Temperature regulating device and plasma processing device

Abstract

This temperature regulating device for regulating the temperature of a substrate includes a stage, a storage tank, and a heat transfer member. The stage supports the substrate. The storage tank is provided below the stage and stores a heat transfer fluid. The heat transfer member is connected to the lower surface of the stage, is made of metal, and is at least partly immersed in the heat transfer fluid in the storage tank. Furthermore, the storage tank includes a tank main body, a supply port, a discharge port, and an agitating unit. The supply port supplies the heat transfer fluid into the tank main body. The discharge port discharges the heat transfer fluid from the tank main body. The agitating unit is configured to agitate the heat transfer fluid in the tank main body.

Description

Temperature control device and plasma processing device

[0001] Various aspects and embodiments of the present disclosure relate to a temperature adjustment device and a plasma processing device.

[0002] Patent Document 1 listed below discloses that "a flow path 20 is formed inside the substrate 2a. A refrigerant inlet pipe 21a is connected to one end of the flow path 20. A refrigerant outlet pipe 21b is connected to the other end of the flow path 20. The refrigerant inlet pipe 21a and the refrigerant outlet pipe 21b are connected to a chiller unit (not shown). The flow path 20 is located below the wafer 8 and functions to absorb heat from the wafer 8. The plasma processing apparatus 100 is configured to be able to control the mounting table 2 to a predetermined temperature by circulating a refrigerant, such as cooling water or an organic solvent such as Galden, through the flow path 20 from the chiller unit via the refrigerant inlet pipe 21a and the refrigerant outlet pipe 21b."

[0003] Japanese Patent Application Laid-Open No. 2021-22587

[0004] The present disclosure provides a temperature adjustment device and a plasma processing device that can more efficiently adjust the temperature of a stage that supports a substrate.

[0005] One aspect of the present disclosure is a temperature adjustment device for adjusting the temperature of a substrate, the temperature adjustment device comprising a stage, a storage tank, and a heat transfer member. The stage supports the substrate. The storage tank is provided below the stage and stores a heat transfer fluid. The heat transfer member is connected to the underside of the stage, is made of metal, and is at least partially immersed in the heat transfer fluid in the storage tank. The storage tank also includes a tank body, a supply port, an outlet, and an agitator. The supply port supplies the heat transfer fluid into the tank body. The outlet discharges the heat transfer fluid from the tank body. The agitator is configured to agitate the heat transfer fluid in the tank body.

[0006] According to various aspects and embodiments of the present disclosure, the temperature of a stage that supports a substrate can be adjusted more efficiently.

[0007] FIG. 1 is a diagram illustrating an example of the configuration of a capacitively coupled plasma processing apparatus. FIG. 2 is a diagram illustrating an example of the detailed structure of a substrate support unit. FIG. 3 is a diagram illustrating an example of how a coolant is stirred. FIG. 4 is a diagram illustrating another example of a method for connecting an electrostatic chuck and a heat transfer rod. FIG. 5 is a diagram illustrating another example of the structure of a tank main body. FIG. 6 is a diagram illustrating another example of the position of the stirring unit. FIG. 7 is a diagram illustrating an example of how the coolant is stirred. FIG. 8 is a diagram illustrating an example of how the coolant is stirred. FIG. 9 is a diagram illustrating another example of the connection position of piping. FIG. 10 is a diagram illustrating an example of how the coolant is stirred. FIG. 11 is a diagram illustrating an example of how the coolant is stirred. FIG. 12 is a diagram illustrating another example of the stirring unit. FIG. 13 is a diagram illustrating another example of the stirring unit. FIG. 14 is a diagram illustrating another example of an electrostatic chuck. FIG. 15 is a diagram illustrating another example of the structure of a substrate support unit. FIG. 16 is a diagram illustrating another example of the structure of a substrate support unit. FIG. 17 is a diagram illustrating an example of an arrangement of heat transfer rods on the underside of an electrostatic chuck. FIG. 18 is a diagram illustrating another example of the detailed structure of a substrate support unit.

[0008] Hereinafter, embodiments of a temperature adjustment device and a plasma processing apparatus will be described in detail with reference to the drawings. Note that the temperature adjustment device and the plasma processing apparatus disclosed below are not limited to the following embodiments.

[0009] In processes using plasma, the temperature of the substrate rises, and therefore the substrate must be cooled to maintain the temperature at a predetermined level. However, in processes using even higher-power plasma, it may be difficult to maintain the substrate temperature at a desired level using conventional cooling methods. Therefore, there is a need for a more efficient method of adjusting the substrate temperature.

[0010] Therefore, the present disclosure provides a technique that can more efficiently adjust the temperature of a stage that supports a substrate.

[0011] [Configuration of Plasma Processing System] An example of the configuration of a plasma processing system will be described below: Fig. 1 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus.

[0012] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a controller 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one processing gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0013] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 is an example of a temperature adjustment device. The main body 111 has a central region 111a for supporting a 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 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0014] In one embodiment, the main body 111 includes an electrostatic chuck 1111 and a cooling mechanism 60. The electrostatic chuck 1111 is an example of a stage, and the cooling mechanism 60 is an example of a storage tank. The electrostatic chuck 1111 is disposed on the cooling mechanism 60. The electrostatic chuck 1111 includes a ceramic member 1111a, an electrostatic electrode 1111b disposed within the ceramic member 1111a, and at least one radio frequency (RF) / direct current (DC) electrode 1111c. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, the RF / DC electrode 1111c is disposed within the ceramic member 1111a and is coupled to an RF power supply 31 and / or a DC power supply 32, which will be described later. The RF / DC electrode 1111c functions as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the RF / DC electrode 1111c, the RF / DC electrode 1111c is also called a bias electrode. Note that the electrostatic electrode 1111b may also function as a lower electrode. In this case, the RF power supply 31 and / or the DC power supply 32, which will be described later, are coupled to the electrostatic electrode 1111b, and the RF / DC electrode 1111c is not provided.

[0015] 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 cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material. Note that the annular region 111b may also be provided with at least one of an electrostatic electrode 1111b and an RF / DC electrode 1111c.

[0016] The substrate support 11 also includes a temperature adjustment 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 adjustment module may include a cooling mechanism 60, a heater, or a combination thereof. For example, one or more heaters may be disposed within the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 111a.

[0017] In this embodiment, one ends of a plurality of heat transfer rods 1111g formed of metal in a rod shape are connected to the lower surface of the electrostatic chuck 1111. The heat transfer rods 1111g are an example of a heat transfer member. The cooling mechanism 60 has a tank 61, in which a refrigerant 63 at a temperature lower than room temperature is stored. The tank 61 is an example of a tank main body, and the refrigerant 63 is an example of a heat transfer fluid.

[0018] A coolant 63 whose temperature is controlled by the chiller unit 50 is supplied into the tank 61 via a pipe 50a. The coolant 63 supplied into the tank 61 is agitated within the tank 61. The coolant 63 in the tank 61 is returned to the chiller unit 50 via a pipe 50b. The other ends of the plurality of heat transfer rods 1111g are immersed in the coolant 63 in the tank 61. Heat exchange occurs between the coolant 63 in the tank 61 and the plurality of heat transfer rods 1111g, thereby cooling the electrostatic chuck 1111 via the plurality of heat transfer rods 1111g.

[0019] In order to increase the surface area of ​​the heat transfer rod 1111g, it is preferable to form multiple projections and depressions on the surface of the heat transfer rod 1111g, for example by roughening the surface of the heat transfer rod 1111g. This allows for more efficient heat exchange between the refrigerant 63 in the tank 61 and the heat transfer rod 1111g. In addition, in order to keep the temperature of the refrigerant 63 in the tank 61 low, it is preferable to use a member formed of a material such as a resin material having a lower thermal conductivity than the thermal conductivity of the heat transfer rod 1111g for the tank 61. In addition, in order to reduce the thermal conductivity of the tank 61, a cavity may be formed inside at least one of the side wall and bottom wall of the tank 61.

[0020] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0021] 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 process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0022] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate a plasma from one or more process gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0023] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. 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 generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0024] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). 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 generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0025] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the at least one lower electrode and configured to generate a first DC signal. The generated first bias DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0026] In various embodiments, at least one of the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either 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 period. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0027] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided 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 in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0028] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform 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 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. The program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The storage unit 2a2 may include a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0029] 2 is a diagram showing an example of the detailed structure of the substrate support unit 11. The substrate support unit 11 in this embodiment includes a main body 111 and a ring assembly 112, as shown in FIG. 2 . The main body 111 has an electrostatic chuck 1111 and a cooling mechanism 60. The cooling mechanism 60 includes a tank 61 and an agitator 65.

[0030] Tank 61 is made of a material, such as ceramic, that has a lower thermal conductivity than metal. Tank 61 is formed with a supply port 51a and a discharge port 51b. Pipe 50a is connected to supply port 51a, and refrigerant 63 supplied from pipe 50a is supplied into tank 61 via supply port 51a. Pipe 50b is connected to discharge port 51b, and refrigerant 63 in tank 61 is discharged to pipe 50b via discharge port 51b.

[0031] The tank 61 is provided below the electrostatic chuck 1111, and a seal member 62 is disposed between the electrostatic chuck 1111 and the tank 61. This prevents the coolant 63 in the tank 61 from leaking out of the tank 61.

[0032] One ends of a plurality of heat transfer rods 1111g made of metal are connected to the lower surface of the electrostatic chuck 1111. The lower surface of the electrostatic chuck 1111 and the one ends of the heat transfer rods 1111g are connected to each other by, for example, an adhesive having high thermal conductivity. Note that the lower surface of the electrostatic chuck 1111 and the one ends of the heat transfer rods 1111g may also be connected to each other by, for example, welding.

[0033] The other ends of the heat transfer rods 1111g are immersed in the coolant 63 in the tank 61. A DC power supply 1111d is connected to the electrostatic electrode 1111b in the electrostatic chuck 1111 via wiring embedded in the side wall of the tank 61 and the seal member 62. Furthermore, a power supply 30 is connected to the RF / DC electrode 1111c in the electrostatic chuck 1111 via wiring embedded in the side wall of the tank 61 and the seal member 62.

[0034] In this embodiment, the agitator 65 includes a drive unit 650, a shaft 651, and an agitator blade 652. The drive unit 650 is connected to one end of the shaft 651, and the agitator blade 652 is connected to the other end of the shaft 651. The agitator blade 652 is disposed within the tank 61. The drive unit 650 rotates the shaft 651, thereby rotating the agitator blade 652 together with the shaft 651. As the agitator blade 652 rotates, the refrigerant 63 within the tank 61 is agitated, as shown in FIG. 3, for example. This prevents uneven temperature distribution of the refrigerant 63 within the tank 61. Furthermore, agitating the refrigerant 63 within the tank 61 can quickly move the refrigerant 63 that has exchanged heat with the heat transfer rod 1111g from the vicinity of the heat transfer rod 1111g.

[0035] 2, the amount of the coolant 63 stored in the tank 61 is adjusted so that a gap is formed between the lower surface of the electrostatic chuck 1111 and the coolant 63. This prevents the coolant 63 from leaking out of the tank 61 and allows the coolant 63 to be efficiently agitated.

[0036] The embodiment has been described above. As described above, this embodiment is a temperature adjustment device (substrate support unit 11) for adjusting the temperature of a substrate (substrate W), and includes a stage (electrostatic chuck 1111), a storage tank (cooling mechanism 60), and a heat transfer member (heat transfer rod 1111g). The stage supports the substrate. The storage tank is provided below the stage and stores a heat transfer fluid (refrigerant 63). The heat transfer member is connected to the underside of the stage, is made of metal, and is at least partially immersed in the heat transfer fluid in the storage tank. The storage tank also includes a tank body (tank 61), a supply port (supply port 51a), an outlet (outlet port 51b), and an agitator (agitator 65). The supply port supplies the heat transfer fluid into the tank body. The outlet discharges the heat transfer fluid from the tank body. The agitator is configured to agitate the heat transfer fluid in the tank body. This allows the temperature of the stage supporting the substrate to be adjusted more efficiently.

[0037] In the above embodiment, the agitator includes an agitator blade (agitator blade 652), and the agitator agitates the heat transfer fluid in the tank body by rotating the agitator blade. This promotes heat exchange between the stage and the heat transfer fluid via the heat transfer member, allowing the stage temperature to be adjusted more efficiently.

[0038] In the above-described embodiment, the heat transfer members are rod-shaped, with one end connected to the underside of the stage and the other end immersed in the heat transfer fluid in the storage tank, thereby enabling efficient heat exchange between the stage and the heat transfer fluid via the heat transfer members.

[0039] In the above-described embodiment, it is preferable that the surface of the heat transfer member is formed with a plurality of projections and recesses, thereby enabling more efficient heat exchange between the heat transfer fluid and the heat transfer member.

[0040] In the above-described embodiment, the tank body is made of a material having a lower thermal conductivity than metal, thereby making it possible to suppress temperature changes in the heat transfer fluid inside the tank body.

[0041] The plasma processing apparatus (plasma processing apparatus 1) in the above-described embodiment includes a chamber (plasma processing chamber 10), a temperature adjustment device provided within the chamber for adjusting the temperature of a substrate, and a plasma generation unit (RF power supply 31) for generating plasma within the chamber and performing plasma processing on the substrate whose temperature has been adjusted by the temperature adjustment device. The temperature adjustment device includes a stage, a storage tank, and a heat transfer member. The stage supports the substrate. The storage tank is provided below the stage and stores a heat transfer fluid. The heat transfer member is connected to the underside of the stage, is made of metal, and is at least partially immersed in the heat transfer fluid in the storage tank. The storage tank also includes a tank body, a supply port, an outlet, and an agitator. The supply port supplies the heat transfer fluid into the tank body. The outlet discharges the heat transfer fluid from the tank body. The agitator is configured to agitate the heat transfer fluid in the tank body. This allows the temperature of the stage supporting the substrate to be adjusted more efficiently.

[0042] [Others] The technology disclosed in the present application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.

[0043] For example, in the above-described embodiment, the lower surface of the electrostatic chuck 1111 and one ends of the heat transfer rods 1111g are connected to each other by, for example, an adhesive having high thermal conductivity, but the disclosed technology is not limited to this. As another example, as shown in FIG. 4, the electrostatic chuck 1111 and the plurality of heat transfer rods 1111g may be connected to each other by fitting one end of the heat transfer rod 1111g into a recess 1111h formed in the lower surface of the electrostatic chuck 1111.

[0044] In this case, corresponding thread grooves may be formed on the inner wall of the recess 1111h of the electrostatic chuck 1111 and the outer wall of one end of the heat transfer rod 1111g, and the electrostatic chuck 1111 and multiple heat transfer rods 1111g may be fixed together by a screw structure.

[0045] Alternatively, a protrusion may be formed on the lower surface of the electrostatic chuck 1111, a recess may be formed at one end of the heat transfer rod 1111g, and the protrusion formed on the lower surface of the electrostatic chuck 1111 may be fitted into the recess formed at one end of the heat transfer rod 1111g to fix the electrostatic chuck 1111. In this case, corresponding thread grooves may be formed on the outer wall of the protrusion on the lower surface of the electrostatic chuck 1111 and on the inner wall of the recess at one end of the heat transfer rod 1111g, and the electrostatic chuck 1111 and the plurality of heat transfer rods 1111g may be fixed together by a thread structure.

[0046] In the above-described embodiment, the entire tank 61 is formed of a material, such as a resin material, that has a lower thermal conductivity than metal, but the disclosed technology is not limited to this. As another example, as shown in FIG. 5 , the tank 61 may have an outer wall 61a made of a material with poor thermal insulation, such as aluminum, and an inner wall 61b made of a material, such as a resin material, that has a lower thermal conductivity than the heat transfer rods 1111g. To reduce the thermal conductivity of the inner wall 61b, a cavity may be formed in at least one of the side walls and bottom wall of the inner wall 61b. To further enhance thermal insulation, a vacuum space may be formed in at least one of the side walls and bottom wall of the tank 61.

[0047] In the above-described embodiment, the agitating blades 652 of the agitating unit 65 are disposed at the bottom of the tank 61, but the disclosed technology is not limited to this. As another example, as shown in Fig. 6, the agitating blades 652 of the agitating unit 65 may be disposed near the side wall of the tank 61. Even in this case, the agitating unit 65 can form a flow of the refrigerant 63 in the tank 61, as shown in Figs. 7 and 8, for example.

[0048] In the above embodiment, the refrigerant 63 is supplied into the tank 61 through the supply port 51a formed at the bottom of the tank 61 and discharged from the tank 61 through the discharge port 51b formed at the bottom of the tank 61. However, the disclosed technology is not limited to this. As another example, as shown in FIG. 9 , the supply port 51a may be formed at the upper part of the side wall of the tank 61, and the discharge port 51b may be formed at the lower part of the side wall of the tank 61. The refrigerant 63 immediately after being supplied into the tank 61 through the supply port 51a has not yet exchanged heat with the heat transfer rod 1111g, and therefore has a low temperature and a high specific gravity. Therefore, the refrigerant 63 supplied into the tank 61 through the supply port 51a flows from top to bottom within the tank 61. Then, after exchanging heat with the heat transfer rod 1111g, the refrigerant 63 is discharged through the discharge port 51b. This allows the refrigerant 63 in the tank 61 to be stirred more efficiently. The discharge port 51 b may be formed at the bottom of the tank 61 .

[0049] Alternatively, the discharge port 51b may be formed in the upper part of the side wall of the tank 61, and the supply port 51a may be formed in the lower part of the side wall of the tank 61. The refrigerant 63 supplied into the tank 61 from the supply port 51a increases in temperature and decreases in specific gravity during heat exchange with the heat transfer rods 1111g. Therefore, the refrigerant 63 that has exchanged heat with the heat transfer rods 1111g flows from bottom to top. The heated refrigerant 63 is then discharged from the discharge port 51b. This allows the heated refrigerant 63 to be quickly discharged.

[0050] Furthermore, when the supply port 51a and the discharge port 51b are formed in the side wall of the tank 61, a flow path 52a may be formed between the pipe 50a and the supply port 51a, and a flow path 52b may be formed between the pipe 50b and the discharge port 51b, as shown in Fig. 10, for example. In the example of Fig. 10, the flow path 52a rectifies the flow of the refrigerant 63 in a direction along the inner wall of the tank 61 and supplies it into the tank 61 via the supply port 51a. Furthermore, the flow path 52b discharges the heat transfer fluid flowing in a direction along the inner wall of the tank 61 via the discharge port 51b. The flow path 52a is an example of a first flow path, and the flow path 52b is an example of a second flow path.

[0051] 10, a flow of refrigerant 63 can be formed in tank 61, and refrigerant 63 can be efficiently stirred. Flow paths 52a and 52b can function as a stirring section that stirs refrigerant 63 in tank 61. Note that in the example of FIG. 10, supply port 51a and discharge port 51b may also be formed at positions at different heights on the side wall of tank 61, as shown in FIG. 9, for example.

[0052] 10, agitation unit 65 is provided, but agitation unit 65 may not be provided if flow paths 52a and 52b can sufficiently agitate refrigerant 63 in tank 61. Alternatively, as shown in FIG. 11, for example, a blade 66 that generates turbulence in refrigerant 63 in tank 61 may be provided in tank 61 instead of agitation unit 65. This allows refrigerant 63 in tank 61 to be agitated more efficiently.

[0053] 10, one pair of supply port 51a and flow path 52a is provided, and one pair of discharge port 51b and flow path 52b is provided, but the disclosed technology is not limited to this. As another example, two or more pairs of supply port 51a and flow path 52a may be provided, and two or more pairs of discharge port 51b and flow path 52b may be provided. This allows refrigerant 63 in tank 61 to be stirred more efficiently.

[0054] Furthermore, in the agitation unit 65 in the above-described embodiment, the refrigerant 63 in the tank 61 is agitated by rotating the agitation blades 652 in the tank 61, but the disclosed technology is not limited to this. As another example, as shown in Fig. 12, the agitation unit 65 may agitate the refrigerant 63 by vibrating the refrigerant 63.

[0055] The agitator 65 illustrated in Fig. 12 has a vibrator 653 and a vibration-proof mat 654. The vibrator 653 vibrates under the control of the controller 2 and agitates the refrigerant 63. The vibration-proof mat 654 prevents the vibration of the vibrator 653 from being transmitted to the tank 61. In the example of Fig. 12, the vibrator 653 directly vibrates the refrigerant 63, but as another example, the vibrator 653 may be installed outside the tank 61 and vibrate the tank 61, thereby vibrating the refrigerant 63 via the tank 61.

[0056] As another example of the agitation unit 65, for example, an agitation unit 65 as shown in Fig. 13 may be used. In the example of Fig. 13, the agitation unit 65 has a drive unit 655. The drive unit 655 rotates the tank 61. A cover 610 that protects the tank 61 is provided on the outside of the tank 61, and wiring connected to the electrostatic electrode 1111b and the RF / DC electrode 1111c is disposed within the seal member 62 and the cover 610.

[0057] Refrigerant 63 supplied from pipe 50a is supplied into tank 61 through supply port 51a, and refrigerant 63 in tank 61 is discharged to pipe 50b through discharge port 51b. When tank 61 is rotated by drive unit 655, a Couette flow is generated in refrigerant 63, and refrigerant 63 is agitated. Even with this configuration, refrigerant 63 can be agitated efficiently.

[0058] 2, the substrate support part 11 does not include a heater in the electrostatic chuck 1111, but the disclosed technology is not limited to this. As another example, a heater 1111e may be provided in the ceramic member 1111a of the electrostatic chuck 1111, as shown in Fig. 14. A heater power supply 1111f is connected to the heater 1111e.

[0059] 2, the wiring between the electrostatic electrode 1111b and the DC power supply 1111d and the wiring between the RF / DC electrode 1111c and the power supply 30 are embedded in the side wall of the tank 61 and the seal member 62, but the disclosed technology is not limited to this. As another example, as shown in Fig. 15, the wiring connecting the electrostatic electrode 1111b and the DC power supply 1111d and the wiring connecting the RF / DC electrode 1111c and the power supply 30 may be disposed in a wire introduction rod 611 provided substantially in the center of the tank 61. This allows the wiring connecting the electrostatic electrode 1111b and the DC power supply 1111d and the wiring connecting the RF / DC electrode 1111c and the power supply 30 to be shortened.

[0060] In the above embodiment, one end of each of the heat transfer rods 1111g is connected to the lower surface of the electrostatic chuck 1111 and supported by the electrostatic chuck 1111, but the other end of each of the heat transfer rods 1111g is not supported. However, the disclosed technology is not limited to this. As another example, the other end of each of the heat transfer rods 1111g may be supported by a support member 64 disposed between the other end of each of the heat transfer rods 1111g and the bottom of the tank 61, as shown in FIG. 16 . This can suppress deformation due to bending of the electrostatic chuck 1111 near its center. The support member 64 is preferably made of a material, such as a resin material, having a thermal conductivity lower than that of the heat transfer rods 1111g. Furthermore, a cavity may be formed inside the support member 64 to reduce the thermal conductivity of the support member 64.

[0061] Furthermore, it is preferable that the plurality of heat transfer rods 1111g are densely arranged in a region of the underside of the electrostatic chuck 1111 corresponding to a region of the substrate W where the temperature is relatively high, and are sparsely arranged in a region of the underside of the electrostatic chuck 1111 corresponding to a region of the substrate W where the temperature is relatively low. The region of the underside of the electrostatic chuck 1111 corresponding to a region of the substrate W where the temperature is relatively high is an example of a first region, and the region of the underside of the electrostatic chuck 1111 corresponding to a region of the substrate W where the temperature is relatively low is an example of a second region. For example, if the temperature near the edge of the substrate W tends to be high, the heat transfer rods 1111g are densely arranged in a region 1111i of the underside of the electrostatic chuck 1111 corresponding to the vicinity of the edge of the substrate W, as shown in FIG. 17 . In this case, the heat transfer rods 1111g are sparsely arranged in a region 1111j of the underside of the electrostatic chuck 1111 corresponding to the vicinity of the center of the substrate W, as shown in FIG. 17 . This makes it possible to improve the uniformity of the temperature distribution of the electrostatic chuck 1111, and to improve the in-plane uniformity of the temperature distribution of the substrate W.

[0062] In the above embodiment, the refrigerant 63 having a temperature lower than room temperature is used as the heat transfer fluid supplied into the tank 61, but the disclosed technology is not limited to this. A heat transfer medium having a temperature higher than room temperature may be used as the heat transfer fluid supplied into the tank 61.

[0063] Furthermore, in the above-described embodiment, a rod-shaped heat transfer rod 1111g is used as an example of a heat transfer member connected to the lower surface of the electrostatic chuck 1111, but the disclosed technology is not limited to this. As another example, the shape of the heat transfer member may be a shape other than a rod, such as a plate, fin, lattice, or cylinder. Furthermore, the heat transfer rod 1111g may be rod-shaped or not limited to a cylindrical shape. For example, the heat transfer rod 1111g may be prism-shaped, cone-shaped, frustum-shaped, or the like. Furthermore, the cross section of the cylindrical heat transfer rod 1111g is not limited to a perfect circle but may also be an ellipse.

[0064] Furthermore, in the above-described embodiment, the electrostatic chuck 1111 is used as an example of a stage, but the disclosed technology is not limited to this. As another example, the stage supporting the substrate W may be a metal plate such as aluminum. When the stage supporting the substrate W is a metal plate, the substrate is placed on the upper surface of the stage, and a heat transfer rod 1111g is connected to the back surface of the stage. Furthermore, as shown in FIG. 18 , for example, a metal plate 111i may be disposed between the electrostatic chuck 1111 and the heat transfer rod 1111g.

[0065] In the above embodiment, the plasma processing apparatus 1 has been described as using a capacitively coupled plasma (CCP) as an example of a plasma source, but the plasma source is not limited to the capacitively coupled plasma. Examples of plasma sources other than the capacitively coupled plasma include inductively coupled plasma (ICP), microwave-excited surface wave plasma (SWP), electron cyclotron resonance plasma (ECP), and helicon wave-excited plasma (HWP).

[0066] Furthermore, the embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. Indeed, the above-described embodiments can be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. Furthermore, the above-described embodiments and other examples can be appropriately combined within the scope that does not cause inconsistencies in function and configuration.

[0067] Furthermore, the following supplementary notes are disclosed regarding the above-described embodiment.

[0068] (Supplementary Note 1) A temperature adjustment device for adjusting the temperature of a substrate, comprising: a stage for supporting the substrate; a storage tank provided below the stage for storing a heat transfer fluid; and a heat transfer member connected to the underside of the stage, made of metal, and at least a portion of which is immersed in the heat transfer fluid in the storage tank, wherein the storage tank has: a tank body; a supply port for supplying the heat transfer fluid into the tank body; an outlet port for discharging the heat transfer fluid in the tank body; and an agitator configured to agitate the heat transfer fluid in the tank body. (Supplementary Note 2) The temperature adjustment device according to Supplementary Note 1, wherein the agitator includes an agitator blade, and the agitator agitates the heat transfer fluid in the tank body by rotation of the agitator blade. (Supplementary Note 3) The temperature adjustment device according to Supplementary Note 1 or 2, wherein the agitator includes a vibrator that vibrates the heat transfer fluid in the tank body, and the agitator agitates the heat transfer fluid in the tank body by vibration of the vibrator. (Supplementary Note 4) The temperature adjustment device according to any one of Supplements 1 to 3, wherein the stirring unit includes: a first flow path that rectifies the heat transfer fluid in a direction along the inner wall of the tank body and supplies it into the tank body through the supply port, and a second flow path that discharges the heat transfer fluid flowing in a direction along the inner wall of the tank body through the discharge port. (Supplementary Note 5) The temperature adjustment device according to Supplementary Note 4, wherein the first flow path and the second flow path are provided at different heights on the side wall of the tank body. (Supplementary Note 6) The temperature adjustment device according to Supplementary Note 1, wherein the stirring unit includes a drive unit that rotates the tank body, and the stirring unit is configured to stir the heat transfer fluid in the tank body by rotating the tank body with the drive unit. (Supplementary Note 7) The temperature adjustment device according to any one of Supplements 1 to 6, wherein the heat transfer member is a plurality of heat transfer rods formed in a rod shape, one end of which is connected to the underside of the stage and the other end of which is immersed in the heat transfer fluid in the storage tank. (Appendix 8) A temperature adjustment device according to Appendix 7, wherein the plurality of heat transfer rods are densely arranged in a region of the underside of the stage corresponding to a first region of the stage, and are sparsely arranged in a region of the underside of the stage corresponding to a second region of the stage that has a lower temperature than the first region.(Supplementary Note 9) The temperature adjustment device according to any one of Supplementary Notes 1 to 8, wherein a plurality of projections and recesses are formed on the surface of the heat transfer member. (Supplementary Note 10) The temperature adjustment device according to any one of Supplementary Notes 1 to 9, wherein the tank body is formed of a material having a lower thermal conductivity than metal. (Supplementary Note 11) The temperature adjustment device according to any one of Supplementary Notes 1 to 9, wherein a material having a lower thermal conductivity than metal is disposed inside the tank body. (Supplementary Note 12) The temperature adjustment device according to any one of Supplementary Notes 1 to 11, wherein a support member made of a material having a lower thermal conductivity than metal is disposed between the heat transfer member and the bottom of the tank body. (Supplementary Note 13) A plasma processing apparatus comprising: a chamber; a temperature adjustment device provided within the chamber to adjust the temperature of a substrate; and a plasma generation unit that generates plasma within the chamber and performs processing using the plasma on the substrate whose temperature has been adjusted by the temperature adjustment device, wherein the temperature adjustment device has: a stage that supports the substrate; a storage tank provided below the stage for storing a heat transfer fluid; and a heat transfer member connected to an underside of the stage, made of metal, and at least a portion of which is immersed in the heat transfer fluid in the storage tank, wherein the storage tank includes: a tank body; a supply port that supplies the heat transfer fluid into the tank body; an outlet port that discharges the heat transfer fluid in the tank body; and an agitation unit that agitates the heat transfer fluid in the tank body.

[0069] REFERENCE SIGNS LIST W substrate 1 plasma processing apparatus 2 control unit 2a computer 10 plasma processing chamber 11 substrate support unit 111 main body 1111 electrostatic chuck 1111a ceramic member 1111b electrostatic electrode 1111c RF / DC electrode 1111d DC power supply 1111e heater 1111f heater power supply 1111g heat transfer rod 1111h recess 112 ring assembly 13 shower head 20 gas supply unit 30 power supply 31 RF power supply 32 DC power supply 40 exhaust system 50 chiller unit 50a piping 50b piping 51a supply port 51b exhaust port 52a flow path 52b flow path 60 cooling mechanism 61 tank 61a outer wall 61b inner wall 610 cover 611 Wire guide rod 62 Sealing member 63 Refrigerant 64 Support member 65 Stirring unit 650 Driving unit 651 Shaft 652 Stirring blade 653 Vibrator 654 Anti-vibration mat 655 Driving unit 66 Blade

Claims

1. A temperature adjustment device for adjusting the temperature of a substrate, comprising: a stage for supporting the substrate; a storage tank provided below the stage for storing a heat transfer fluid; and a heat transfer member connected to the underside of the stage, made of metal, at least a portion of which is immersed in the heat transfer fluid in the storage tank, wherein the storage tank has: a tank body; a supply port for supplying the heat transfer fluid into the tank body; a discharge port for discharging the heat transfer fluid in the tank body; and a stirring unit configured to stir the heat transfer fluid in the tank body.

2. The temperature control device according to claim 1, wherein the stirring unit includes a stirring blade, and the stirring unit stirs the heat transfer fluid in the tank body by rotating the stirring blade.

3. A temperature control device as described in claim 1 or 2, wherein the stirring unit includes a vibrator that vibrates the heat transfer fluid in the tank body, and the stirring unit stirs the heat transfer fluid in the tank body by vibrating the vibrator.

4. A temperature control device as described in claim 1 or 2, wherein the stirring section includes a first flow path that rectifies the heat transfer fluid in a direction along the inner wall of the tank body and supplies it into the tank body through the supply port, and a second flow path that discharges the heat transfer fluid flowing in a direction along the inner wall of the tank body through the discharge port.

5. The temperature adjustment device according to claim 4, wherein the first flow path and the second flow path are provided at different heights on the side wall of the tank body.

6. The temperature control device according to claim 1, wherein the stirring unit includes a drive unit that rotates the tank body, and the stirring unit is configured to stir the heat transfer fluid within the tank body by rotating the tank body with the drive unit.

7. A temperature control device as described in claim 1 or 2, wherein the heat transfer member is a plurality of rod-shaped heat transfer rods, one end of which is connected to the underside of the stage and the other end of which is immersed in the heat transfer fluid in the storage tank.

8. A temperature control device as described in claim 7, wherein the plurality of heat transfer rods are densely arranged in an area on the underside of the stage corresponding to a first area of ​​the stage, and are sparsely arranged in an area on the underside of the stage corresponding to a second area of ​​the stage that has a lower temperature than the first area, compared to the first area.

9. The temperature adjustment device according to claim 1, wherein a plurality of projections and depressions are formed on the surface of the heat transfer member.

10. A temperature adjustment device according to claim 1 or 2, wherein the tank body is made of a material having a lower thermal conductivity than metal.

11. A temperature adjustment device according to claim 1 or 2, wherein a material having a lower thermal conductivity than metal is disposed inside the tank body.

12. A temperature control device according to claim 1 or 2, wherein a support member made of a material having a lower thermal conductivity than metal is disposed between the heat transfer member and the bottom of the tank body.

13. A plasma processing apparatus comprising: a chamber; a temperature adjustment device provided within the chamber for adjusting the temperature of a substrate; and a plasma generation unit for generating plasma within the chamber and performing processing using the plasma on the substrate whose temperature has been adjusted by the temperature adjustment device, wherein the temperature adjustment device has: a stage for supporting the substrate; a storage tank provided below the stage for storing a heat transfer fluid; and a heat transfer member connected to the underside of the stage, made of metal, and at least a portion of which is immersed in the heat transfer fluid in the storage tank, wherein the storage tank includes: a tank body; a supply port for supplying the heat transfer fluid into the tank body; an outlet port for discharging the heat transfer fluid in the tank body; and an agitation unit for agitating the heat transfer fluid in the tank body.

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