Plasma processing device

Abstract

Disclosed is a plasma processing device comprising: a plasma processing chamber; a substrate support part that is disposed in the plasma processing chamber; a dielectric window that is disposed above the substrate support part and has an opening penetrating the dielectric window in a central portion of the dielectric window; a gas injector that extends through the opening of the dielectric window and is attached to the central portion of the dielectric window; an antenna that is disposed above the dielectric window to surround the gas injector; an RF power supply that is electrically connected to the antenna; and a heater unit that is attached to the gas injector so as to heat the dielectric window via the gas injector.

Description

Plasma processing apparatus 【0001】 An exemplary embodiment of the present disclosure relates to a plasma processing apparatus. 【0002】 The plasma processing apparatus described in Patent Document 1 includes a chamber, a dielectric window formed at the upper part of the chamber and having an opening at the central portion, a gas injection part installed at the opening of the dielectric window, and an antenna provided around the gas injection part. The antenna includes an inner coil provided around the gas injection part and an outer coil inductively coupled to the inner coil. High-frequency power is supplied from a high-frequency power source to the outer coil. A current flows through the inner coil in a direction to cancel out the magnetic field generated by the current flowing through the outer coil. An induced electric field is generated in the chamber by the magnetic fields generated by the current flowing through the outer coil and the current flowing through the inner coil. The processing gas supplied into the chamber from the gas injection part is plasmaized by the induced electric field generated in the chamber. 【0003】 Japanese Unexamined Patent Application Publication No. 2019-67503 【0004】 The present disclosure provides a technique for controlling the temperature of the central portion of a dielectric window. 【0005】 A plasma processing apparatus according to one exemplary embodiment includes a plasma processing chamber, a substrate support portion disposed in the plasma processing chamber, a dielectric window disposed above the substrate support portion and having an opening penetrating the dielectric window at the central portion thereof, a gas injector extending through the opening of the dielectric window and attached to the central portion of the dielectric window, an antenna disposed above the dielectric window so as to surround the gas injector, an RF power source electrically connected to the antenna, and a heater unit attached to the gas injector so as to heat the dielectric window through the gas injector. 【0006】 According to one exemplary embodiment, a technique for controlling the temperature of the central portion of a dielectric window can be provided. 【0007】Figure 1 is a diagram illustrating an example configuration of an inductively coupled plasma processing apparatus. Figure 2 is a diagram showing an example configuration including the upper part of the plasma processing chamber in a plasma processing apparatus according to one exemplary embodiment. Figure 3 is a perspective view showing an example of a heater unit. Figure 4 is a cross-sectional view showing another example of a heat source. Figure 5 is a diagram showing another example configuration including the upper part of the plasma processing chamber in a plasma processing apparatus according to one exemplary embodiment. Figure 6 is a cross-sectional view showing an enlarged portion of an example of the area around an intake port. Figure 7 is a plan view showing an enlarged portion of an example of the area around an intake port. Figure 8 is a diagram showing an enlarged portion of an example of the area around an exhaust port. Figure 9 is a plan view of a shield box showing an example of the positional relationship between multiple intake ports and multiple exhaust ports. Figure 10 is a flowchart showing an example of a method for controlling the temperature of a dielectric window. 【0008】 Various exemplary embodiments will be described in detail below with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals. 【0009】 [Configuration of Plasma Processing Equipment] The following describes an example of the configuration of a plasma processing system. Figure 1 is a diagram illustrating an example of the configuration of an inductively coupled plasma processing equipment. 【0010】The plasma processing system includes an inductively coupled plasma processing apparatus 1 and a control unit 2. The inductively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply system 30, and an exhaust system 40. The plasma processing chamber 10 includes a dielectric window. The plasma processing apparatus 1 also includes a substrate support unit 11, a gas introduction unit, and an antenna 14. The substrate support unit 11 is located inside the plasma processing chamber 10. The antenna 14 is located on or above the plasma processing chamber 10 (i.e., on or above the dielectric window 101). The plasma processing chamber 10 has a plasma processing space 10s defined by the dielectric window 101, the side walls 102 of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s, and at least one gas outlet for discharging gas from the plasma processing space. The plasma processing chamber 10 is grounded. 【0011】 The substrate support portion 11 includes a main body portion 111 and a ring assembly 112. The main body portion 111 has a central region 111a for supporting the substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 111b of the main body portion 111 surrounds the central region 111a of the main body portion 111 in a plan view. The substrate W is placed on the central region 111a of the main body portion 111, and the ring assembly 112 is placed on the annular region 111b of the main body portion 111 so as to surround the substrate W on the central region 111a of the main body portion 111. Therefore, the central region 111a is also called the substrate support surface for supporting the substrate W, and the annular region 111b is also called the ring support surface for supporting the ring assembly 112. 【0012】In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a bias electrode. The electrostatic chuck 1111 is placed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic chuck electrode 1111b placed within the ceramic member 1111a. The electrostatic chuck electrode 1111b is also called a clamping electrode. In one embodiment, the electrostatic chuck electrode 1111b is electrically connected or coupled to a chuck power supply. The chuck power supply may be a DC power supply or an AC power supply. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Furthermore, other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have an annular region 111b. In this case, the ring assembly 112 may be placed on the annular electrostatic chuck or the annular insulating member, or on both the electrostatic chuck 1111 and the annular insulating member. Also, at least one bias electrode, electrically connected or coupled to the power supply 31 and / or power supply 32 described later, may be placed inside the ceramic member 1111a. Furthermore, the conductive member of the base 1110 and the bias electrode inside the ceramic member 1111a may function as multiple bias electrodes. Also, the electrostatic chuck electrode 1111b may function as a bias electrode. Therefore, the substrate support portion 11 includes at least one bias electrode. 【0013】 The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one covering ring. The edge rings are formed of a conductive or insulating material, and the covering rings are formed of an insulating material. 【0014】The substrate support section 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed within the base 1110, and one or more heaters are arranged within the ceramic member 1111a of the electrostatic chuck 1111. The substrate support section 11 may also include a heat transfer gas supply section configured to supply heat transfer gas to the gap between the back surface of the substrate W and the central region 111a. 【0015】 The gas introduction section is configured to introduce at least one processing gas from the gas supply section 20 into the plasma processing space 10s. In one embodiment, the gas introduction section includes a central gas injector (CGI) 13. The central gas injector 13 is located above the substrate support section 11 and is attached to a central opening formed in the dielectric window 101. The central gas injector 13 has at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas inlet 13c. The processing gas supplied to the gas supply port 13a passes through the gas flow path 13b and is introduced into the plasma processing space 10s from the gas inlet 13c. In addition to or instead of the central gas injector 13, the gas introduction section may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 102. 【0016】 The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one processing gas to the gas inlet from a corresponding gas source 21 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include one or more flow modulation devices that modulate or pulse the flow rate of at least one processing gas. 【0017】 The power supply system 30 includes a power supply 31 that is electrically connected to or coupled to the plasma processing chamber 10. In one embodiment, the power supply 31 is electrically connected to or coupled to the plasma processing chamber 10 via at least one impedance matcher. The impedance matcher may be a mechanically controlled or electronically controlled matcher. The power supply 31 is configured to supply at least one RF (Radio Frequency) signal (RF power) to at least one bias electrode and antenna 14. This generates plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the power supply 31 can function as at least part of a plasma generation unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to at least one bias electrode, a bias potential is generated on the substrate W, and ions in the formed plasma can be drawn into the substrate W. 【0018】 The power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is electrically connected to or coupled to the antenna 14 and is configured to generate a source RF signal (source RF power) to generate plasma in the plasma processing space 10s. In one embodiment, the first RF generation unit 31a is electrically connected to or coupled to the antenna 14 via at least one impedance matcher. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. One or more generated source RF signals are supplied to the antenna 14. 【0019】The second RF generation unit 31b is electrically connected to or coupled to at least one bias electrode and is configured to generate a bias RF signal (bias RF power). In one embodiment, the second RF generation unit 31b is electrically connected to or coupled to at least one bias electrode via at least one impedance matcher. The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one bias electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed. 【0020】 The power supply system 30 may also include a power supply 32 that is electrically connected to or coupled to the plasma processing chamber 10. The power supply 32 includes a voltage generation unit 32a. In one embodiment, the voltage generation unit 32a is electrically connected to or coupled to at least one bias electrode and is configured to generate a voltage signal. The generated voltage signal is applied to at least one bias electrode. 【0021】In various embodiments, the voltage signal may be pulsed. In this case, the voltage generation unit 32a functions as a voltage pulse generation unit configured to generate a sequence of voltage pulses. Thus, the sequence of voltage pulses is applied to at least one bias electrode. In one embodiment, the sequence of voltage pulses has multiple cycles, each cycle including a burst of voltage pulses in a first period and a constant reference voltage in a second period. That is, the burst of voltage pulses is repeated in the sequence of voltage pulses. The absolute value of the voltage level of the voltage pulse is greater than the absolute value of the voltage level of the reference voltage. The voltage pulse may have an arbitrary waveform having a rectangular, trapezoidal, triangular, or a combination thereof, and the arbitrary waveform may change over time. The voltage pulse may have positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one cycle. Note that the voltage generation unit 32a may be provided in addition to the power supply 31, or it may be provided in place of the second RF generation unit 31b. 【0022】 The antenna 14 includes one or more coils. In one embodiment, the antenna 14 may include an outer coil and an inner coil arranged coaxially. In this case, the power supply 31 may be connected to both the outer coil and the inner coil, or to either the outer coil or the inner coil. In the former case, the same RF generation unit may be connected to both the outer coil and the inner coil, or separate RF generation units may be connected to the outer coil and the inner coil separately. 【0023】 The exhaust system 40 may be connected to, for example, a gas outlet 10e located at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure regulating valve regulates the pressure in the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof. 【0024】The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described herein. The control unit 2 may be configured to control the elements of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 is implemented, for example, by a computer 2a. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The functions realized by the processing unit 2a1 described herein may be implemented in a circuit or processing circuit, including a general-purpose processor, an application-specific processor, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (Central Processing Unit), a conventional circuit, and / or a combination thereof, programmed to realize the described functions. The processor is considered to be a circuit or processing circuit, including transistors and other circuits. The processor may be a programmed processor that executes a program stored in the storage unit 2a2. This program may be pre-stored in the storage unit 2a2 or retrieved via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 and executed by the processing unit 2a1. The medium may be various storage media readable by the computer 2a, or it may be a communication line connected to the communication interface 2a3. The storage unit 2a2 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).In this disclosure, circuits, units, and means are hardware programmed to perform or configured to perform the functions described. Such hardware may be any hardware described in this disclosure, or any hardware known to be programmed to perform or execute the functions described. If such hardware is a processor that is considered to be a type of circuit, such circuit, means, or unit is a combination of hardware and software used to constitute such hardware and / or processor. 【0025】 [Example of Plasma Processing Apparatus Configuration Including the Upper Part of the Plasma Processing Chamber] An example of the configuration of a plasma processing apparatus including the upper part of the plasma processing chamber will be described below with reference to Figure 2. Figure 2 is a diagram showing an example of a configuration including the upper part of the plasma processing chamber in a plasma processing apparatus according to one exemplary embodiment. The configuration shown in Figure 2 can be adopted in the plasma processing apparatus 1. 【0026】 In one embodiment, the antenna 14 may include an outer coil 141 and an inner coil 142, as shown in Figure 2. The outer coil 141 and the inner coil 142 are arranged above the dielectric window 101 so as to surround the central gas injection unit (gas injector) 13. The inner coil 142 is arranged between the outer coil 141 and the central gas injection unit 13 so as to surround the central gas injection unit 13. The outer coil 141 is arranged so as to surround the inner coil 142. The outer coil 141 may be electrically connected to the first RF generation unit 31a (RF power supply). In this case, the outer coil 141 is inductively coupled to the inner coil 142. In the plasma processing apparatus 1, when processing a substrate in the plasma processing chamber 10, a source RF signal is output from the power supply 31 to the outer coil 141, and a high-frequency magnetic field can be generated by the outer coil 141 and the inner coil 142. The high-frequency magnetic field that has passed through the dielectric window 101 then excites, for example, the processing gas supplied into the plasma processing chamber 10 from the central gas injection unit 13. 【0027】The dielectric window 101 is positioned above the substrate support portion 11. The dielectric window 101 has an upper surface 101a, a lower surface 101b, and a side surface 101c. The lower surface 101b faces the substrate support portion 11, and the upper surface 101a faces the antenna 14. The lower surface 101b and the upper surface 101a face each other and define the thickness of the dielectric window 101. The side surface 101c connects the upper surface 101a and the lower surface 101b. In the following description, the vertical direction refers to the thickness direction of the dielectric window 101 and may be called the Z direction. The horizontal direction is perpendicular to the vertical direction and may be called the X direction perpendicular to the Z direction, or the Y direction perpendicular to both the Z and X directions. The X and Y directions are perpendicular to each other. The horizontal direction may also be the in-plane direction of the substrate W. 【0028】 The dielectric window 101 further includes a central portion 101d. The central portion 101d is a part of the dielectric window 101 and includes the center of the dielectric window 101. The central portion 101d shares the central axis A1 of the dielectric window 101 with the dielectric window 101. When viewed from the Z direction, the central portion 101d may have a circular shape with a diameter of length T1. The central portion 101d may be located inside the inner coil 142 (towards the central axis A1). The dielectric window 101 further has an opening 101e that penetrates the dielectric window 101 in the central portion 101d. The opening 101e extends in the Z direction from the upper surface 101a to the lower surface 101b. The central axis of the opening 101e may coincide with the central axis A1. When viewed from the Z direction, the outer edge of the opening 101e is inward from the outer edge of the central portion 101d, and the diameter of the opening 101e may be shorter than the length T1. The central gas injection section 13 is attached to the central portion 101d and extends in the Z direction through the opening 101e. 【0029】The plasma processing apparatus 1 may further include a shielding box 15. The shielding box 15 may be formed from a metal such as aluminum. The shielding box 15 includes a top plate 151 and side walls 152. The top plate 151 extends laterally above the dielectric window 101 and the antenna 14. The side walls 152 extend along the Z direction between the top plate 151 and the dielectric window 101 and surround the antenna 14. The shielding box 15 houses the antenna 14 in a shielding space 15s defined by the dielectric window 101, the top plate 151, and the side walls 152. The shielding box 15 can suppress the leakage of RF noise from the shielding space 15s to the outside of the shielding box 15. 【0030】 The top plate 151 has an upper surface 151a and a lower surface 151b. The lower surface 151b faces the shield space 15s and is opposite the antenna 14. The upper surface 151a faces the space outside the shield box 15. The lower surface 151b and the upper surface 151a are opposite each other. The top plate 151 further includes a central portion 151c. The central portion 151c is a part of the top plate 151 that includes the center of the top plate 151. The central portion 151c may share the central axis of the top plate 151 with the top plate 151. The central axis of the top plate 151 may coincide with the central axis A1 of the dielectric window 101. In one embodiment, the top plate 151 may further have an opening 151d in the central portion 151c that penetrates the top plate 151. The opening 151d extends in the Z direction from the upper surface 151a to the lower surface 151b. The central axis of the opening 151d may coincide with the central axis A1. When viewed from the Z direction, the outer edge of the opening 151d may overlap with the outer edge of the opening 101e of the dielectric window 101. The central gas injection section 13 may extend in the Z direction not only through the opening 101e of the dielectric window 101 but also through the opening 151d of the top plate 151. That is, the central gas injection section 13 may extend in the Z direction from the space outside the shield box 15 through the shield space 15s to the plasma processing space 10s. 【0031】[Temperature control mechanism for dielectric window] The plasma processing apparatus 1 includes a temperature control mechanism for the dielectric window 101. The temperature control mechanism for the dielectric window 101 includes a heating mechanism and / or a cooling mechanism for the dielectric window 101. The heating mechanism for the dielectric window 101 will be described below, followed by the cooling mechanism for the dielectric window 101. 【0032】 [Heating mechanism for dielectric window] The plasma processing apparatus 1 further includes a heater unit 41 and a heater control unit 44. The heater unit 41 and the heater control unit 44 are included in the heating mechanism for the dielectric window 101. The heater control unit 44 is configured to control the power supplied to the heater unit 41. 【0033】 The heater unit 41 is attached to the central gas injection section 13 so as to heat the dielectric window 101 via the central gas injection section 13. The heat generated by the heater unit 41 is transferred to the central portion 101d of the dielectric window 101 via the central gas injection section 13. The dielectric window 101 may be made of a ceramic material. The central gas injection section 13 may also be made of a ceramic material. In this case, since the change in thermal conductivity from the central gas injection section 13 to the dielectric window 101 is small, heat can be efficiently transferred from the central gas injection section 13 to the dielectric window 101. The dielectric window 101 may be made of the same ceramic material as the central gas injection section 13. Alternatively, the dielectric window 101 may be made of a different ceramic material than the central gas injection section 13. The dielectric window 101 and the central gas injection section 13 may each be made of at least one material selected from the group consisting of alumina, yttria, and zirconia. 【0034】In one embodiment, the central gas injection section 13 may include a flange section 131 and a main body section 132. The main body section 132 extends in the Z direction through the opening 101e of the dielectric window 101 and the opening 151d of the top plate 151. The main body section 132 may have at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas inlet 13c. The cross-sectional area of ​​the main body section 132 in the X and Y directions may be uniform in the Z direction. When viewed from the Z direction, the outer edge of the main body section 132 may overlap with the outer edge of the opening 101e and the outer edge of the opening 151d. In this case, the side surface of the main body section 132 may contact the inner wall of the opening 101e and the inner wall of the opening 151d. 【0035】 The flange portion 131 protrudes laterally from the main body portion 132. The flange portion 131 may have an annular shape formed to surround the outer circumference of the main body portion 132. When viewed from the Z direction, the outer edge of the flange portion 131 may overlap with the outer edge of the central portion 101d of the dielectric window 101. In this case, the diameter of the flange portion 131 may be a length T1. The flange portion 131 may have an upper surface 131a and a lower surface 131b. The lower surface 131b and the upper surface 131a face each other. The lower surface 131b is, for example, positioned on the upper surface 101a of the dielectric window 101 in the central portion 101d of the dielectric window 101. The lower surface 131b of the flange portion 131 may be in contact with the upper surface 101a of the dielectric window 101 in the central portion 101d. 【0036】The heater unit 41 may be positioned on the upper surface 131a of the flange portion 131. The heater unit 41 may be in contact with the upper surface 131a of the flange portion 131. In this case, the heater unit 41 can heat the dielectric window 101 via the flange portion 131. Also, in this case, since the heater unit 41 is not formed inside the dielectric window 101 but is positioned above the dielectric window 101, the influence of the heater unit 41 on the induced magnetic field generated in the plasma processing chamber 10 via the dielectric window 101 by the antenna 14 can be suppressed. Therefore, the influence on plasma ignition and plasma density distribution in the plasma processing chamber 10 can be suppressed. Also, in this case, since the heater unit 41 is positioned on the flange portion 131 of the central gas injection portion 13 which is positioned inside the inner coil 142, it is positioned inside the inner coil 142. Therefore, the influence of RF noise on the heater unit 41 can be suppressed. Thus, the heater unit 41 can be stably controlled. 【0037】 In one embodiment, the heater unit 41 may have an annular shape or surround the outer circumference of the main body 132. The heater unit 41 may not be in contact with the main body 132. In the example of Figure 2, there is a gap between the side surface of the main body 132 and the heater unit 41. This makes it easier for the heat generated by the heater unit 41 to be transferred to the flange 131 than to the main body 132. 【0038】 Figure 3 is a perspective view showing an example of a heater unit. As shown in Figure 3, the heater unit 41 may include an annular base material 411 and a heating source 412. The annular base material 411 has a substantially ring shape. The annular base material 411 has heat conductivity and is positioned on the upper surface 131a of the flange portion 131 so as to surround the outer circumference of the main body portion 132. The annular base material 411 may be in contact with the upper surface 131a. The annular base material 411 may be formed from a metal such as aluminum that has high heat conductivity. 【0039】In one embodiment, the annular substrate 411 includes a slit SL, as shown in Figure 3. The slit SL is formed in a portion of the annular substrate 411 in the circumferential direction. The slit SL makes it easier for the high-frequency magnetic field generated by the outer coil 141 and the inner coil 142 to pass through the dielectric window 101, thereby facilitating the generation of a stable plasma in the plasma processing chamber 10. In contrast to the example in Figure 3, the annular substrate 411 may have a completely annular shape without including the slit SL. 【0040】 The heating source 412 is positioned to heat the annular base material 411. With this heater unit 41 including the annular base material 411 and the heating source 412, it is possible to achieve miniaturization of the heater unit 41 while ensuring a large contact area of ​​the heater unit 41 with the upper surface 131a of the flange portion 131. 【0041】 The heating source 412 may be located inside the annular substrate 411. The heating source 412 may be in direct contact with the annular substrate 411 inside the annular substrate 411. Alternatively, the heating source 412 may be in thermal contact with the annular substrate 411 inside the annular substrate 411 via an intermediate member. The intermediate member may be a metallic member with high heat conductivity, such as aluminum, for example, a metal plate. 【0042】 In one embodiment, the heating source 412 may be formed from aluminum nitride. In one example, the heating source 412 may be an aluminum nitride heater. The aluminum nitride heater may be made by integrally sintering a substrate and a heating element (resistive heating element) formed from aluminum nitride. The aluminum nitride heater can constitute a small heating source 412. In another example, the heating source 412 may be a sheathed heater. The sheathed heater includes a heating element (e.g., an electric heating wire such as nichrome wire) and a sheath, which is a metal pipe that covers the heating element. The sheathed heater has high durability because the heating element is covered by the sheath. 【0043】FIG. 4 is a cross-sectional view showing another example of the heating source. In another example, the heating source 412 may be disposed on the annular base material 411. For example, the heating source 412 may be disposed on the upper surface of the annular base material 411. The heating source 412 is, for example, a thermal spraying heater. In this case, the heating source 412 may be composed only of a heating element. The heating source 412 may be directly formed on the upper surface of the annular base material 411 by thermal spraying. In thermal spraying, since materials such as metal or ceramic can be laminated as thin layers, the heating source 412 may exhibit a layered structure. 【0044】 In any of the examples, the heating element of the heating source 412 is electrically connected to the heater control unit 44 via the electric wire WR. The heating element of the heating source 412 generates heat according to the electric power supplied from the heater control unit 44 via the electric wire WR. The electric wire WR may be covered with an insulating coating tube. Also, as shown in FIG. 3, the electric wire WR may be covered with the case C. The lower end portion of the case C may be disposed in the annular base material 411 together with the heating source 412. 【0045】As shown in Figure 3, the heater unit 41 may further include a temperature sensor 413 and a thermostat 414. The heating source 412, temperature sensor 413, and thermostat 414 may be arranged at equal intervals along the circumferential direction of the annular substrate 411. Each of the heating source 412, temperature sensor 413, and thermostat 414 is housed, for example, inside the annular substrate 411. Each of the heating source 412, temperature sensor 413, and thermostat 414 may be in direct contact with the annular substrate 411 inside the annular substrate 411, or indirectly contact with the annular substrate 411 inside the annular substrate 411. For example, each of the heating source 412, temperature sensor 413, and thermostat 414 may be indirectly in contact with the annular substrate 411 via a member such as a metal plate. Each of the temperature sensor 413 and the thermostat 414 may be electrically connected to the heater control unit 44 via another wire WR. The wire WR may be covered with an insulating sheathing tube. The wire WR connected to each of the temperature sensor 413 and the thermostat 414 may also be protected by another insulating case C. The lower end of the other case C may be located within the annular base material 411. 【0046】The temperature sensor 413 is configured to measure the temperature of the heater unit 41. In the example of FIG. 2, a flange portion 131 exists between the temperature sensor 413 and the upper surface 101a of the dielectric window 101. Since the temperature sensor 413 is not in direct contact with the dielectric window 101, the influence of the temperature sensor 413 on the induced magnetic field is suppressed, and plasma can be stably generated in the plasma processing chamber 10. The temperature sensor 413 is, for example, a Pt sensor (platinum temperature sensor). The temperature sensor 413 outputs the measured value of the temperature of the heater unit 41 to the heater control unit 44. As will be described later, the measured value of the temperature of the heater unit 41 is used in the heater control unit 44 to control the power supplied to the heater unit 41. Note that the temperature sensor 413 may measure the temperature of the dielectric window 101 (for example, the central portion 101d) in a non-contact manner. The temperature sensor 413 may be disposed in the annular base material 411 as described above, or may be disposed above the annular base material 411 and the dielectric window 101. 【0047】 The thermostat 414 is used to ensure the normal operation of the heater unit 41. The thermostat 414, for example, compares the measured value of the temperature of the heater unit 41 measured by the temperature sensor 413 with a temperature threshold value, and outputs a detection signal to the heater control unit 44 when the measured value exceeds the temperature threshold value. The heater control unit 44 may stop supplying power to the heater unit 41 when a detection signal is input from the thermostat 414. The temperature threshold value may be the maximum temperature of the heating source included in the heater unit 41 or the rated temperature. 【0048】 In one embodiment, as shown in FIG. 2, the plasma processing chamber 10 may further include a side wall heater unit 42. The plasma processing chamber 10 includes the above-described side wall 102 extending in the vertical direction. The side wall heater unit 42 is attached to the side wall 102 and is configured to heat the outer peripheral portion of the dielectric window 101. 【0049】In one embodiment, the side wall heater unit 42 may be part of the side wall 102. In one example, the side wall heater unit 42 extends along the lower surface of the outer periphery of the dielectric window 101 and supports the dielectric window 101. In this case, the side wall 102 includes a side wall body that extends downward from the side wall heater unit 42. The side wall heater unit 42 is positioned between the side wall body and the outer periphery of the dielectric window 101. The side wall heater unit 42 may be positioned at any location as long as it can heat the side wall 102 and the outer periphery of the dielectric window 101. 【0050】 In one embodiment, the side wall heater unit 42 may include a ring member 421 and a heating source 422. The ring member 421 is formed from a metal such as aluminum that has high heat conductivity. The ring member 421 has a substantially ring shape. The ring member 421 may be positioned between the side wall body of the side wall 102 and the outer periphery of the dielectric window 101. The heating source 422 is configured to heat the ring member 421. The heating source 422 may be positioned inside the ring member 421. The heating source 422 may be formed from aluminum nitride, like the heating source 412, may be a sheathed heater, or may consist only of a heating element. 【0051】 The plasma processing apparatus 1 may further include a temperature sensor 43. The temperature sensor 43 is configured to measure the temperature of the side wall heater unit 42. The temperature sensor 43 is located, for example, inside the side wall heater unit 42 (for example, inside the ring member 421) or below the side wall heater unit 42 (for example, below the ring member 421). The temperature sensor 43 is, for example, a Pt sensor (platinum temperature sensor). The temperature sensor 43 outputs the measured temperature of the side wall heater unit 42 to the heater control unit 44. The temperature sensor 43 may also measure the temperature of the dielectric window 101 (for example, the outer periphery of the dielectric window 101) non-contact. The temperature sensor 43 may be located inside the ring member 421 as described above, or it may be located above the dielectric window 101. 【0052】[Configuration of Heater Control Unit] The heater control unit 44 may be configured to control at least one of the power supplied to the heater unit 41 and the power supplied to the side wall heater unit 42 based on the output of the temperature sensor. For example, the heater control unit 44 is configured to control the power supplied to the heater unit 41 based on the output of the temperature sensor 413. The output of the temperature sensor 413 includes the temperature measurement obtained by the temperature sensor 413. As described above, the temperature measurement obtained by the temperature sensor 413 is the temperature measurement of the heater unit 41 or the dielectric window 101 (e.g., the central portion 101d). In one embodiment, the heater control unit 44 may be configured to control the power supplied to the heater unit 41 based on the outputs of the temperature sensor 103 and the temperature sensor 413, which will be described later. Furthermore, the heater control unit 44 may be configured to control the power supplied to the side wall heater unit 42 based on the output of the temperature sensor 43. The output of the temperature sensor 43 includes the temperature measurement obtained by the temperature sensor 43. As described above, the temperature measurement obtained by the temperature sensor 43 is the temperature measurement of the side wall heater unit 42 or the dielectric window 101 (for example, the outer periphery of the dielectric window 101). In one embodiment, the heater control unit 44 may be configured to control the power supplied to the side wall heater unit 42 based on the outputs of the temperature sensor 103 and temperature sensor 43, which will be described later. 【0053】The heater control unit 44 may be configured to control the power supplied to the heater unit 41 so that the temperature measurement obtained by the temperature sensor 413 converges to a first target temperature. The heater control unit 44 controls the power supplied to the heater unit 41 by, for example, PID control. Similarly, the heater control unit 44 may be configured to control the power supplied to the side wall heater unit 42 so that the temperature measurement obtained by the temperature sensor 43 converges to a second target temperature. The heater control unit 44 controls the power supplied to the side wall heater unit 42 by, for example, PID control. As an example, the first target temperature and the second target temperature may be 100°C or higher, or 120°C or higher. The first target temperature and the second target temperature may be 200°C or lower, or 150°C or lower. 【0054】 The plasma processing apparatus 1 further includes an RF filter 45a connected between the heater unit 41 and the heater control unit 44. The plasma processing apparatus 1 may also further include an RF filter 45b connected between the side wall heater unit 42 and the heater control unit 44. The RF filters 45a and 45b are electrical filters that block or attenuate RF noise directed toward the heater control unit 44. The RF filters 45a and 45b can suppress the influence of RF noise on the operation of the heater unit 41 and the side wall heater unit 42. 【0055】According to the heating mechanism of the dielectric window 101 described above, the heating capacity of the central portion 101d of the dielectric window 101 can be increased by the heater unit 41. Furthermore, since the heater unit 41 heats the central portion 101d of the dielectric window 101 and the side wall heater unit 42 heats the outer periphery of the dielectric window 101, the entire dielectric window 101 can be heated uniformly. Therefore, when pre-coating is performed on the plasma processing chamber 10, the surface inside the plasma processing chamber 10 can be uniformly coated. In addition, it may be easier to control the generation of particles inside the plasma processing chamber 10. Furthermore, the in-plane uniformity of the plasma processing on the substrate W inside the plasma processing chamber 10 can be improved. Furthermore, if the plasma processing is plasma etching, the selectivity ratio may be improved. Furthermore, the stability of the temperature environment for plasma processing inside the plasma processing chamber 10 can be improved. In addition, the heating unit 41 and the side wall heater unit 42 can increase the heating rate of the dielectric window 101. Furthermore, the high heating rate of the dielectric window 101 can shorten the time required to bring the temperature of the dielectric window 101 to the target temperature before plasma processing. 【0056】 [Cooling Mechanism for Dielectric Window] The following refers to Figure 5. Figure 5 shows another example of the configuration including the upper part of the plasma processing chamber in a plasma processing apparatus according to one exemplary embodiment. The configuration shown in Figure 5 differs from the configuration shown in Figure 2 in that it includes a configuration for cooling the dielectric window 101. In Figure 5, some components such as the antenna 14 and RF filters 45a, 45b are not shown. The plasma processing apparatus 1 may include the cooling mechanism for the dielectric window 101 shown in Figure 5. The cooling mechanism for the dielectric window 101 is configured to cool the dielectric window 101. The cooling mechanism for the dielectric window 101 may be configured, for example, to control the temperature of the dielectric window 101 so that the temperature of the dielectric window 101 does not become excessively high during plasma processing. 【0057】The cooling mechanism for the dielectric window 101 includes at least one intake port 151e and at least one exhaust port 152a formed in the shield box 15, as well as at least one fan 16. The cooling mechanism for the dielectric window 101 may further include at least one first perforated plate 153. The cooling mechanism for the dielectric window 101 may further include at least one second perforated plate 161. The cooling mechanism for the dielectric window 101 may further include at least one louver 157. In the cooling mechanism for the dielectric window 101, the number of each of the intake port 151e, exhaust port 152a, fan 16, first perforated plate 153, second perforated plate 161, and louver 157 may be one. Alternatively, in the cooling mechanism for the dielectric window 101, the number of each of the intake port 151e, exhaust port 152a, fan 16, first perforated plate 153, second perforated plate 161, and louver 157 may be multiple. The cooling mechanism of the dielectric window 101 will be described below, using as an example the case where there are multiple intake ports 151e, exhaust ports 152a, fans 16, first perforated plates 153, second perforated plates 161, and louvers 157. 【0058】 Multiple air intake ports 151e are formed in the top plate 151. The multiple air intake ports 151e extend along the Z direction from the upper surface 151a to the lower surface 151b and penetrate the top plate 151. The center of each of the multiple air intake ports 151e may be located closer to the central gas injection section 13 than to the side wall 152 in the lateral direction. Multiple exhaust ports 152a are formed in the side wall 152. The side wall 152 has an inner surface 152b facing the shield space 15s and an outer surface 152c located on the opposite side of the inner surface 152b and facing the outside of the shield box 15. The multiple exhaust ports 152a extend along the lateral direction from the inner surface 152b to the outer surface 152c and penetrate the side wall 152. 【0059】Multiple fans 16 are located outside the shield box 15 and are mounted on the top plate 151. Each of the multiple fans 16 is positioned on one of the multiple air intake ports 151e. The multiple fans 16 are configured to take in air (gas) from outside the shield box 15 and supply it to the shield space 15s through the multiple air intake ports 151e. 【0060】 Hereinafter, Figures 6 and 7 will be referenced in conjunction with Figure 5. Figure 6 is a cross-sectional view showing an enlarged portion of an example of the area around an air intake. Figure 7 is a plan view showing an enlarged portion of an example of the area around an air intake. The plurality of first perforated plates 153 are formed from a conductive material, such as a metal like aluminum. The plurality of first perforated plates 153 are part of the shield box 15. The plurality of first perforated plates 153 are attached to the top plate 151. The plurality of first perforated plates 153 may be positioned between their respective fans 16 and their respective air intakes 151e. The outer edges of the plurality of first perforated plates 153 may be positioned on the upper surface 151a of the top plate 151. The outer edges of the plurality of first perforated plates 153 may be in contact with the upper surface 151a. 【0061】 Each of the multiple first punching plates 153 includes a first punching plate body 155 and multiple first through holes 156. The multiple first through holes 156 penetrate the first punching plate body 155 and communicate with the corresponding air intake port 151e. The multiple first through holes 156 may be formed in the first punching plate body 155 within a region R1 that overlaps with the corresponding air intake port 151e. The multiple first through holes 156 may be arranged regularly within region R1. The multiple first through holes 156 may be arranged in a grid pattern within region R1. The opening ratio of each first punching plate 153 within region R1 may be 50% or more, 70% or more, or 90% or more. Note that the opening ratio of each first punching plate 153 within region R1 is the proportion of region R1 occupied by the multiple first through holes 156. 【0062】As shown in Figures 5 and 6, the multiple louvers 157 are attached to the top plate 151 below the corresponding first perforated plate 153, and each louver 157 is attached to the top plate 151 so as to overlap the corresponding air intake 151e. Each of the multiple louvers 157 may include a louver body 158 and multiple through holes 159. The multiple through holes 159 pass through the louver body 158. The multiple through holes 159 are formed to create an airflow toward the upper surface 101a of the dielectric window 101. 【0063】 Multiple first perforated plates 153 may be positioned between their respective fans 16 and their respective louvers 157. Multiple louvers 157 may be positioned within their respective air intakes 151e. The inner wall surface of the top plate 151 defining the air intake 151e may include a stepped surface, and the side surface of the louver body 158 may have a stepped surface positioned on the stepped surface of the inner wall surface of the air intake 151e. 【0064】 The multiple through-holes 159 may extend in a direction inclined with respect to the Z direction to form an airflow toward the upper surface 101a of the dielectric window 101. The multiple through-holes 159 are inclined inward with respect to the Z direction, for example, so that they approach the central portion 101d as they move from their upper end towards their lower end. The size of each through-hole 159 may be larger than the size of each first through-hole 156. The size of each through-hole 159 may be about 10 times the size of each first through-hole 156. The opening ratio of the louvers 157 in the region overlapping the corresponding air intake port 151e may be 60% or more, 70% or more, or 90% or more. The opening ratio of the louvers 157 is the proportion of the region within the louvers 157 that overlaps the corresponding air intake port 151e that is occupied by the multiple through-holes 159. 【0065】Hereafter, refer to Figure 8 along with Figure 5. Figure 8 is a magnified view of an example of the area around an exhaust port. The plurality of second perforated plates 161 are made of a conductive material, such as a metal like aluminum. The plurality of second perforated plates 161 are part of the shield box 15. The plurality of second perforated plates 161 are attached to the side wall 152. Each of the plurality of second perforated plates 161 is arranged to overlap with the plurality of exhaust ports 152a in the lateral direction (for example, radially with respect to the central axis A1). The plurality of second perforated plates 161 may be located outside the shield box 15, or may be arranged along the outer surface 152c of the side wall 152. The outer edges of the plurality of second perforated plates 161 may extend along the outer surface 152c, or may be in contact with the outer surface 152c. 【0066】 Each of the multiple second punching plates 161 includes a second punching plate body 162 and multiple second through holes 163. The multiple second through holes 163 penetrate the second punching plate body 162 and communicate with the corresponding exhaust port 152a. The multiple second through holes 163 may be formed in a region R2 (152a) of the second punching plate body 162 that overlaps with the corresponding exhaust port 152a. The multiple second through holes 163 may be arranged regularly within region R2. The multiple second through holes 163 may be arranged in a grid pattern. The opening ratio of each second punching plate 161 in region R2 may be 50% or more, 70% or more, or 90% or more. Note that the opening ratio of each second punching plate 161 in region R2 is the proportion of region R2 occupied by the multiple second through holes 163. 【0067】Refer to Figure 9 below. Figure 9 is a plan view of a shield box showing an example of the positional relationship between multiple intake ports and multiple exhaust ports. In one embodiment, the multiple intake ports 151e may be arranged symmetrically with respect to a vertical plane B1 that includes the central axis A1 of the dielectric window 101. In the example of Figure 9, the vertical plane B1 is perpendicular to the X direction and parallel to the Y direction. The multiple intake ports 151e may be formed in locations that are rotationally symmetrical with respect to the central axis A1. The multiple exhaust ports 152a may be arranged at equal intervals with respect to the central axis A1 of the dielectric window 101. The multiple exhaust ports 152a may be formed in locations that are rotationally symmetrical with respect to the central axis A1. 【0068】 In one embodiment, the angular range around the central axis A1 in which each of the multiple intake ports 151e is located may be between two angular ranges in which two corresponding exhaust ports 152a adjacent to each other along the circumferential direction are located. In the example of Figure 9, in the region on one side (negative X direction) and the region on the other side (positive X direction) with respect to the vertical plane B1, the angular range in which each of the multiple intake ports 151e is located and the angular range in which each of the multiple exhaust ports 152a is located are alternately located around the central axis A1. With this arrangement, the path from which the air AR taken into the shield space 15s from the multiple intake ports 151e is exhausted from the multiple exhaust ports 152a can be lengthened. As a result, the cooling performance of the dielectric window 101 is improved. Note that the number of intake ports 151e and the number of exhaust ports 152a are not limited to the example of Figure 9, and may be any number of two or more. 【0069】As shown in Figure 5, the plasma processing apparatus 1 may further include a fan control unit 46 for controlling the airflow of a plurality of fans 16 and a temperature sensor 103 for measuring the temperature of the dielectric window 101. The fan control unit 46 may control the airflow of the plurality of fans 16 so as to converge the measured temperature of the dielectric window 101 obtained by the temperature sensor 103 to a third target temperature. The temperature sensor 103 is, for example, located on the top plate 151 of the shield box 15. The temperature sensor 103 is, for example, a radiation thermometer. In this case, the temperature sensor 103 may detect infrared radiation emitted from the dielectric window 101. Also, below the temperature sensor 103, a transparent portion 103a may be formed in the top plate 151. The transparent portion 103a may be formed to penetrate the top plate 151, for example. The transparent portion 103a may be a through hole or a member that transmits infrared radiation. Infrared radiation emitted from the dielectric window 101 can be detected by the temperature sensor 103 through the transparent portion 103a. The temperature sensor 103 outputs the measured temperature of the dielectric window 101 to the fan control unit 46. The fan control unit 46 may control the airflow of the multiple fans 16, for example, by PID control. In one embodiment, the fan control unit 46 may control the airflow of the multiple fans 16 based on the output of the temperature sensor 103 and the output of at least one of the temperature sensors 413 and 43. 【0070】 An example of the air AR flow formed to cool the dielectric window 101 by the cooling mechanism described above will be explained with reference to Figure 5. Air AR taken in from the multiple fans 16 flows through the multiple first punching plates 153 and the multiple louvers 157 into the shield space 15s. The air AR that has flowed into the shield space 15s is exhausted to the outside of the shield box 15 through the multiple exhaust ports 152a and the multiple second punching plates 161. The air AR taken in from the multiple fans 16 into the shield space 15s cools the dielectric window 101 before being exhausted from the multiple exhaust ports 152a. Therefore, the temperature of the dielectric window 101 can be controlled. 【0071】In one embodiment, the direction of the air AR flow is adjusted by a plurality of louvers 157 to be inclined with respect to the Z direction. This allows air AR to be supplied to a part of the upper surface 101a of the dielectric window 101 that is particularly prone to becoming hot (for example, the central part 101d), and the part that is prone to becoming hot can be efficiently cooled. Furthermore, the flow of air AR formed by the plurality of louvers 157 promotes the generation of turbulence in the shield space 15s, so that the entire surface of the dielectric window 101 can be efficiently cooled. In addition, air AR is taken in from a plurality of fans 16 and exhausted from a plurality of exhaust ports 152a, so that a plurality of air AR flow paths are formed in the shield space 15s, and the dielectric window 101 can be cooled more efficiently. In this way, the dielectric window 101 is cooled during plasma processing and controlled so that the temperature of the dielectric window 101 does not become excessively hot during plasma processing. 【0072】 Furthermore, the formation of air AR flow through multiple intake ports 151e, multiple exhaust ports 152a, and louvers 157 results in low pressure loss, which can improve conductance within the shield space 15s. Therefore, the cooling mechanism of the dielectric window 101 allows for improved cooling performance of the dielectric window 101 due to the large airflow of air AR within the shield space 15s. Consequently, high throughput can be achieved. In addition, the temperature of the dielectric window 101 can be stably controlled by the control of the fan control unit 46. Furthermore, the temperature of the entire dielectric window 101 can be uniformly controlled. Consequently, when pre-coating is performed on the plasma processing chamber 10, the surface inside the plasma processing chamber 10 can be uniformly coated. Furthermore, control of particle generation inside the plasma processing chamber 10 can be made easier. Furthermore, the in-plane uniformity of plasma processing on the substrate W inside the plasma processing chamber 10 can be improved. Furthermore, when the plasma processing is plasma etching, the selectivity ratio can be improved. Furthermore, the stability of the temperature environment for plasma processing inside the plasma processing chamber 10 can be improved. 【0073】Furthermore, for example, the size of each of the multiple first through-holes 156 in the first punching plate 153 and each of the multiple second through-holes 163 in the second punching plate 161 is set to a size that can suppress RF noise leakage. Since the first punching plate 153 and the second punching plate 161 overlap with the intake port 151e and exhaust port 152a, RF noise leakage from the shielding space 15s to the outside of the shielding box 15 can be suppressed. 【0074】 [Temperature Control Method for Dielectric Window] The following describes a method for controlling the temperature of the dielectric window 101 in the plasma processing apparatus 1 described above. Figure 10 is a flowchart showing an example of a method for controlling the temperature of the dielectric window. The method shown in Figure 10 may include steps ST1 to ST12. Steps ST1 to ST12 may be performed in order. Steps ST1 and ST2 may be performed simultaneously, or step ST2 may be performed first. Furthermore, the series of steps ST3 to ST5, the series of steps ST6 to ST8, and the series of steps ST9 to ST11 may be performed simultaneously, or any of the series of steps may be performed first. The method shown in Figure 10 may be started at the timing when the plasma processing apparatus 1 is driven. The method shown in Figure 10 can be performed both when plasma is not being generated in the plasma processing chamber 10 (idling state) and when plasma is being generated (plasma generation state). 【0075】First, the heater control unit 44 obtains a temperature measurement of the heater unit 41 from the temperature sensor 413 (step ST1) and obtains a temperature measurement of the side wall heater unit 42 from the temperature sensor 43 (step ST2). Next, the heater control unit 44 determines whether the temperature measurement of the heater unit 41 exceeds the first target temperature (step ST3). If the temperature measurement exceeds the first target temperature (step ST3: YES), the heater control unit 44 may reduce the power supplied to the heater unit 41 (step ST4). Alternatively, if the temperature measurement is below the first target temperature (step ST3: NO), the heater control unit 44 may increase the power supplied to the heater unit 41 (step ST5). Next, the heater control unit 44 determines whether the temperature measurement of the side wall heater unit 42 exceeds the second target temperature (step ST6). If the measured value exceeds the second target temperature (step ST6: YES), the heater control unit 44 may reduce the power supplied to the side wall heater unit 42 (step ST7). Alternatively, if the measured value falls below the second target temperature (step ST6: NO), the heater control unit 44 may increase the power supplied to the side wall heater unit 42 (step ST8). 【0076】 Next, the fan control unit 46 determines whether the measured temperature of the dielectric window 101 exceeds the third target temperature (step ST9). For example, the fan control unit 46 obtains the measured temperature of the dielectric window 101 from a temperature sensor 103 placed on the top plate 151 of the shield box 15. If the measured temperature exceeds the third target temperature (step ST9: YES), the fan control unit 46 may increase the electrical energy supplied to the multiple fans 16 to strengthen the airflow of the multiple fans 16 (step ST10). Alternatively, if the measured temperature falls below the third target temperature (step ST9: NO), the fan control unit 46 may decrease the electrical energy supplied to the multiple fans 16 to weaken the airflow of the multiple fans 16 (step ST11). Steps ST1 to ST11 above may be repeated while the plasma processing apparatus 1 is running (step ST12). 【0077】Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments. 【0078】 Herein, various exemplary embodiments included in this disclosure are described in [E1] to [E16] below. 【0079】[E1] A plasma processing apparatus comprising: a plasma processing chamber; a substrate support portion disposed within the plasma processing chamber; a dielectric window disposed above the substrate support portion, the dielectric window having an opening in the central portion of the dielectric window that penetrates the dielectric window; a gas injector extending through the opening of the dielectric window and attached to the central portion of the dielectric window; an antenna disposed above the dielectric window so as to surround the gas injector; an RF power supply electrically connected to the antenna; and a heater unit attached to the gas injector to heat the dielectric window via the gas injector. [E2] The plasma processing apparatus according to [E1], wherein the dielectric window is formed from a ceramic material, and the gas injector is formed from a ceramic material. [E3] The plasma apparatus according to [E1] or [E2], wherein the gas injector comprises a main body portion extending vertically through the opening, and a flange portion having an upper surface and a lower surface, and projecting laterally from the main body portion, the lower surface of which is positioned on the upper surface of the dielectric window, and the heater unit is positioned on the upper surface of the flange portion. [E4] The plasma apparatus according to [E3], wherein the lower surface of the flange portion is in contact with the upper surface of the dielectric window in the central portion of the dielectric window, and the heater unit is in contact with the upper surface of the flange portion. [E5] The plasma apparatus according to [E4], wherein the heater unit comprises an annular substrate having heat transfer properties and positioned on the upper surface of the flange portion so as to surround the outer circumference of the main body portion, and a heating source positioned to heat the annular substrate. [E6] The plasma apparatus according to [E5], wherein the heating source is positioned within the annular substrate. [E7] The plasma apparatus according to [E6], wherein the heating source is formed of aluminum nitride. [E8] The plasma apparatus according to [E5], wherein the heating source is a thermal spray heater disposed on the annular substrate. [E9] The plasma apparatus according to any one of [E5] to [E7], wherein the heating source is a sheath heater.[E10] The plasma processing apparatus according to any one of [E1] to [E9], wherein the plasma processing chamber comprises a side wall extending in the longitudinal direction and a side wall heater unit attached to the side wall and configured to heat the outer periphery of the dielectric window. [E11] The plasma processing apparatus according to [E10], further comprising a temperature sensor configured to measure the temperature of the dielectric window and a heater control unit configured to control at least one of the power supplied to the heater unit and the power supplied to the side wall heater unit based on the output of the temperature sensor. [E12] The plasma processing apparatus according to [E11], wherein the temperature sensor is not in contact with the dielectric window. [E13] The plasma processing apparatus according to any one of [E1] to [E12], further comprising a temperature sensor configured to measure the temperature of the heater unit and a heater control unit configured to control the power supplied to the heater unit based on the output of the temperature sensor. [E14] The plasma apparatus according to [E13], wherein the heater control unit is configured to control the power supplied to the heater unit to converge the measured temperature of the heater unit to a target temperature. [E15] The plasma apparatus according to any one of [E11] to [E14], further comprising an RF filter connected between the heater unit and the heater control unit. [E16] The plasma apparatus according to any one of [E1] to [E15], wherein the antenna includes an outer coil and an inner coil disposed between the outer coil and the gas injector and inductively coupled to the outer coil, and the RF power supply is electrically connected to the outer coil. 【0080】 1...Plasma processing apparatus, 10...Plasma processing chamber, 11...Substrate support section, 13...Central gas injection section (gas injector), 14...Antenna, 31...Power supply (RF power supply), 41...Heater unit, 101...Dielectric window, 101d...Central section, 101e...Opening.

Claims

1. A plasma processing apparatus comprising: a plasma processing chamber; a substrate support portion disposed within the plasma processing chamber; a dielectric window disposed above the substrate support portion, the dielectric window having an opening that penetrates the dielectric window in the central portion thereof; a gas injector extending through the opening of the dielectric window and attached to the central portion thereof; an antenna disposed above the dielectric window so as to surround the gas injector; an RF power supply electrically connected to the antenna; and a heater unit attached to the gas injector so as to heat the dielectric window via the gas injector.

2. The plasma processing apparatus according to claim 1, wherein the dielectric window is formed from a ceramic material, and the gas injector is formed from a ceramic material.

3. The plasma processing apparatus according to claim 1 or 2, wherein the gas injector includes a main body portion extending vertically through the opening, and a flange portion having an upper surface and a lower surface, the lower surface of which is positioned above the upper surface of the dielectric window, and the heater unit is positioned above the upper surface of the flange portion.

4. The lower surface of the flange portion is in contact with the upper surface of the dielectric window in the central portion of the dielectric window, and the heater unit is in contact with the upper surface of the flange portion, as described in claim 3.

5. The plasma processing apparatus according to claim 4, wherein the heater unit includes an annular substrate having heat transfer properties and disposed on the upper surface of the flange portion so as to surround the outer circumference of the main body portion, and a heating source disposed to heat the annular substrate portion.

6. The plasma processing apparatus according to claim 5, wherein the heating source is disposed within the annular substrate.

7. The plasma processing apparatus according to claim 6, wherein the heating source is formed from aluminum nitride.

8. The plasma processing apparatus according to claim 5, wherein the heating source is a thermal spray heater disposed on the annular substrate.

9. The plasma processing apparatus according to claim 5, wherein the heating source is a sheathed heater.

10. The plasma processing apparatus according to claim 1 or 2, wherein the plasma processing chamber includes a side wall extending in the longitudinal direction and a side wall heater unit attached to the side wall and configured to heat the outer periphery of the dielectric window.

11. The plasma processing apparatus according to claim 10, further comprising: a temperature sensor configured to measure the temperature of the dielectric window; and a heater control unit configured to control at least one of the power supplied to the heater unit and the power supplied to the side wall heater unit based on the output of the temperature sensor.

12. The plasma processing apparatus according to claim 11, wherein the temperature sensor is not in contact with the dielectric window.

13. The plasma processing apparatus according to claim 1, further comprising: a temperature sensor configured to measure the temperature of the heater unit; and a heater control unit configured to control the power supplied to the heater unit based on the output of the temperature sensor.

14. The plasma processing apparatus according to claim 13, wherein the heater control unit is configured to control the power supplied to the heater unit to converge the measured temperature of the heater unit to a target temperature.

15. The plasma processing apparatus according to claim 11, further comprising an RF filter connected between the heater unit and the heater control unit.

16. The plasma apparatus according to claim 1 or 2, wherein the antenna includes an outer coil and an inner coil disposed between the outer coil and the gas injector and inductively coupled to the outer coil, and the RF power supply is electrically connected to the outer coil.

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