the lower end  214 C becomes a grounding point and serves as the fourth ground connection portion. 
     A waveform adjustment circuit  308  constituted by a resonance coil (not shown) and a shield (not shown) is inserted into one end (or the other end or the both ends) of the first resonance coil  212  so that the phase current and the opposite phase current flow symmetrically with respect to an electrical midpoint of the first resonance coil  212 . The waveform adjustment circuit  308  is configured to be open by setting the first resonance coil  212  to an electrically disconnected state or an electrically equivalent state. In addition, an end portion of the first resonance coil  212  may be non-grounded by a choke series resistor, or may be DC-connected to a fixed reference potential. 
     In addition, a waveform adjustment circuit  309  constituted by a resonance coil (not shown) and a shield (not shown) is inserted into one end (or the other end or the both ends) of the second resonance coil  214  so that the phase current and the opposite phase current flow symmetrically with respect to an electrical midpoint of the second resonance coil  214 . The waveform adjustment circuit  309  is configured to be open by setting the second resonance coil  214  to an electrically disconnected state or an electrically equivalent state. In addition, an end portion of the second resonance coil  214  may be non-grounded by a choke series resistor, or may be DC-connected to a fixed reference potential. 
     For example, the waveform adjustment circuit  308  or  309  may be arranged on at least one of the first resonance coil  212  or the second resonance coil  214 . According to the present embodiments, as the waveform adjustment circuit  308  or  309 , for example, a variable capacitor may be used, or a wire (coil) made of a conductor may be used. 
     A shield plate  223  is provided to shield an electric field outside of the first resonance coil  212  and/or the second resonance coil  214  and to form a capacitive component (also referred to as a “C component”) of the first resonance coil  212  or the second resonance coil  214  appropriate for constructing a resonance circuit between the shield plate  223  and the first resonance coil  212  or between the shield plate  223  and the second resonance coil  214 . In general, the shield plate  223  is made of a conductive material such as an aluminum alloy, and is of a cylindrical shape. The shield plate  223  is disposed, for example, about 5 mm to 150 mm apart from an outer periphery of each of the first resonance coil  212  and the second resonance coil  214 . 
     A first plasma generator according to the present embodiments is constituted mainly by the first resonance coil  212 , the RF sensor  272  and the matcher  274 . In addition, the first plasma generator may further include the RF power supply  273 . Further, a second plasma generator according to the present embodiments is constituted mainly by the second resonance coil  214 , the RF sensor  282  and the matcher  284 . In addition, the second plasma generator may further include the RF power supply  283 . The first plasma generator and the second plasma generator may be collectively referred to as a “plasma generator”. 
     Hereinafter, a principle of generating the plasma in the substrate processing apparatus  100  of the present embodiments and the properties of the generated plasma will be described. Since the principles of generating the plasma by each of the first resonance coil  212  and the second resonance coil  214  are the same, the principle of generating the plasma by the first resonance coil  212  will be described hereafter as an example (see  FIGS.  3  through  5   ). 
     A plasma generation circuit constituted by the first resonance coil  212  is configured as an RLC parallel resonance circuit. When the wavelength of the RF power supplied from the RF power supply  273  and the electrical length of the first resonance coil  212  are the same, the resonance condition of the first resonance coil  212  is that a reactance component generated by a capacitance component or an inductive component of the first resonance coil  212  is canceled out to become a pure resistance. However, when the plasma is generated in the plasma generation circuit described above, an actual resonance frequency may fluctuate slightly depending on conditions such as a variation (change) in a capacitive coupling between a voltage portion of the first resonance coil  212  and the plasma, a variation in an inductive coupling between the plasma generation space  201 A and the plasma and an excitation state of the plasma. 
     Therefore, in the substrate processing apparatus  100  according to the present embodiments, in order to compensate for a resonance shift in the first resonance coil  212  when the plasma is generated by adjusting the power supplied from the RF power supply  273 , the RF sensor  272  is configured to detect the power of the reflected wave from the first resonance coil  212  when the plasma is generated, and the matcher  274  is configured to correct the output of the RF power supply  273  based on the detected power of the reflected wave. 
     Specifically, the matcher  274  is configured to increase or decrease the impedance or the output frequency of the RF power supply  273  such that the power of the reflected wave is minimized based on the power of the reflected wave from the first resonance coil  212  detected by the RF sensor  272  when the plasma is generated. In case the impedance is controlled by the matcher  274 , the matcher  274  is constituted by a variable capacitor control circuit (not shown) capable of correcting a preset impedance. In case the output frequency of the RF power supply  273  is controlled by the matcher  274 , the matcher  274  is constituted by a frequency control circuit (not shown) capable of correcting a preset oscillation frequency of the RF power supply  273 . For example, the RF power supply  273  and the matcher  274  may be provided integrally as a single body. 
     According to the configuration related to the first resonance coil  212  according to the present embodiments, the RF power whose frequency is equal to the actual resonance frequency of the first resonance coil  212  combined with the plasma is supplied to the first resonance coil  212  (or the RF power is supplied to match an actual impedance of the first resonance coil  212  combined with the plasma). Therefore, the standing wave in which the phase voltage thereof and the opposite phase voltage thereof are always canceled out by each other is generated in the first resonance coil  212  (see  FIG.  3   ). For example, when the wavelength of the RF power and the electrical length of the first resonance coil  212  are the same, the highest phase current is generated at an electrical midpoint of the first resonance coil  212  (node with zero voltage). Specifically, when the RF power is supplied from the RF power supply  273  to the first resonance coil  212 , for example, a current standing wave and a voltage standing wave whose wavelengths are equal to the wavelength of the RF power supplied from the RF power supply  273  are generated between both ends of a line of the first resonance coil  212 . Among waveforms on a right portion of  FIG.  3   , a broken line illustrates the current and a solid line illustrates the voltage. As shown by the waveform on the right portion of  FIG.  3   , an amplitude of the current standing wave is maximized at the both ends of the first resonance coil  212  and a midpoint (that is, the electrical midpoint) of the first resonance coil  212 . Therefore, a donut-shaped induction plasma (which is an inductively coupled plasma (ICP))  310  of an extremely low electric potential is generated in the vicinity of the electrical midpoint of the first resonance coil  212 . The donut-shaped ICP  310  is hardly capacitively coupled with walls of the process chamber  201  or the susceptor  217 . Specifically, a high frequency magnetic field is generated in the vicinity of the electrical midpoint of the first resonance coil  212  where the amplitude of the current standing wave is maximized, and a plasma discharge of the process gas supplied into the plasma generation space  201 A in the upper vessel  210  is generated by a high frequency electromagnetic field induced by the high frequency magnetic field. The plasma of the process gas is generated in the vicinity of the electrical midpoint of the first resonance coil  212  by exciting the process gas discharged by the high frequency electromagnetic field. Hereinafter, the plasma of the process gas generated by the high frequency electromagnetic field generated in the vicinity of a location (region) where the amplitude of the current is great as described above may also be referred to as the “ICP”. As shown in  FIG.  4   , the ICP is generated in a donut shape in a region in the vicinity of the electrical midpoint of the first resonance coil  212  in a space along an inner wall surface of the upper vessel  210 . Thereby, the ICP whose plasma density is uniform in a direction parallel to a surface of the wafer  200  can be generated. Similarly, the induction plasma is also generated at the both axial ends of the first resonance coil  212  according to the same principle. 
     Subsequently, an internal state of the process furnace  202  when the plasma is generated using the first resonance coil  212  and the second resonance coil  214  will be described. 
     In the substrate processing apparatus  100  according to the present embodiments shown in  FIG.  8   , the first resonance coil  212  and the second resonance coil  214  are respectively provided around the plasma generation space  201 A, similar to a case where the first resonance coil  212  alone is provided as shown in  FIG.  4   . For example, when the RF power is supplied to the first resonance coil  212  while the process gas is supplied to the plasma generation space  201 A, the voltage and the current are generated as shown on a right portion of  FIG.  7    by the principle described above, and the ICP  310  is generated in the plasma generation space  201 A as shown in  FIG.  8   . 
     Similarly, when the RF power is supplied to the second resonance coil  214  while the process gas is supplied to the plasma generation space  201 A, the voltage and the current are generated as shown on a left portion of  FIG.  7    by the principle described above, and an ICP  312  is generated in the plasma generation space  201 A as shown in  FIG.  8   . 
     By using a plurality of resonance coils (for example, the first resonance coil  212  and the second resonance coil  214 ), it is possible to generate a large amount of the plasma as compared with a case where a single resonance coil (for example, the first resonance coil  212  alone) is used to generate the plasma. That is, it is possible to generate a large amount of radical components in the plasma. 
     According to the present embodiments, the winding diameter D 2  of the second resonance coil  214  is set to be different from the winding diameter D 1  of the first resonance coil  212 . Therefore, as shown in  FIG.  7   , the peak of the voltage distribution of the first resonance coil  212  and the peak of the voltage distribution of the second resonance coil  214  are displaced with each other in the radial direction. That is, the peak of the voltage distribution of the first resonance coil  212  and the peak of the voltage distribution of the second resonance coil  214  do not overlap with each other. By making the peaks of the voltage distributions of the two resonance coils (that is, the first resonance coil  212  and the second resonance coil  214 ) to be apart from each other as described above, it is possible to uniformize a density of the highly concentrated induction plasma along the radial direction (see  FIG.  9   ). Thereby, it is possible to realize a uniformity of the density of induction plasma on a surface of the substrate (that is, on the surface of the wafer  200 ). 
     Further, the second resonance coil  214  according to the present embodiments is configured such that, in the direction (horizontal direction) perpendicular to the axial direction, the peak of the voltage distribution thereof does not overlap with the peak of the voltage distribution of the first resonance coil  212 . By making the peaks of the voltage distributions of the two resonance coils in the horizontal direction to be apart from each other as described above, it is possible to uniformize the density of the plasma. For example, as shown in  FIG.  9   , by separately forming the ICPs (that is, the ICP  310  and the ICP  312 ) using the two resonance coils, it is possible to increase an amount of the plasma in the radial direction. 
     Further, the second resonance coil  214  according to the present embodiments is configured such that, in the axial direction (vertical direction), the peak of the voltage distribution thereof does not overlap with the peak of the voltage distribution of the first resonance coil  212 . By making the peaks of the voltage distributions of the two resonance coils in the vertical direction to be apart from each other as described above, it is possible to supplement a state of one induction plasma by the other induction plasma. Therefore, it is possible to extend a lifetime of the entirety of the induction plasma. 
     Further, according to the present embodiments, the first arrangement region FA and the second arrangement region SA are provided on the outer periphery of the process vessel  203 . In addition, the first resonance coil  212  alone is continuously arranged in the second arrangement region SA. Therefore, it is possible to adjust a physical length of a coil length with respect to the plasma generation space  201 A. Thereby, it is possible to secure a flexibility in the design. 
     Further, according to the present embodiments, the winding diameter D 1  of the first resonance coil  212  is set to be smaller than the winding diameter D 2  of the second resonance coil  214 . It is possible to form the peak of the voltage distribution using the first resonance coil  212  with the winding diameter D 1  smaller than the winding diameter D 2  of the second resonance coil  214 . Thereby, it is possible to supply the induction plasma whose density is high to a central region of the substrate (that is, the wafer  200 ). 
     Further, the second arrangement region SA according to the present embodiments is provided closer to the susceptor  217  on which the wafer  200  is placed in the process vessel  203  than the first arrangement region FA in the axial direction (vertical direction). According to the present embodiments, for example, by reducing the winding diameter of the resonance coil provided closer to the susceptor  217  (that is, by reducing the winding diameter D 1  of the first resonance coil  212 ), it is possible to easily supply the plasma to the central region of the wafer  200  directly below the resonance coil provided closer to the susceptor  217 . 
     Further, the process vessel  203  according to the present embodiments is provided with the exhauster capable of exhausting the process gas from the outer periphery of the susceptor  217 . As a result, it is possible to diffuse a flow of the induction plasma supplied to the central region of the wafer  200  toward the outer periphery of the susceptor  217 . That is, it is possible to diffuse the plasma whose density is high supplied to the central region of the wafer  200  in an outer peripheral direction, and therefore, it is possible to uniformize a processing of the wafer  200  on the surface of the wafer  200 . 
     Further, according to the present embodiments, in the first arrangement region FA, the conductor  212 A of the first resonance coil  212  and the conductor  214 A of the second resonance coil  214  are separated from each other at the distance such that no arc discharge is generated therebetween. Further, in the second arrangement region SA, the conductor  212 A of the first resonance coil  212  is provided such that no arc discharge is generated between portions of the conductor  212 A wounded the plurality of times with a gap. For example, when a voltage difference between the resonance coils is equal to or greater than a threshold value, the arc discharge may be generated therebetween, and thereby, the electric power may leak. When the electric power leaks, a desired induction plasma cannot be provided. On the other hand, according to the present embodiments, the conductor  212 A and the conductor  214 A are separated from each other at the distance such that no arc discharge is generated therebetween. Thereby, it is possible to suppress a leakage of the electric power. As a result, it is possible to provide the desired induction plasma. 
     Further, the first resonance coil  212  according to the present embodiments is configured such that the electrical length between the both ends thereof grounded is a multiple of the wavelength of the RF power supplied to the first resonance coil  212 . By grounding the both ends of the first resonance coil  212  as described above, it is possible to provide the multiple of the wavelength of the RF power supplied to the first resonance coil  212 . Thereby, it is possible to provide a sine curve of the voltage shown in  FIG.  7   . As a result, it is possible to easily control the peak of the voltage distribution of the first resonance coil  212 . 
     Further, the second resonance coil  214  according to the present embodiments is configured such that the electrical length between the both ends thereof grounded is a multiple of the wavelength of the RF power supplied to the second resonance coil  214 . By grounding the both ends of the second resonance coil  214  as described above, it is possible to provide the multiple of the wavelength of the RF power supplied to the second resonance coil  214 . Thereby, it is possible to provide a sine curve of the voltage shown in  FIG.  7   . As a result, it is possible to easily control the peak of the voltage distribution of the second resonance coil  214 . 
     Further, according to the present embodiments, the waveform adjustment circuits  308  and  309  configured to correct the electrical length are connected to the first resonance coil  212  and the second resonance coil  214 , respectively, such that the electrical length of the first resonance coil  212  and the electrical length of the second resonance coil  214  are equal to each other. When the electrical lengths described above cannot be adjusted by grounding, the electrical lengths can be adjusted by using the waveform adjustment circuits  308  and  309  as described above. 
     Further, according to the present embodiments, a position of the grounded upper end  212 B of the first resonance coil  212  in the vertical direction is set to be different from a position of the grounded upper end  214 B of the second resonance coil  214 . By setting grounding heights of the upper ends of the resonance coils different from each other as described above, it is possible to more reliably make positions of the peaks of the voltage distributions to be more reliably spaced apart from each other. 
     Further, according to the present embodiments, a position of the grounded lower end  212 C of the first resonance coil  212  in the vertical direction is set to be different from a position of the grounded lower end  214 C of the second resonance coil  214 . By setting grounding heights of the lower ends of the resonance coils different from each other as described above, it is possible to more reliably make the positions of the peaks of the voltage distributions to be more reliably spaced apart from each other. 
     Further, according to the present embodiments, the frequency of the RF power generated from the RF power supply  273  connected to the first resonance coil  212  is the same as the frequency of the RF power generated from the RF power supply  283  connected to the second resonance coil  214 . When the frequencies of the RF power supply  273  and the RF power supply  283  are the same as described above, it is possible to set the wavelengths of the RF power supply  273  and the RF power supply  283  to be the same. As a result, it is possible to easily control the positions of the peaks of the voltage distributions. 
     Further, according to the present embodiments, a controller  221  described later controls components constituting the substrate processing apparatus  100  to supply the process gas into the process chamber  201  while supplying the RF power to the first resonance coil  212  and the second resonance coil  214 . Thereby, it is possible to generate two types of the induction plasma in the plasma generation space  201 A. As a result, it is possible to more reliably uniformize the induction plasma. 
     Controller 
     The controller  221  serving as a control structure is configured to control the components constituting the substrate processing apparatus  100 . For example, the controller  221  is configured to control the APC valve  242 , the valve  243 B and the vacuum pump  246  via a signal line “A” shown in  FIG.  1   . For example, the controller  221  is configured to control the susceptor elevator  268  via a signal line “B” shown in  FIG.  1   . For example, the controller  221  is configured to control a heater power regulator  276  and the variable impedance regulator  275  via a signal line “C” shown in  FIG.  1   . For example, the controller  221  is configured to control the gate valve  244  via a signal line “D” shown in  FIG.  1   . For example, the controller  221  is configured to control the RF sensor  272 , the RF power supply  273 , the matcher  274 , the RF sensor  282 , the RF power supply  283  and the matcher  284  via a signal line “E” shown in  FIG.  1   . For example, the controller  221  is configured to control the MFCs  252 A,  252 B and  252 C, the valves  253 A,  253 B and  253 C and the valve  243 A via a signal line “F” shown in  FIG.  1   . 
     As shown in  FIG.  10   , the controller  221  (control structure) is constituted by a computer including a CPU (Central Processing Unit)  221 A, a RAM (Random Access Memory)  221 B, a memory  221 C and an I/O port  221 D. The RAM  221 B, the memory  221 C and the I/O port  221 D may exchange data with the CPU  221 A through an internal bus  221 E. For example, an input/output device  225  constituted by components such as a touch panel and a display may be connected to the controller  221 . 
     For example, the memory  221 C is configured by a component such as a flash memory and a hard disk drive (HDD). For example, a control program configured to control the operation of the substrate processing apparatus  100  or a process recipe containing information on the sequences and conditions of the substrate processing described later is readably stored in the memory  221 C. The process recipe is obtained by combining steps of the substrate processing described later such that the controller  221  can execute the steps to acquire a predetermined result, and functions as a program. Hereinafter, the process recipe and the control program are collectively or individually referred to as a “program”. Thus, in the present specification, the term “program” may refer to the process recipe alone, may refer to the control program alone, or may refer to both of the process recipe and the control program. The RAM  221 B functions as a memory area (work area) where a program or data read by the CPU  221 A is temporarily stored. 
     The I/O port  221 D is electrically connected to the components described above such as the MFCs  252 A through  252 C, the valves  253 A through  253 C, the valves  243 A and  243 B, the gate valve  244 , the APC valve  242 , the vacuum pump  246 , the RF sensor  272 , the RF power supply  273 , the matcher  274 , the RF sensor  282 , the RF power supply  283 , the matcher  284 , the susceptor elevator  268 , the variable impedance regulator  275  and the heater power regulator  276 . 
     The CPU  221 A is configured to read and execute the control program stored in the memory  221 C, and to read the process recipe stored in the memory  221 C in accordance with an instruction such as an operation command inputted via the input/output device  225 . The CPU  221 A is configured to control the operation of the substrate processing apparatus  100  according to the read process recipe. For example, the CPU  221 A is configured to perform an operation of adjusting an opening degree of the APC valve  242 , an opening and closing operation of the valve  243 B and a start and stop of the vacuum pump  246  via the I/O port  221 D and the signal line A according to the read process recipe. For example, the CPU  221 A is configured to perform an elevating and lowering operation of the susceptor elevator  268  via the signal line B according to the read process recipe. For example, the CPU  221 A is configured to perform a power supply amount adjusting operation (temperature adjusting operation) on the heater  217 B by the heater power regulator  276  and an impedance adjusting operation by the variable impedance regulator  275  via the signal line C according to the read process recipe. For example, the CPU  221 A is configured to perform an opening and closing operation of the gate valve  244  via the signal line D according to the read process recipe. For example, the CPU  221 A is configured to perform a controlling operation of the RF sensor  272 , the matcher  274 , the RF power supply  273 , the RF sensor  282 , the matcher  284  and the RF power supply  283  via the signal line E according to the read process recipe. For example, the CPU  221 A is configured to perform flow rate adjusting operations for various gases by the MFCs  252 A,  252 B and  252 C and opening and closing operations of the valves  253 A,  253 B,  253 C and  243 A via the signal line F according to the read process recipe. The CPU  221 A may control operations of components of the substrate processing apparatus  100  other than the components described above. 
     The controller  221  may be embodied by installing the above-described program stored in an external memory  226  into a computer. For example, the external memory  226  may include a magnetic tape, a magnetic disk such as a flexible disk and a hard disk, an optical disk such as a CD and a DVD, a magneto-optical disk such as an MO and a semiconductor memory such as a USB memory and a memory card. The memory  221 C or the external memory  226  may be embodied by a non-transitory computer readable recording medium. Hereafter, the memory  221 C and the external memory  226  are collectively or individually referred to as a “recording medium”. In the present specification, the term “recording medium” may refer to the memory  221 C alone, may refer to the external memory  226  alone, and may refer to both of the memory  221 C and the external memory  226 . Instead of the external memory  226 , a communication means such as the Internet and a dedicated line may be used for providing the program to the computer. 
     (2) Substrate Processing 
     Subsequently, the substrate processing according to the present embodiments will be described with reference to  FIG.  11   .  FIG.  11    is a flowchart schematically illustrating the substrate processing according to the present embodiments. For example, the substrate processing, which is a part of a manufacturing process of a semiconductor device such as a flash memory, is performed by the substrate processing apparatus  100  described above. In the following description, the operations of the components constituting the substrate processing apparatus  100  are controlled by the controller  221 . 
     For example, although not shown, a trench is formed in advance on the surface of the wafer  200  to be processed by the substrate processing according to the present embodiments. In addition, the trench includes a concave-convex portion of a high aspect ratio. According to the present embodiments, for example, the oxidation process serving as a process using the plasma (that is, the substrate processing) is performed to a silicon layer exposed on an inner wall of the trench. 
     Substrate Loading Step S 110   
     First, the wafer  200  is transferred (loaded) into the process chamber  201 . Specifically, the susceptor  217  is lowered to a position for transferring the wafer  200  (also referred to as a “transfer position”) by the susceptor elevator  268  such that the wafer lift pins  266  pass through the through-holes  217 A of the susceptor  217 . As a result, the wafer lift pins  266  protrude from a surface of the susceptor  217  by a predetermined height. 
     Subsequently, the gate valve  244  is opened, and the wafer  200  is transferred (loaded) into the process chamber  201  using a wafer transfer device (not shown) from a vacuum transfer chamber (not shown) provided adjacent to the process chamber  201 . The wafer  200  loaded into the process chamber  201  is placed on and supported in a horizontal orientation by the wafer lift pins  266  protruding from the surface of the susceptor  217 . After the wafer  200  is loaded into the process chamber  201  and supported by the wafer lift pins  266 , the wafer transfer device is retracted to an outside of the process chamber  201 . Then, the gate valve  244  is closed to seal (close) an inside of the process chamber  201  hermetically. Thereafter, by elevating the susceptor  217  using the susceptor elevator  268 , the wafer  200  is placed on and supported by an upper surface of the susceptor  217 . 
     Temperature Elevation and Vacuum Exhaust Step S 120   
     Subsequently, a temperature of the wafer  200  loaded into the process chamber  201  is elevated. The heater  217 B is heated in advance, and the wafer  200  is held by the susceptor  217  in which the heater  217 B is embedded. Thereby, for example, the wafer  200  is heated to a predetermined temperature within a range from 150° C. to 750° C. Further, while the wafer  200  is being heated, the vacuum pump  246  vacuum-exhausts the inner atmosphere of the process chamber  201  through the gas exhaust pipe  231  such that an inner pressure of the process chamber  201  reaches and is maintained at a predetermined pressure. The vacuum pump  246  continuously vacuum-exhausts the inner atmosphere of the process chamber  201  at least until a substrate unloading step S 160  described later is completed. 
     Reactive Gas Supply Step S 130   
     Subsequently, the oxygen-containing gas and the hydrogen-containing gas are supplied into the process chamber  201  as the reactive gas. Specifically, the valves  253 A and  253 B are opened to start a supply of the oxygen-containing gas and a supply of the hydrogen-containing gas, respectively, into the process chamber  201  while flow rates of the oxygen-containing gas and the hydrogen-containing gas are adjusted by the MFCs  252 A and  252 B, respectively. In the reactive gas supply step S 130 , for example, the flow rate of the oxygen-containing gas is set to a predetermined flow rate within a range from 20 sccm to 2,000 sccm. In addition, for example, the flow rate of the hydrogen-containing gas is set to a predetermined flow rate within a range from 20 sccm to 1,000 sccm. 
     In the reactive gas supply step S 130 , the inner atmosphere of the process chamber  201  is exhausted by adjusting the opening degree of the APC valve  242  such that, for example, the inner pressure of the process chamber  201  is at a predetermined pressure within a range from 1 Pa to 250 Pa. The oxygen-containing gas and the hydrogen-containing gas are continuously supplied into the process chamber  201  while appropriately exhausting the inner atmosphere of the process chamber  201  until a plasma processing step S 140  described later is completed. 
     For example, as the oxygen-containing gas, a gas such as oxygen (O 2 ) gas, nitrogen peroxide (N2O) gas, nitrogen monoxide (NO) gas, nitrogen dioxide (NO2) gas, ozone (O3) gas, water vapor (H2O gas), carbon monoxide (CO) gas and carbon dioxide (CO2) gas may be used. In addition, one or more of the gases described above may be used as the oxygen-containing gas. 
     Further, for example, as the hydrogen-containing gas, a gas such as hydrogen (H2) gas, deuterium (D2) gas, the H2O gas and ammonia (NH3) gas may be used. In addition, one or more of the gases described above may be used as the hydrogen-containing gas. When the H2O gas is used as the oxygen-containing gas, it is preferable that a gas other than the H2O gas is used as the hydrogen-containing gas. In addition, when the H2O gas is used as the hydrogen-containing gas, it is preferable that a gas other than the H2O gas is used as the oxygen-containing gas. 
     For example, as the inert gas, nitrogen (N2) gas may be used. In addition, a rare gas such as argon (Ar) gas, helium (He) gas, neon (Ne) gas and xenon (Xe) gas may be used as the inert gas. For example, one or more of the gases described above may be used as the inert gas. 
     Plasma Processing Step S 140   
     In the plasma processing step S 140 , first, while supplying the process gas through the gas supplier, the RF power is supplied from the RF power supplier  271  to the first resonance coil  212  without supplying the RF power from the RF power supplier  281  to the second resonance coil  214 . Specifically, when the inner pressure of the process chamber  201  is stabilized, a supply of the RF power is started for the first resonance coil  212  from the RF power supply  273  via the RF sensor  272 . 
     Thereby, a high frequency electromagnetic field is formed in the plasma generation space  201 A to which the oxygen-containing gas and the hydrogen-containing gas are supplied. As a result, the donut-shaped ICP  310  whose plasma density is the highest at a height corresponding to the electrical midpoint of the first resonance coil  212  in the plasma generation space  201 A is excited by the high frequency electromagnetic field. The oxygen-containing gas and the hydrogen-containing gas are excited into a plasma state and dissociate. As a result, reactive species such as oxygen radicals containing oxygen (oxygen active species), oxygen ions, hydrogen radicals containing hydrogen (hydrogen active species) and hydrogen ions can be generated. 
     The radicals generated by the induction plasma and non-accelerated ions are uniformly supplied into the trench of the wafer  200  placed on the susceptor  217  in the substrate processing space  201 B. Then, the radicals and the ions uniformly supplied into the trench of the wafer  200  uniformly react with a layer (for example, the silicon layer) formed on a surface of the inner wall of the trench. Thereby, the layer formed on the surface of the inner wall of the trench is modified into an oxide layer (for example, a silicon oxide layer) whose step coverage is good. 
     After a predetermined process time (for example, 10 seconds to 300 seconds) has elapsed, the supply of the RF power from the RF power supply  273  is stopped. 
     Subsequently, while supplying the process gas through the gas supplier, the RF power is supplied from the RF power supplier  281  to the second resonance coil  214  without supplying the RF power from the RF power supplier  271  to the first resonance coil  212 . Specifically, when the inner pressure of the process chamber  201  is stabilized, a supply of the RF power is started for the second resonance coil  214  from the RF power supply  283  via the RF sensor  282 . 
     Thereby, a high frequency electromagnetic field is formed in the plasma generation space  201 A to which the oxygen-containing gas and the hydrogen-containing gas are supplied. As a result, the donut-shaped ICP  312  whose plasma density is the highest at a height corresponding to the electrical midpoint of the second resonance coil  214  in the plasma generation space  201 A is excited by the high frequency electromagnetic field. The oxygen-containing gas and the hydrogen-containing gas are excited into the plasma state and dissociate. As a result, the reactive species such as the oxygen radicals containing oxygen (the oxygen active species), the oxygen ions, the hydrogen radicals containing hydrogen (hydrogen active species) and the hydrogen ions can be generated. 
     The radicals generated by the induction plasma (that is, the donut-shaped ICP  312 ), the radicals generated by the induction plasma (that is, the donut-shaped ICP  310 ) generated by the first resonance coil  212  and whose lifetime is extended in the present step and non-accelerated ions are uniformly supplied into the trench of the wafer  200  placed on the susceptor  217  in the substrate processing space  201 B. Then, the radicals and the ions uniformly supplied into the trench of the wafer  200  uniformly react with the layer (for example, the silicon layer) formed on the surface of the inner wall of the trench. Thereby, the layer formed on the surface of the inner wall of the trench is modified into the oxide layer (for example, the silicon oxide layer) whose step coverage is good. 
     After a predetermined process time (for example, 10 seconds to 300 seconds) has elapsed, the supply of the RF power from the RF power supply  283  is stopped. Thereby, the plasma discharge in the process chamber  201  is stopped. 
     In addition, the valves  253 A and  253 B are closed to stop the supply of the oxygen-containing gas and the supply of the hydrogen-containing gas into the process chamber  201 . Thereby, the plasma processing step S 140  is completed. 
     Vacuum Exhaust Step S 150   
     After the supply of the oxygen-containing gas and the supply of the hydrogen-containing gas are stopped, the inner atmosphere of the process chamber  201  is vacuum-exhausted through the gas exhaust pipe  231 . Thereby, the gas such as the oxygen-containing gas, the hydrogen-containing gas and an exhaust gas generated from the reaction therebetween in the process chamber  201  is exhausted to the outside of the process chamber  201 . Thereafter, the opening degree of the APC valve  242  is adjusted such that the inner pressure of the process chamber  201  is adjusted to the same pressure as that of the vacuum transfer chamber (not shown) provided adjacent to the process chamber  201 . The vacuum transfer chamber serves as an unloading destination of the wafer  200 . 
     Substrate Unloading Step S 160   
     After the inner pressure of the process chamber  201  is adjusted to a predetermined pressure, the susceptor  217  is lowered to the transfer position of the wafer  200  until the wafer  200  is supported by the wafer lift pins  266 . Then, the gate valve  244  is opened, and the wafer  200  is transferred (unloaded) out of the process chamber  201  by using the wafer transfer device (not shown). 
     Thereby, the substrate processing according to the present embodiments is completed. 
     Other Embodiments 
     While the technique of the present disclosure is described in detail by way of the embodiments described above, the technique of the present disclosure is not limited thereto. For example, the embodiments described above may be appropriately combined. 
     For example, the above-described embodiments are described by way of an example in which the second arrangement region SA is provided closer to the susceptor  217  than the first arrangement region FA in the up-and-down direction of the substrate processing apparatus  100  (that is, the vertical direction). However, the technique of the present disclosure is not limited thereto. For example, the second arrangement region SA may be provided farther from the susceptor  217  than the first arrangement region FA in the up-and-down direction of the substrate processing apparatus  100  (that is, the vertical direction). 
     For example, the above-described embodiments are described by way of an example in which the first arrangement region FA and the second arrangement region SA are provided on the outer periphery of the process vessel  203  as shown in  FIG.  8   . However, the technique of the present disclosure is not limited thereto. For example, as shown in  FIG.  12   , a third arrangement region TA may be provided opposite to the first arrangement region FA with the second arrangement region SA provided therebetween. In the third arrangement region TA, the conductor  212 A of the first resonance coil  212  and the conductor  214 A of the second resonance coil  214  are alternately arranged in the vertical direction (that is, the axial direction of each resonance coil). In such a case, by grounding the both ends of the first resonance coil  212 , it is possible to provide the multiple of the wavelength of the RF power supplied to the first resonance coil  212 . Thereby, it is possible to provide the sine curve of the voltage. As a result, it is possible to easily control the peak of the voltage distribution of the first resonance coil  212 . 
     For example, the above-described embodiments are described by way of an example in which the axial length of the coil portion of the first resonance coil  212  is set to be different from the axial length of the coil portion of the second resonance coil  214 . However, the technique of the present disclosure is not limited thereto. For example, the axial length of the coil portion of the first resonance coil  212  may be the same as the axial length of the coil portion of the second resonance coil  214 . In such a case, for example, the first resonance coil  212  and the second resonance coil  214  may be arranged such that the first resonance coil  212  entirely overlaps with the second resonance coil  214 , or such that a lower portion of the first resonance coil  212  overlaps with an upper portion of the second resonance coil  214 . Further, even when the axial length of the coil portion of the first resonance coil  212  is set to be different from the axial length of the coil portion of the second resonance coil  214 , the first resonance coil  212  and the second resonance coil  214  may be arranged such that a part of the coil portion of the first resonance coil  212  in the axial direction overlaps with a part of the coil portion of the second resonance coil  214  in the axial direction. 
     For example, the above-described embodiments are described by way of an example in which the process chamber  201  defined by the process vessel  203  includes the plasma generation room and the substrate processing room (That is, the plasma generation room and the substrate processing room are configured by the same process vessel  203 ). However, the technique of the present disclosure is not limited thereto. For example, the plasma generation room and the substrate processing room may be configured as separate vessels. 
     For example, the above-described embodiments are described by way of an example in which the oxidation process using the plasma is performed onto the surface of the substrate. However, the technique of the present disclosure is not limited thereto. For example, a nitridation process using a nitrogen-containing gas as the process gas may be performed. Further, the technique of the present disclosure is not limited to the nitridation process and the oxidation process, and may be applied to other processing techniques of processing the substrate using the plasma. For example, the technique of the present disclosure may be applied to a process such as a modification process onto a film formed on the surface of the substrate, a doping process, a reduction process of an oxide film, an etching process with respect to the film and a photoresist ashing process, which are performed by using the plasma. 
     For example, the above-described embodiments are described by way of an example in which the two resonance coils are used. However, the technique of the present disclosure is not limited thereto. For example, three or more resonance coils may be used. 
     For example, the above-described embodiments are described by way of the embodiments and modified examples described above. However, the technique of the present disclosure is not limited thereto. It is apparent to the person skilled in the art that the technique of the present disclosure may be modified in various ways without departing from the scope thereof. 
     According to some embodiments of the present disclosure, it is possible to improve the uniformity of the substrate processing on the surface of the substrate.