Substrate processing device

Abstract

To provide a substrate processing device that can increase the accuracy of temperature control of a substrate.SOLUTION: A substrate processing device includes a substrate support part that includes a substrate support surface and supports a substrate, a pump part configured to circulate a heat conduction gas in a first flow channel provided between the substrate and the substrate support surface, and a control unit. The substrate support part includes a second flow channel configured to connect the outlet of the first flow channel and the inlet of the pump part, and a third flow channel configured to connect the outlet of the pump part and the inlet of the first flow channel and including a path with the length that can adjust the temperature of the heat conduction gas to the temperature of the substrate support part below a flow channel of a temperature control medium that adjusts the temperature of the substrate support part. The control unit is configured to control the amount of circulation of the heat conduction gas in the pump part on the basis of the temperature measured in the second flow channel.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing apparatus. [Background technology]

[0002] Patent Document 1 discloses the following: "An electrostatic chuck having a chuck surface is provided. A plurality of sealing bands are located on the chuck surface, the plurality of sealing bands including an outer sealing band, a first inner band, a second inner band, and a third inner band. The plurality of cooling zones are defined by the plurality of sealing bands and include a first radial cooling zone defined by the outer sealing band and the first inner band, a second radial cooling zone defined by the first inner band and the second inner band, a third radial cooling zone defined by the second inner band and the third inner band, and a central cooling zone defined by the third inner band. The plurality of refrigerant gas ports include a first plurality of refrigerant gas ports, a second plurality of refrigerant gas ports, a third plurality of refrigerant gas ports, and a fourth plurality of refrigerant gas ports located in the first radial cooling zone, the second radial cooling zone, the third radial cooling zone, and the central cooling zone, respectively." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2020-512692 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a substrate processing apparatus capable of improving the accuracy of substrate temperature control. [Means for solving the problem]

[0005] A substrate processing apparatus according to one aspect of the present disclosure includes a substrate support unit having a substrate support surface and configured to support a substrate, a pump unit configured to circulate a heat transfer gas through a first flow path provided between the substrate and the substrate support surface, and a controller. The substrate support unit includes a second flow path configured to connect an outlet of the first flow path to an inlet of the pump unit, and a third flow path configured to connect the outlet of the pump unit to the inlet of the first flow path, the third flow path being located below the flow path of a temperature control medium that adjusts the temperature of the substrate support unit and including a path of a length sufficient to adjust the temperature of the heat transfer gas to the temperature of the substrate support unit. The controller is configured to control the amount of heat transfer gas circulated in the pump unit based on the temperature measured in the second flow path. [Effects of the Invention]

[0006] According to the present disclosure, the accuracy of substrate temperature control can be improved. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an example of a plasma processing system according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic cross-sectional view showing an example of the configuration of a plasma processing apparatus according to this embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view showing an example of the vicinity of a flow path of a heat transfer gas in this embodiment. [Figure 4] FIG. 4 is a view showing an example of a substrate support surface of an electrostatic chuck according to this embodiment. [Figure 5] FIG. 5 is a flowchart showing an example of plasma processing in this embodiment. [Figure 6] FIG. 6 is a diagram showing an example of a substrate support surface of an electrostatic chuck in the first modification. [Figure 7] FIG. 7 is a diagram showing an example of the first flow path in the second modification. [Figure 8] FIG. 8 is a diagram showing an example of the first flow path in the third modification. [Figure 9] FIG. 9 is a diagram showing an example of the first flow path in the fourth modification. [Figure 10] FIG. 10 is a diagram showing an example of a substrate support surface of an electrostatic chuck in the fifth modification. DETAILED DESCRIPTION OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments.

[0009] For example, in a substrate processing apparatus that performs plasma processing on a substrate, heat input from the plasma during the plasma process can increase the substrate temperature, affecting the process results. The temperature of the substrate support unit that supports the substrate can be controlled by circulating a temperature-control medium through a temperature-control medium flow path provided inside the substrate support unit. However, the gap between the substrate support surface and the substrate has high thermal resistance because heat is transferred by thermal diffusion of a supplied heat transfer gas (e.g., helium gas). This makes it difficult to control the substrate temperature through temperature control of the substrate support unit. Furthermore, it is difficult to control the temperature distribution within the substrate surface. Furthermore, to control the substrate temperature increase due to heat input from the plasma and the uniformity of the temperature distribution within the surface, one possible method is to increase the capacity of a chiller that circulates a temperature-control medium through a flow path within the substrate support unit. However, this would require a larger and more powerful chiller. Therefore, there is a need to maintain the substrate temperature as constant as possible, even when heat is input to the substrate, such as during plasma processing. In other words, there is a need to improve the accuracy of substrate temperature control.

[0010] [Configuration of plasma processing system] FIG. 1 illustrates an example of a plasma processing system according to an embodiment of the present disclosure. In this embodiment, the plasma processing system includes a plasma processing device 1 and a controller 2. The plasma processing system is an example of a substrate processing system, and the plasma processing device 1 is an example of a substrate processing device. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed within the plasma processing space and has a substrate support surface for supporting a substrate.

[0011] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Various types of plasma generating units may be used, including alternating current (AC) plasma generating units and direct current (DC) plasma generating units. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes a radio frequency (RF) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0012] 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).

[0013] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a schematic cross-sectional view showing an example of the configuration of the plasma processing apparatus according to this embodiment.

[0014] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, an exhaust system 40, and a heat transfer gas supply 60. 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 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0015] The substrate support 11 includes a main body 111 and a ring assembly 112. 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, in the following description, the central region 111a may be referred to as a substrate support surface 111a for supporting the substrate W, and the annular region 111b may be referred to as a ring support surface 111b for supporting the ring assembly 112.

[0016] 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 lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. 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, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32, which will be described later, may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Alternatively, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0017] 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.

[0018] The substrate support 11 may also include 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 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 in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 is also connected to a heat transfer gas supply unit 60 configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the substrate support surface 111a. The substrate support surface 111a is provided with a groove 111c, a heat transfer gas exhaust hole 53, and a heat transfer gas supply hole 54, which will be described later. A heat transfer gas exhaust path 51 is connected to the heat transfer gas exhaust hole 53, and a heat transfer gas supply path 52 is connected to the heat transfer gas supply hole 54. The heat transfer gas exhaust path 51 and the heat transfer gas supply path 52 are connected to a heat transfer gas supply unit 60. The heat transfer gas (backside gas) is, for example, helium gas.

[0019] The showerhead 13 is configured to introduce at least one processing 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 processing 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 introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0020] 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 at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0021] 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 processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

[0022] 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.

[0023] The second RF generating unit 31b is coupled to at least one lower electrode via at least one impedance matching circuit and 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 generating unit 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.

[0024] 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 at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to 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.

[0025] In various embodiments, 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. In one embodiment, a waveform generator for generating a 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.

[0026] 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 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.

[0027] [Details of heat transfer gas flow path] FIG. 3 is a schematic cross-sectional view showing an example of the vicinity of a flow path of the heat transfer gas in this embodiment. FIG. 4 is a diagram showing an example of a substrate support surface of an electrostatic chuck in this embodiment. As shown in FIGS. 3 and 4, the main body 111 of the substrate support part 11 has a spiral groove 111c formed, for example, in a single stroke, on the substrate support surface 111a. The groove 111c forms a first flow path 50 together with the back surface of the substrate W. That is, the first flow path 50 is formed by the back surface of the substrate W and the groove 111c provided in the substrate support surface 111a. In other words, the heat transfer gas flowing through the first flow path 50 comes into contact with the back surface of the substrate W, thereby cooling (regulating the temperature) the substrate W by forced convection, which has a higher heat dissipation capacity than thermal diffusion. Note that the heat dissipation capacity due to forced convection is approximately 10 to 100 times higher than the heat dissipation capacity due to thermal diffusion (natural convection).

[0028] Groove 111c is connected to heat transfer gas supply hole 54 at the end on the center side of substrate support surface 111a. Groove 111c is connected to heat transfer gas exhaust hole 53 at the end on the outer periphery side of substrate support surface 111a. Note that in FIG. 3, for the sake of explanation, heat transfer gas supply hole 54 and heat transfer gas exhaust hole 53 are drawn to appear on the same cross section, but heat transfer gas supply hole 54 and heat transfer gas exhaust hole 53 are positioned at both ends of groove 111c, as shown in FIG.

[0029] An outlet of the first flow path 50 is a heat transfer gas exhaust hole 53, which is connected to a heat transfer gas exhaust path 51. A thermometer 56 is connected to the heat transfer gas exhaust path 51 at a position near the bottom of the base 1110. A valve 57 is provided in the heat transfer gas exhaust path 51 between the bottom of the base 1110 and the heat transfer gas supply unit 60. The valve 57 is controlled, for example, to be opened after the substrate W is placed on the electrostatic chuck 1111, and to be closed before the substrate W is lifted from the electrostatic chuck 1111 by a lifter (not shown).

[0030] The inlet of the first flow path 50 is a heat transfer gas supply hole 54, which is connected to a heat transfer gas supply path 52. A pressure gauge 59 is connected to the heat transfer gas supply path 52 at a position near the bottom of the base 1110. A valve 58 is provided in the heat transfer gas supply path 52 between the bottom of the base 1110 and a heat transfer gas supply unit 60. The valve 58 is controlled, for example, to open after the substrate W is placed on the electrostatic chuck 1111 and to close before the substrate W is lifted from the electrostatic chuck 1111 by a lifter (not shown). A heat transfer gas supply source 66 (described later) is connected to the heat transfer gas supply path 52 via a pipe 64 and a valve 65. The heat transfer gas supply path 52 includes a path 55, located inside the base 1110 and below the flow path 1110a, which has a length that allows the temperature of the heat transfer gas to be adjusted to the temperature of the base 1110. That is, the path 55 is a flow path that circulates the heat transfer gas inside the base 1110 until the temperature of the heat transfer gas reaches the temperature of the base 1110. The path 55 may be provided at any location inside the base 1110, or may be provided inside the electrostatic chuck 1111, which has approximately the same temperature as the temperature of the base 1110.

[0031] The heat transfer gas supply unit 60 includes a pump 61 and a heat transfer gas supply source 66. The heat transfer gas exhaust path 51 is connected to an inlet 62 of the pump 61. The heat transfer gas supply path 52 is connected to an outlet 63 of the pump 61. That is, in the plasma processing apparatus 1, a path through which the heat transfer gas can circulate is formed in the order of the first flow path 50, the heat transfer gas exhaust path 51, the pump 61, and the heat transfer gas supply path 52. The heat transfer gas exhaust path 51 is an example of a second flow path, the heat transfer gas supply path 52 is an example of a third flow path, and the heat transfer gas supply unit 60 is an example of a pump unit. The heat transfer gas supply unit 60 may further include a heat exchanger (not shown) to cool (adjust the temperature of) the heat transfer gas.

[0032] The pump 61 is controlled to send and circulate the heat transfer gas through a circulatable path formed by the heat transfer gas supply path 52, the first flow path 50, and the heat transfer gas discharge path 51. The pipe 64 branches off from the heat transfer gas supply path 52 and is connected to a heat transfer gas supply source 66. The pipe 64 is provided with a valve 65. The heat transfer gas supply source 66 is controlled to supply the heat transfer gas to the heat transfer gas supply path 52 via the pipe 64 and the valve 65.

[0033] The circulation of the heat transfer gas starts from a state in which the valves 57, 58, and 65 are closed. For example, after the substrate W is attracted and held by the electrostatic chuck 1111, the valves 57 and 58 are controlled to open. Next, the valve 65 is controlled to open, and the heat transfer gas supply source 66 is controlled to supply the heat transfer gas to the heat transfer gas supply path 52. Note that an exhaust path (not shown) may be provided in the heat transfer gas circulation path. For example, exhaust may be performed from the heat transfer gas exhaust path 51 side, and then the exhaust path may be closed and the heat transfer gas may be supplied from the heat transfer gas supply path 52 side. Next, when the pressure in the heat transfer gas supply path 52 measured by the pressure gauge 59 increases to a predetermined pressure, the pump 61 is started, and the control unit 2 controls the pump 61 to start circulating the heat transfer gas. Here, the valve 65 is controlled to close. The control unit 2 controls the amount of heat transfer gas circulated by the pump 61 based on the temperature of the heat transfer gas in the heat transfer gas exhaust path 51 measured by the thermometer 56. That is, the discharge rate of the pump 61 is controlled so that the temperature of the heat transfer gas at the heat transfer gas supply hole 54, which is the inlet of the first flow path 50, becomes substantially the same as the temperature of the base 1110. The discharge rate of the pump 61 may be controlled so that the pressure in the first flow path 50 becomes constant. For example, if the pressure measured by the pressure gauge 59 is constant, it may be determined that the pressure in the first flow path 50 is constant.

[0034] For example, when the temperature measured by thermometer 56 is higher than the predicted temperature of the heat transfer gas that increases due to heat input in plasma processing, pump 61 is controlled to increase the amount of heat delivered. That is, pump 61 is controlled to increase the amount of heat transfer gas circulated. On the other hand, when the temperature measured by thermometer 56 is lower than the predicted temperature of the heat transfer gas that increases due to heat input in plasma processing, pump 61 is controlled to decrease the amount of heat delivered. That is, pump 61 is controlled to decrease the amount of heat transfer gas circulated.

[0035] When the plasma processing is completed, the pump 61 is controlled to stop, and the valves 57 and 58 are controlled to close. Thereafter, the substrate W is lifted by a lifter (not shown) and carried out.

[0036] [Temperature control method] Next, a method for controlling the temperature of the substrate W in this embodiment will be described below. Fig. 5 is a flowchart showing an example of plasma processing in this embodiment.

[0037] The control unit 2 controls a gate valve (not shown) to open a loading / unloading port. When the loading / unloading port is open, the substrate W is loaded into the plasma processing space 10s of the plasma processing chamber 10 through the loading / unloading port and is held by suction on the substrate support member 11. That is, the control unit 2 controls the plasma processing apparatus 1 to load the substrate W into the plasma processing chamber 10 (step S1). Note that the control unit 2 may also be a control device for the entire substrate processing system (not shown), including the plasma processing apparatus 1 and a transfer device in a transfer chamber (not shown) adjacent to the plasma processing chamber 10. The control unit 2 controls the gate valve to close the loading / unloading port.

[0038] The control unit 2 reduces the pressure in the plasma processing chamber 10 to a predetermined pressure by controlling the exhaust system 40 connected to the gas outlet 10e. The control unit 2 controls the gas supply unit 20 to supply plasma generating gas to the plasma processing chamber 10 through the multiple gas inlets 13c. The control unit 2 controls the heat transfer gas supply unit 60 to start circulating the heat transfer gas through a circulatable path formed by the heat transfer gas supply path 52, the first flow path 50, and the heat transfer gas exhaust path 51. At this time, the temperature of the substrate W is equal to the temperature of the main body 111 (the base 1110 and the electrostatic chuck 1111) before plasma ignition. The control unit 2 controls the RF power supply 31 to ignite plasma with a predetermined power. The control unit 2 starts plasma processing on the substrate W using the plasma of the plasma generating gas (step S2). Note that the plasma processing may include various plasma processes such as etching and film formation.

[0039] The control unit 2 acquires the temperature of the heat transfer gas from the thermometer 56 (step S3). The control unit 2 may continuously acquire the temperature of the heat transfer gas from the thermometer 56 from before the plasma is ignited. The control unit 2 controls the pump 61 of the heat transfer gas supply unit 60 to control the circulation amount of the heat transfer gas based on the temperature measured by the thermometer 56 (step S4). For example, the control unit 2 controls the heat transfer gas supply unit 60 to increase the circulation amount of the heat transfer gas so as to cool the substrate W in accordance with the heat input to the substrate W by the plasma.

[0040] The control unit 2 determines whether to terminate the plasma processing based on the process recipe (step S5). If the control unit 2 determines not to terminate the plasma processing (step S5: No), the control unit 2 returns to step S3 and controls the circulation amount of the heat transfer gas during the plasma processing again based on the temperature measured by the thermometer 56 in step S4. If the control unit 2 determines to terminate the plasma processing (step S5: Yes), the control unit 2 controls the RF power supply 31 to stop the RF signal and stop plasma generation. The control unit 2 also controls the gate valve to open the loading / unloading port. The control unit 2 controls the plasma processing apparatus 1 to lift the substrate W with a lifter (not shown). When the loading / unloading port is open, the substrate W is unloaded from the plasma processing chamber 10 by an arm of the transfer chamber (not shown) through the loading / unloading port. That is, the control unit 2 controls the plasma processing apparatus 1 to unload the substrate W from the plasma processing chamber 10 (step S6). In this way, the control unit 2 controls the circulation amount of the heat transfer gas during the plasma processing, thereby improving the accuracy of temperature control of the substrate W. For example, the control unit 2 can control the temperature of the substrate to a constant value. That is, the control unit 2 can improve the accuracy of temperature control of the substrate W, thereby expanding the range of process recipes that can be used. Furthermore, since heat transfer between the substrate support surface 111a and the substrate W is improved, the chiller that circulates a temperature control medium through the flow path 1110a in the substrate support unit 11 can also be made smaller and with a lower capacity.

[0041] [Variation 1] Next, Modifications 1 to 5 of this embodiment will be described with reference to FIGS. 6 to 10. FIG. 6 is a diagram showing an example of a substrate support surface of an electrostatic chuck in Modification 1. The plasma processing apparatus 1 of Modification 1 has an electrostatic chuck 1111c shown in FIG. 6 instead of the electrostatic chuck 1111. Note that the plasma processing apparatus 1 in Modification 1 is similar to the above-described embodiment except for the configuration of the electrostatic chuck 1111c, and therefore a description of the overlapping configuration and operation will be omitted. Also, the ring support surface 111b is omitted in FIG. 6.

[0042] 6, spiral grooves 111d and 111e are formed, for example, in a single stroke, on the substrate support surface 111a of the electrostatic chuck 1111c. The groove 111d is formed on the inner circumferential side of the substrate support surface 111a, and the groove 111e is formed on the outer circumferential side of the substrate support surface 111a. The groove 111d, together with the back surface of the substrate W, forms a first flow path 50a. That is, the first flow path 50a is formed by the back surface of the substrate W and the groove 111d provided in the substrate support surface 111a. The groove 111e, together with the back surface of the substrate W, forms a first flow path 50b. That is, the first flow path 50b is formed by the back surface of the substrate W and the groove 111e provided in the substrate support surface 111a.

[0043] Groove 111d is connected to heat transfer gas supply hole 54a at the end on the center side of substrate support surface 111a. Groove 111d is connected to heat transfer gas exhaust hole 53a at the end on the outer periphery side of substrate support surface 111a. That is, the outlet of first flow path 50a is heat transfer gas exhaust hole 53a, which is connected to heat transfer gas exhaust path 51. The inlet of first flow path 50a is heat transfer gas supply hole 54a, which is connected to heat transfer gas supply path 52.

[0044] The groove 111e is connected to the heat transfer gas supply hole 54b at the end of the substrate support surface 111a on the central side. The heat transfer gas supply hole 54b is, for example, arranged adjacent to the heat transfer gas exhaust hole 53a of the groove 111d. The groove 111e is also connected to the heat transfer gas exhaust hole 53b at the end of the substrate support surface 111a on the outer periphery side. That is, the outlet of the first flow path 50b is the heat transfer gas exhaust hole 53b, which is connected to the heat transfer gas exhaust path 51. The inlet of the first flow path 50b is the heat transfer gas supply hole 54b, which is connected to the heat transfer gas supply path 52. In this way, in the first modification, by dividing the substrate support surface 111a into two zones by the first flow path 50a on the inner periphery side and the first flow path 50b on the outer periphery side, it is possible to suppress a temperature increase of the heat transfer gas flowing through each of the first flow paths 50a and 50b. That is, in the first modification, even when the heat input to the substrate W is large, the accuracy of the temperature control of the substrate W can be improved.

[0045] [Variation 2] Fig. 7 is a diagram showing an example of a first flow path in Modification 2. The plasma processing apparatus 1 of Modification 2 has an electrostatic chuck 1111d shown in Fig. 7 instead of the electrostatic chuck 1111. The plasma processing apparatus 1 in Modifications 2 to 4 is similar to the above-described embodiment except for the configurations of the electrostatic chucks 1111d to 1111f, and therefore a description of the overlapping configurations and operations will be omitted. Also, in Figs. 7 to 9, the ring support surface 111b is omitted, and the regions corresponding to the second to fourth quadrants when the center of the substrate support surface 111a is regarded as the origin of the coordinate plane are omitted.

[0046] 7, on the substrate support surface 111a of the electrostatic chuck 1111d, a zigzag groove 111f is formed, for example, in a single stroke, in a quarter region of the substrate support surface 111a corresponding to the first quadrant. Note that the grooves 111f are formed in each of the quarter regions of the substrate support surface 111a corresponding to the second to fourth quadrants, similar to the region corresponding to the first quadrant. The grooves 111f, together with the back surface of the substrate W, form a first flow path 50c. That is, the first flow path 50c is formed by the back surface of the substrate W and the grooves 111f provided in the substrate support surface 111a.

[0047] The grooves 111f are connected to the heat transfer gas supply holes 54c at the end on the center side of the substrate support surface 111a. The grooves 111f are also connected to the heat transfer gas exhaust holes 53c at the end on the outer periphery side of the substrate support surface 111a. That is, the outlet of the first flow path 50c is the heat transfer gas exhaust hole 53c, which is connected to the heat transfer gas exhaust path 51. The inlet of the first flow path 50c is the heat transfer gas supply hole 54c, which is connected to the heat transfer gas supply path 52.

[0048] In this way, in Modification 2, by dividing the substrate support surface 111a into four zones by the first flow paths 50c in the regions corresponding to the first to fourth quadrants, it is possible to suppress a rise in temperature of the heat transfer gas flowing through each of the first flow paths 50c. That is, in Modification 2, even when the heat input to the substrate W is large, it is possible to improve the accuracy of temperature control of the substrate W.

[0049] [Variation 3] FIG. 8 is a diagram showing an example of a first flow path in Modification 3. The plasma processing apparatus 1 of Modification 3 has an electrostatic chuck 1111e shown in FIG. 8 instead of the electrostatic chuck 1111. As shown in FIG. 8, a spiral groove 111g is formed, for example, in a single stroke, on the substrate support surface 111a of the electrostatic chuck 1111e in a quarter region of the substrate support surface 111a corresponding to the first quadrant. Note that the groove 111g is formed in each of the quarter regions of the substrate support surface 111a corresponding to the second to fourth quadrants, similar to the region corresponding to the first quadrant. The groove 111g, together with the back surface of the substrate W, forms a first flow path 50d. That is, the first flow path 50d is formed by the back surface of the substrate W and the groove 111g provided in the substrate support surface 111a.

[0050] Groove 111g is connected to heat transfer gas supply hole 54d at the end toward the center of substrate support surface 111a. Groove 111g is also connected to heat transfer gas exhaust hole 53d at approximately the center of the region corresponding to the first quadrant. That is, the outlet of first flow path 50d is heat transfer gas exhaust hole 53d, which is connected to heat transfer gas exhaust path 51. The inlet of first flow path 50d is heat transfer gas supply hole 54d, which is connected to heat transfer gas supply path 52.

[0051] In this way, in Modification 3, by dividing the substrate support surface 111a into four zones by the first flow paths 50d in the regions corresponding to the first to fourth quadrants, it is possible to suppress a rise in temperature of the heat transfer gas flowing in each of the first flow paths 50d. That is, in Modification 3, even when the heat input to the substrate W is large, it is possible to improve the accuracy of temperature control of the substrate W.

[0052] [Variation 4] FIG. 9 is a diagram showing an example of a first flow path in Modification 4. The plasma processing apparatus 1 of Modification 4 has an electrostatic chuck 1111f shown in FIG. 9 instead of the electrostatic chuck 1111. As shown in FIG. 9, a spiral groove 111h is formed in a quarter region of the substrate support surface 111a of the electrostatic chuck 1111f corresponding to the first quadrant, with a set of round-trip grooves, for example, drawn in a single stroke. Note that the grooves 111h are formed in each of the quarter regions of the substrate support surface 111a corresponding to the second to fourth quadrants, similar to the region corresponding to the first quadrant. The grooves 111h, together with the rear surface of the substrate W, form a first flow path 50e. That is, the first flow path 50e is formed by the rear surface of the substrate W and the grooves 111h provided in the substrate support surface 111a.

[0053] The groove 111h is connected to the heat transfer gas supply hole 54e at one end toward the center of the substrate support surface 111a. The groove 111h is connected to the heat transfer gas exhaust hole 53e at the other end toward the center of the substrate support surface 111a. That is, the outlet of the first flow path 50e is the heat transfer gas exhaust hole 53e, which is connected to the heat transfer gas exhaust path 51. The inlet of the first flow path 50e is the heat transfer gas supply hole 54e, which is connected to the heat transfer gas supply path 52. The groove 111h is provided so as to turn back approximately at the center of the area corresponding to the first quadrant.

[0054] In this way, in Modification 4, by dividing the substrate support surface 111a into four zones by the first flow paths 50e in the regions corresponding to the first to fourth quadrants, it is possible to suppress a rise in temperature of the heat transfer gas flowing in each of the first flow paths 50e. That is, in Modification 4, even when the heat input to the substrate W is large, it is possible to improve the accuracy of temperature control of the substrate W.

[0055] [Variation 5] Fig. 10 is a diagram showing an example of a substrate support surface of an electrostatic chuck in Modification 5. The plasma processing apparatus 1 of Modification 5 has an electrostatic chuck 1111g shown in Fig. 10 instead of the electrostatic chuck 1111. Note that the plasma processing apparatus 1 in Modification 5 is similar to the above-described embodiment except for the configuration of the electrostatic chuck 1111g, and therefore a description of the overlapping configuration and operation will be omitted. Also, the ring support surface 111b is omitted in Fig. 10.

[0056] As shown in FIG. 10, a substrate support surface 111a of the electrostatic chuck 1111g is formed with a plurality of radial grooves 111i and a plurality of circumferential grooves 111j. The plurality of grooves 111i are provided, for example, from the innermost groove 111j to the outermost groove 111j. The plurality of grooves 111j are formed, for example, concentrically and connected at their intersecting points with each other. The plurality of grooves 111i, together with the rear surface of the substrate W, form a first flow path 50f. That is, the first flow path 50f is formed by the rear surface of the substrate W and the grooves 111i provided in the substrate support surface 111a. The plurality of grooves 111j, together with the rear surface of the substrate W, form a first flow path 50g. That is, the first flow path 50g is formed by the rear surface of the substrate W and the grooves 111j provided in the substrate support surface 111a.

[0057] The grooves 111i are connected to the heat transfer gas supply holes 54f or the innermost grooves 111j at the center end of the substrate support surface 111a. The grooves 111i are connected to the heat transfer gas exhaust holes 53f at the outer circumferential end of the substrate support surface 111a. The grooves 111i are also connected to each other via the grooves 111j. That is, the outlets of the first flow paths 50f and 50g are the heat transfer gas exhaust holes 53f, which are connected to the heat transfer gas exhaust path 51. The inlets of the first flow paths 50f and 50g are the heat transfer gas supply holes 54f, which are connected to the heat transfer gas supply path 52. That is, the heat transfer gas is supplied from the heat transfer gas supply holes 54f, flows through the first flow paths 50f and 50g, and is exhausted from the heat transfer gas exhaust holes 53f.

[0058] A thermometer 56 may be provided in each of the heat transfer gas discharge paths 51 connected to the plurality of heat transfer gas discharge holes 53f, and the flow rate and pressure of the heat transfer gas may be controlled so that the temperatures measured by the plurality of thermometers 56 are constant. In this case, the control unit 2 may generate a machine learning model using, as training data, the temperatures measured by the plurality of thermometers 56 and the flow rate and pressure of the heat transfer gas when performing plasma processing using a test substrate. When performing plasma processing on a substrate W to be processed, the control unit 2 may control the flow rate and pressure of the heat transfer gas using the trained machine learning model. For machine learning, algorithms such as a convolutional neural network (CNN) or a support vector machine (SVM) may be used.

[0059] In this way, in Modification 5, by providing the plurality of heat transfer gas supply holes 54f, the plurality of first flow paths 50f, 50g, and the plurality of heat transfer gas discharge holes 53f, it is possible to suppress a rise in the temperature of the heat transfer gas flowing through each of the plurality of first flow paths 50f, 50g. That is, in Modification 5, even when the heat input to the substrate W is large and the heat input is uneven across the surface of the substrate W, it is possible to improve the accuracy of temperature control of the substrate W.

[0060] As described above, according to this embodiment, the substrate processing apparatus (plasma processing apparatus 1) includes a substrate support unit 11, a pump unit (heat transfer gas supply unit 60), and a control unit 2. The substrate support unit 11 has a substrate support surface 111a and supports a substrate W. The pump unit is configured to circulate a heat transfer gas through a first flow path (first flow paths 50, 50a to 50g) provided between the substrate W and the substrate support surface 111a. The substrate support unit 11 includes a second flow path (heat transfer gas exhaust path 51) and a third flow path (heat transfer gas supply path 52). The second flow path is configured to connect an outlet of the first flow path (heat transfer gas exhaust holes 53, 53a to 53f) to an inlet 62 of the pump unit. The third flow path is configured to connect an outlet 63 of the pump unit to an inlet of the first flow path (heat transfer gas supply holes 54, 54a to 54f). The third flow path includes a path 55 having a length sufficient to adjust the temperature of the heat transfer gas to the temperature of the substrate support 11, below the flow path 1110a of the temperature control medium that adjusts the temperature of the substrate support 11. The control unit 2 is configured to control the amount of heat transfer gas circulated in the pump unit based on the temperature measured in the second flow path. As a result, the accuracy of temperature control of the substrate W can be improved.

[0061] Furthermore, according to this embodiment, the first flow path is formed by the rear surface of the substrate W and the grooves (grooves 111c to 111j) provided in the substrate support surface 111a. As a result, heat can be exchanged between the heat transfer gas and the rear surface of the substrate W, thereby improving the accuracy of temperature control of the substrate W.

[0062] Furthermore, according to this embodiment, the first flow path is a single-stroke flow path, which makes it possible to improve the temperature uniformity within the surface of the substrate W.

[0063] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and various omissions, substitutions, and modifications may be made to the above-described embodiments without departing from the scope and spirit of the appended claims.

[0064] In the above-described embodiment, plasma processing has been described as an example of substrate processing, but the present invention is not limited to this. For example, a heat transfer gas may be circulated between the substrate and a substrate support surface of a substrate processing apparatus that performs a process in which heat is input to the substrate W, such as an annealing process, and the amount of circulation of the heat transfer gas may be controlled, as in the embodiment.

[0065] In the above-described embodiment and modifications 1 to 4, the number of inlets and the number of outlets of the first flow paths 50, 50a to 50e correspond to one to one, but this is not limiting. For example, the number of inlets and the number of outlets of the first flow paths 50, 50a to 50e may correspond to one to N, N to one, or N to N. [Explanation of symbols]

[0066] 1. Plasma processing equipment 2. Control section 10 Plasma Processing Chamber 11 Substrate support 20 Gas supply unit 30 power supply 40 Exhaust system 50, 50a to 50g First flow path 51 Heat transfer gas exhaust channel 52 Heat transfer gas supply path 53, 53a to 53f Heat transfer gas exhaust hole 54, 54a to 54f Heat transfer gas supply holes 55 routes 60 Heat transfer gas supply section 61 Pump 62 Entrance 63 Exit 111a Board support surface 111c~111j Groove 1110a flow channel W substrate

Claims

1. a substrate support portion having a substrate support surface and supporting a substrate; a pump unit configured to circulate a heat transfer gas through a first flow path provided between the substrate and the substrate support surface; a control unit; The substrate support includes: a second flow path configured to connect an outlet of the first flow path and an inlet of the pump portion; a third flow path configured to connect an outlet of the pump unit and an inlet of the first flow path, the third flow path being located below a flow path of a temperature control medium that adjusts the temperature of the substrate support unit and including a path of a length that allows the temperature of the heat transfer gas to be adjusted to the temperature of the substrate support unit; The control unit is configured to control the circulation amount of the heat transfer gas in the pump unit based on the temperature measured in the second flow path. Substrate processing equipment.

2. the first flow path is formed by a rear surface of the substrate and a groove provided in the substrate support surface; The substrate processing apparatus according to claim 1 .

3. The first flow path is a unicursal flow path. The substrate processing apparatus according to claim 1 or 2.

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