Plasma processing apparatus and substrate attracting method

Abstract

Provided is a plasma processing apparatus and a substrate attracting method which enable suitable electrostatic attraction.　This plasma processing apparatus comprises: a plasma processing chamber; an electrostatic chuck that is disposed in the plasma processing chamber and that includes a dielectric member which has a substrate support surface and a ring support surface, and includes a plurality of chuck electrodes disposed below the ring support surface in the dielectric member; and an AC voltage generator configured to apply AC voltages, which are phase-shifted from one another, to the respective chuck electrodes. The plurality of chuck electrodes include one chuck electrode and another chuck electrode. The one chuck electrode has a plurality of circular arc parts and the other chuck electrode has a plurality of circular arc parts. The circular arc parts of the one chuck electrode and the circular arc parts of the other chuck electrode are alternately disposed in a radial direction.

Description

Plasma processing apparatus and substrate suction method

[0001] The present disclosure relates to a plasma processing apparatus and a substrate attracting method.

[0002] Japanese Patent Application Laid-Open No. 2003-144222 discloses an electrostatic attraction method for electrostatically attracting a focus ring provided on an electrostatic chuck.

[0003] Japanese Patent Application Laid-Open No. 2003-144999 discloses a substrate processing apparatus that applies an AC voltage to an electrode of an electrostatic chuck to electrostatically attract a substrate and an edge ring.

[0004] JP 2016-122740 A JP 2016-122740 A

[0005] In one aspect, the present disclosure provides a plasma processing apparatus and a substrate attracting method that are suitable for electrostatic attraction.

[0006] In order to solve the above problem, according to one aspect, there is provided a plasma processing apparatus including: a plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and a plurality of chuck electrodes disposed within the dielectric member below the ring support surface; and an AC voltage generator configured to apply AC voltages to the plurality of chuck electrodes, the AC voltages being phase-shifted from one another, respectively, wherein the plurality of chuck electrodes include one chuck electrode and another chuck electrode, the one chuck electrode having a plurality of arc portions and the other chuck electrode having a plurality of arc portions, the arc portions of the one chuck electrode and the arc portions of the other chuck electrodes being alternately arranged in a radial direction.

[0007] According to one aspect, it is possible to provide a plasma processing apparatus and a substrate attracting method that are capable of suitable electrostatic attraction.

[0008] 1 is a diagram illustrating an example of the configuration of a capacitively coupled plasma processing apparatus. FIG. 1 is a plan view illustrating an example of the arrangement of electrostatic electrodes of an electrostatic chuck. FIG. 2 is a plan view illustrating another example of the arrangement of electrostatic electrodes of an electrostatic chuck. FIG. 3 is a plan view illustrating yet another example of the arrangement of electrostatic electrodes of an electrostatic chuck. FIG. 4 is a graph illustrating an example of a two-phase AC voltage. FIG. 5 is a graph illustrating an example of a two-phase AC voltage. FIG. 6 is a schematic cross-sectional view illustrating residual adhesion of an edge ring. FIG. 7 is a schematic cross-sectional view illustrating residual adhesion of an edge ring. FIG. 8 is a test result when a DC voltage is applied to the electrostatic electrode. FIG. 9 is a test result when an AC voltage is applied to the electrostatic electrode. FIG. 10 is a flowchart illustrating an example of an edge ring replacement process. FIG. 11 is a time chart illustrating an example of a substrate adhesion process. FIG. 12 is a flowchart illustrating an example of a substrate adhesion release process. FIG. 13 is a time chart illustrating an example of a substrate adhesion release process. FIG. 14 is a time chart illustrating another example of a substrate adhesion release process. FIG. 15 is a cross-sectional view of an electrostatic chuck and an edge ring according to an embodiment. FIG. 16 is a graph illustrating an example of an AC voltage applied to the electrostatic electrode. FIG. 17 is a cross-sectional view of an electrostatic chuck and an edge ring according to another embodiment. 1A and 1B are cross-sectional views of an electrostatic chuck and an edge ring according to an embodiment; FIG. 1C is a cross-sectional view of an electrostatic chuck and an edge ring according to an embodiment; FIG. 1D is a cross-sectional view of an electrostatic chuck and an edge ring according to an embodiment; FIG. 1E is a partial enlarged view of an annular region of an electrostatic chuck; FIG. 1F is a cross-sectional view of an electrostatic chuck and an edge ring taken along B-B; FIG. 1G is a cross-sectional view of an electrostatic chuck and an edge ring taken along C-C; FIG. 1H is a cross-sectional view of an electrostatic chuck and an edge ring taken along D-D; FIG. 1H is a cross-sectional view of an electrostatic chuck and an edge ring taken along E-E; FIG. 1I is a plan view showing yet another example of an arrangement of electrostatic electrodes of an electrostatic chuck; FIG. 1I is a plan view showing yet another example of an arrangement of electrostatic electrodes of an electrostatic chuck; FIG. 1J is a graph showing the relationship between voltage and heat transfer gas flow; FIG. 1J is a graph showing an example of a temperature change in an edge ring; FIG. 1J is a graph showing an example of a temperature change in an edge ring; FIG. 1J is a partial enlarged cross-sectional view of a substrate support portion and a diagram showing the relationship with potential; FIG. 1I is a diagram showing a wafer chucking force in an example of plasma processing; FIG. 1I is a diagram showing a wafer chucking force in an example of plasma processing. 1A and 1B are enlarged cross-sectional views of a substrate support portion and an example of a diagram showing the relationship between the substrate support portion and potential;1 is a partial enlarged cross-sectional view of a substrate support portion and an example of a diagram showing the relationship between the substrate support portion and the potential;

[0009] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0010] [Plasma Processing System] An example of the configuration of a plasma processing system will be described below. Fig. 1 is an example of a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus (substrate processing apparatus) 1.

[0011] 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 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 into 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.

[0012] 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, 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.

[0013] 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 (dielectric member) 1111a, an electrostatic electrode 1111b disposed within the ceramic member 1111a, and an electrostatic electrode 1111c 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.

[0014] The ceramic member (dielectric member) 1111a has a substrate support surface (central region 111a) and a ring support surface (annular region 111b).

[0015] The electrostatic electrode 1111b is disposed below the central region 111a within the ceramic member 1111a. The electrostatic electrode 1111b includes N (N is an integer of 2 or greater) chuck electrodes (chuck electrodes 1111b1 to 1111b3 shown in FIG. 2, which will be described later) that are chuck electrodes. The plasma processing apparatus 1 includes a chuck power supply (AC voltage generator) 15 configured to apply voltages to the N chuck electrodes. The chuck power supply 15 applies N-phase AC voltages that are phase-shifted relative to each other to the N chuck electrodes. The N chuck electrodes are electrically connected to the chuck power supply 15. Thus, the electrostatic chuck 1111 includes first to N-th (N is an integer of 2 or greater) chuck electrodes 1111b1 to 1111b3 that are disposed below the substrate support surface (central region 111a) within the ceramic member 1111a. The chuck power supply 15 is configured to apply first to Nth AC voltages to the first to Nth chuck electrodes 1111b1 to 1111b3, respectively. The first to Nth AC voltages are phase-shifted from one another.

[0016] The electrostatic electrode 1111c is disposed within the ceramic member 1111a below the annular region 111b. The electrostatic electrode 1111c includes N (N is an integer of 2 or greater) chuck electrodes (chuck electrodes 1111c1 to 1111c2 shown in FIG. 2, which will be described later) that apply voltages to the N chuck electrodes. The chuck power supply 16 applies N-phase AC voltages that are phase-shifted relative to each other to the N chuck electrodes. The N chuck electrodes are electrically connected to the chuck power supply 16. Thus, the electrostatic chuck 1111 includes first to N-th (N is an integer of 2 or greater) chuck electrodes 1111c1 to 1111c2 that are disposed within the ceramic member 1111a below the ring support surface (annular region 111b). The chuck power supply 16 is configured to apply first to Nth AC voltages to the first to Nth chuck electrodes 1111c1 to 1111c2, respectively. The first to Nth AC voltages are phase-shifted from one another.

[0017] In the following description, the electrostatic electrode 1111b and the electrostatic electrode 1111c are each described as having a plurality of electrodes, but the configuration of the electrostatic chuck 1111 is not limited to this. Either the electrostatic electrode 1111b or the electrostatic electrode 1111c may be configured as a single electrode. Furthermore, either the electrostatic electrode 1111b or the electrostatic electrode 1111c may be configured to apply a DC voltage.

[0018] Note that other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have the annular region 111b. 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 (Radio Frequency) power supply 31 and / or a DC (Direct Current) power supply 32 (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 (described later) is supplied to the at least one RF / DC electrode, the RF / DC electrode is also referred to as 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.

[0019] 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 112A (see FIGS. 6A and 6B) and at least one cover ring. The edge rings 112A are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0020] 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 W 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 may also include a first heat transfer gas supply unit configured to supply a heat transfer gas to a gap between the backside of the substrate W and the central region 111a. The first heat transfer gas supply unit supplies the heat transfer gas to the gap between the backside of the substrate W and the central region 111a via a gas flow path that penetrates the base 1110 and a supply hole that penetrates the electrostatic chuck 1111.

[0021] The substrate support 11 may also include a second heat transfer gas supply unit configured to supply a heat transfer gas to a gap between the annular region 111 b and the rear surface of the edge ring 112A (see FIG. 15 , which will be described later) of the ring assembly 112. The second heat transfer gas supply unit supplies the heat transfer gas to the gap (including the diffusion grooves 113, which will be described later with reference to FIG. 15 and the like) between the annular region 111 b and the rear surface of the edge ring 112A of the ring assembly 112 via a gas flow path that penetrates the base 1110 and supply holes that penetrate the electrostatic chuck 1111.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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. This 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).

[0031] Next, an example of the electrostatic chuck 1111 will be described with reference to FIGS. 2 to 4. FIG. 2 is a plan view showing an example of the arrangement of the electrostatic electrodes 1111b and 1111c of the electrostatic chuck 1111. FIG. 3 is a plan view showing another example of the arrangement of the electrostatic electrodes 1111c of the electrostatic chuck 1111. FIG. 4 is a plan view showing yet another example of the arrangement of the electrostatic electrodes 1111c of the electrostatic chuck 1111. Note that in FIG. 2, the electrostatic electrode 1111b will be described as having three poles (N=3). Also, in FIGS. 3 to 4, the electrostatic electrode 1111b arranged below the central region 111a is not shown. Also, in FIGS. 2 to 4, the electrostatic electrode 1111c will be described as having two poles (N=2). Also, in FIGS. 2 to 4, the electrostatic electrode 1111c is clearly indicated by hatching.

[0032] 2, the electrostatic electrode 1111c includes a first chuck electrode 1111c1 and a second chuck electrode 1111c2. The first chuck electrode 1111c1 and the second chuck electrode 1111c2 are formed in concentric ring shapes.

[0033] The chuck power supply 16 includes a power supply 161 and a phase adjuster 162. The power supply 161 applies an AC voltage (first AC voltage) to the first chuck electrode 1111c1. The power supply 161 includes an AC power supply 161a and a DC power supply 161b. The AC power supply 161a generates an AC voltage and applies it to the first chuck electrode 1111c1. The DC power supply 161b generates a DC voltage and superimposes it on the AC voltage applied to the first chuck electrode 1111c1. The power supply 161 may include only one of the AC power supply 161a and the DC power supply 161b. A phase adjuster 162 is electrically connected between the power supply 161 and the second chuck electrode 1111c2. The phase adjuster 162 shifts the phase of the AC voltage supplied from the power supply 161 and supplies the phase-shifted AC voltage (second AC voltage) to the second chuck electrode 1111c2.

[0034] 2, the electrostatic electrode 1111b includes a first chuck electrode 1111b1, a second chuck electrode 1111b2, and a third chuck electrode 1111b3. The first chuck electrode 1111b1, the second chuck electrode 1111b2, and the third chuck electrode 1111b3 are formed in a spiral shape.

[0035] The chuck power supply 15 includes a power supply 151 and phase adjusters 152 and 153. The power supply 151 applies an AC voltage (first AC voltage) to the first chuck electrode 1111b1. The power supply 151 includes an AC power supply 151a and a DC power supply 151b. The AC power supply 151a generates an AC voltage and applies it to the first chuck electrode 1111b1. The DC power supply 151b generates a DC voltage and superimposes it on the AC voltage applied to the first chuck electrode 1111b1. The power supply 151 may include only one of the AC power supply 151a and the DC power supply 151b. A phase adjuster 152 is connected between the power supply 151 and the second chuck electrode 1111b2. The phase adjuster 152 shifts the phase of the AC voltage supplied from the power supply 151 and supplies the phase-shifted AC voltage (second AC voltage) to the second chuck electrode 1111b2. A phase adjuster 153 is connected between the power supply 151 and the third chuck electrode 1111b3. The phase adjuster 153 shifts the phase of the AC voltage supplied from the power supply 151 and supplies the phase-shifted AC voltage (third AC voltage) to the third chuck electrode 1111b3.

[0036] 3 , an electrostatic chuck 1111 includes an electrostatic electrode 1111c having a first chuck electrode 1111c1 and a second chuck electrode 1111c2. The first chuck electrode 1111c1 and the second chuck electrode 1111c2 are spirally formed. The electrostatic electrode 1111c includes a first arc-shaped portion 301, a second arc-shaped portion 302, a third arc-shaped portion 303, and a fourth arc-shaped portion 304, arranged in this order in the radial direction from the outer periphery toward the center. The electrostatic electrode 1111c also includes a first connecting portion 311 connecting the first arc-shaped portion 301 and the third arc-shaped portion 303, and a second connecting portion 312 connecting the second arc-shaped portion 302 and the fourth arc-shaped portion 304.

[0037] The first chuck electrode 1111c1 includes a first arcuate portion 301, a first connecting portion 311, and a third arcuate portion 303. The second chuck electrode 1111c2 includes a second arcuate portion 302, a second connecting portion 312, and a fourth arcuate portion 304.

[0038] Furthermore, in the second chuck electrode 1111c2, the second arc-shaped portion 302 includes an extending portion 302a extending toward the first arc-shaped portion 301. As a result, the extending portion 302a and / or the second arc-shaped portion 302 of the first chuck electrode 1111c1 are disposed on the outer circumferential side of the first connection portion 311, and the second connection portion 312 and / or the fourth arc-shaped portion 304 of the first chuck electrode 1111c1 are disposed on the inner circumferential side.

[0039] Furthermore, in the first chuck electrode 1111c1, the third arc portion 303 includes an extending portion 303a extending toward the fourth arc portion 304. As a result, the first arc portion 301 and / or the first connecting portion 311 of the second chuck electrode 1111c2 are arranged on the outer circumferential side of the second connecting portion 312, and the first connecting portion 311 and / or the extending portion 303a of the second chuck electrode 1111c2 are arranged on the inner circumferential side.

[0040] In the first chuck electrode 1111c1, the first connecting portion 311 connects one end of the first arc-shaped portion 301 to one end of the third arc-shaped portion 303. In the second chuck electrode 1111c2, the second connecting portion 312 connects one end of the second arc-shaped portion 302 to one end of the fourth arc-shaped portion 304. As a result, the first chuck electrode 1111c1 and the second chuck electrode 1111c2 are formed in a spiral shape.

[0041] The chuck power supply 16 includes a first power supply 163 and a second power supply 164. The first power supply 163 applies an AC voltage (first AC voltage) to the first chuck electrode 1111c1. The power supply 163 includes an AC power supply 163a and a DC power supply 163b. The AC power supply 163a generates an AC voltage and applies it to the first chuck electrode 1111c1. The DC power supply 163b generates a DC voltage and superimposes it on the AC voltage applied to the first chuck electrode 1111c1. The power supply 163 may include only one of the AC power supply 163a and the DC power supply 163b. The second power supply 164 applies an AC voltage (second AC voltage) to the second chuck electrode 1111c2. Here, the power supply 164 includes an AC power supply 164a and a DC power supply 164b. The AC power supply 164a generates an AC voltage and applies it to the second chuck electrode 1111c2. The DC power supply 164b generates a DC voltage and superimposes it on the AC voltage applied to the second chuck electrode 1111c2. Note that the power supply 164 may be configured to include only one of the AC power supply 164a and the DC power supply 164b. Furthermore, the AC voltage of the second power supply 164 (AC power supply 164a) is phase-shifted with respect to the AC voltage of the first power supply 163 (AC power supply 163a).

[0042] In yet another example of the electrostatic chuck 1111 shown in FIG. 4 , the electrostatic electrode 1111c includes a first chuck electrode 1111c1 and a second chuck electrode 1111c2. The first chuck electrode 1111c1 and the second chuck electrode 1111c2 are formed in a nested structure. The electrostatic electrode 1111c includes a first arc-shaped portion 401, a second arc-shaped portion 402, a third arc-shaped portion 403, and a fourth arc-shaped portion 404, arranged in this order in the radial direction from the outer periphery toward the center. The electrostatic electrode 1111c also includes a first connecting portion 411 connecting the first arc-shaped portion 401 and the third arc-shaped portion 403, and a second connecting portion 412 connecting the second arc-shaped portion 402 and the fourth arc-shaped portion 404.

[0043] The first chuck electrode 1111c1 includes a first arcuate portion 401, a first connecting portion 411, and a third arcuate portion 403. The second chuck electrode 1111c2 includes a second arcuate portion 402, a second connecting portion 412, and a fourth arcuate portion 404. The fourth arcuate portion 404 may be formed in a ring shape as shown in FIG.

[0044] In the second chuck electrode 1111c2, the second arcuate portion 402 includes an extending portion 402a extending toward the first arcuate portion 401 side.

[0045] In the first chuck electrode 1111c1, the first connecting portion 411 connects the middle of the first arc-shaped portion 401 (between one end of the first arc-shaped portion 401 and the other end of the first arc-shaped portion 401) to the middle of the third arc-shaped portion 403 (between one end of the third arc-shaped portion 403 and the other end of the third arc-shaped portion 403). In the second chuck electrode 1111c2, the second connecting portion 412 connects the middle of the second arc-shaped portion 402 (between one end of the second arc-shaped portion 402 and the other end of the second arc-shaped portion 402) to the middle of the fourth arc-shaped portion 404 (between one end of the fourth arc-shaped portion 404 and the other end of the fourth arc-shaped portion 404). As a result, the first chuck electrode 1111c1 and the second chuck electrode 1111c2 are formed in a nested structure.

[0046] The electrostatic electrode 1111c shown in Fig. 2 may be configured to have an AC voltage applied thereto from a first power supply 163 and a second power supply 164 as shown in Fig. 3. The electrostatic electrode 1111c shown in Fig. 3 may be configured to have an AC voltage applied thereto from a power supply 161 and a phase adjuster 162 as shown in Fig. 2. The electrostatic electrode 1111c shown in Fig. 4 may be configured to have an AC voltage applied thereto from a power supply 161 and a phase adjuster 162 as shown in Fig. 2, or may be configured to have an AC voltage applied thereto from a first power supply 163 and a second power supply 164 as shown in Fig. 3.

[0047] Although the electrostatic electrode 1111b shown in FIG. 2 is described as being formed in a spiral shape, this is not limiting. The electrostatic electrode 1111b may be formed in an annular shape (see the electrostatic electrode 1111c in FIG. 2) or in a nested structure (see the electrostatic electrode 1111c in FIG. 4). In one embodiment, the first to Nth chuck electrodes 1111b1 to 1111b3 have circular or ring shapes arranged concentrically. In one embodiment, the first to Nth chuck electrodes 1111b1 to 1111b3 have a spiral shape or a nested structure. In one embodiment, the first to Nth chuck electrodes 1111c1 to 1111c2 have ring shapes arranged concentrically. In one embodiment, the first to Nth chuck electrodes 1111c1 to 1111c2 have a spiral shape or a nested structure.

[0048] 2 has been described as including the power supply 151 and the phase adjusters 152 and 153, the present invention is not limited to this. A configuration in which three power supplies are electrically connected to the three chuck electrodes 1111b1 to 1111b3, respectively, may be used.

[0049] 5A and 5B are graphs showing examples of AC voltages. Fig. 5A is a graph showing an example of a two-phase AC voltage. Fig. 5B is a graph showing an example of a three-phase AC voltage. The vertical axis represents applied voltage, and the horizontal axis represents time.

[0050] In FIG. 5A, an example of the AC voltage applied to the first chuck electrode 1111c1 is shown by a solid line graph, and an example of the AC voltage applied to the second chuck electrode 1111c2 is shown by a dashed line graph.

[0051] The AC voltages applied by the chuck power supply 16 to each electrode (the first chuck electrode 1111c1 and the second chuck electrode 1111c2) of the electrostatic electrode 1111c have the same maximum amplitude, the same frequency, and different phases. For example, the phase difference between the AC voltages applied to the first chuck electrode 1111c1 and the second chuck electrode 1111c2 is set to 90°. This creates a potential difference ΔV between the first chuck electrode 1111c1 and the second chuck electrode 1111c2. By applying the voltages in this manner, the chucking force with which the electrostatic chuck 1111 attracts the edge ring 112A (see FIGS. 6A and 6B ) of the ring assembly 112 can be kept constant even if the electrostatic electrode 1111c has two poles.

[0052] Furthermore, when the number of poles of the electrostatic electrode 1111c is N, an N-phase AC voltage is expressed by the following equation (1) where A is the amplitude and f is the frequency, where n is an integer corresponding to each of the N or less electrodes. Fig. 5B shows an example of a three-phase AC voltage.

[0053] Asin(2πft+n / N×360°)...(1)

[0054] Furthermore, the phase difference between a certain electrode and another electrode on the inner periphery is (1 / N×360°), and the phase difference between another electrode on the outer periphery is (1 / N×360°). This makes it possible to reduce the potential difference between adjacent electrodes, thereby preventing short circuits between the electrodes.

[0055] In other words, the gap between the electrodes can be narrowed, and the area (radial width) of the electrodes can be increased. This increases the proportion of the ring support surface (annular region 111b) occupied by the electrostatic electrode 1111c. Here, the attracting force is generated at the position where the electrode is formed, and is not generated in the insulating region between the electrodes. With the electrostatic chuck 1111, increasing the area of ​​the electrode can improve the attracting force of the edge ring 112A. Furthermore, the in-plane uniformity of the attracting force can be improved. While the electrostatic electrode 1111c that attracts the edge ring 112A has been described as an example, the same applies to the electrostatic electrode 1111b that attracts the substrate W.

[0056] Next, electrostatic attraction of the edge ring 112A will be described with reference to Figures 6A and 6B, which are examples of schematic cross-sectional views showing residual attraction of the edge ring 112A.

[0057] 6A shows a case where a DC voltage is applied to the electrostatic electrode 1111c from the DC power supply 16A. Here, water molecules 600 may be attached to the back surface of the edge ring 112A (the surface that abuts against the ring support surface) due to cleaning of the edge ring 112A, storing the edge ring 112A in the air, or the like. As shown in the configuration of FIG. 6A , when a DC voltage is applied to the electrostatic electrode 1111c, the water molecules 600 are aligned and polarized so as to form an electric field opposite to the electric field formed between the electrostatic electrode 1111c and the edge ring 112A. This effectively weakens the adsorptive force between the edge ring 112A and the electrostatic chuck 1111.

[0058] Furthermore, after the application of the DC voltage from the DC power supply 16A to the electrostatic electrode 1111c is stopped, adsorption (residual adsorption) occurs due to the dipole moment of the water molecules 600. As a result, there is a risk that the edge ring 112A cannot be detached from the electrostatic chuck 1111 until the residual adsorption is reduced.

[0059] 6B shows a case where an AC voltage is applied to the electrostatic electrode 1111c from the chuck power supply 16. The chuck power supply 16 applies an AC voltage having a frequency faster than the polarization rate of the water molecules 600, specifically, a frequency in the range of 0.01 Hz to 100 Hz, to the electrostatic electrode 1111c. As a result, the time-averaged electric field becomes zero, thereby suppressing the polarization of the water molecules 600. This suppresses a decrease in the adsorptive force between the edge ring 112A and the electrostatic chuck 1111 due to the polarization of the water molecules 600. Furthermore, residual adsorption due to the polarization of the water molecules 600 can be suppressed.

[0060] Here, the results of a simulation test on the attraction force of the edge ring 112A will be described with reference to FIGS.

[0061] FIG. 7 shows test results when a DC voltage was applied to the electrostatic electrode 1111c. Here, the edge ring 112A was placed on the ring support surface of the electrostatic chuck 1111, and a DC voltage was applied to the electrostatic electrode 1111c from the DC power supply 16A. The chucking force was then measured. The initially measured chucking force (Try 1) is shown by the shaded bar graph. When the chucking force was less than the reference value (shown by the dashed-dotted line in FIG. 7), the polarity of the DC voltage applied from the DC power supply 16A to the electrostatic electrode 1111c was reversed three times to eliminate the polarization of the water molecules 600, and the chucking force was then measured again. The again measured chucking force (Try 2) is shown by the open bar graph.

[0062] Next, the DC voltage applied to the electrostatic electrode 1111c was stopped, and it was measured whether the edge ring 112A was lifted from the electrostatic chuck 1111. If the edge ring 112A was not lifted, the edge ring 112A was lifted every 5 minutes. The time until the edge ring 112A was lifted (in other words, the time until the residual adsorption was sufficiently reduced) is also recorded.

[0063] The above test was carried out four times.

[0064] As shown in Fig. 7, in the case of attraction using a DC voltage, many of the initially measured attraction forces (Try 1) were below the reference value (shown by the dashed line in Fig. 7). Moreover, the attraction forces (Try 2) measured again after the DC voltage was reversed three times exceeded the reference value, indicating that the attraction was favorably achieved.

[0065] 8 shows the test results when an AC voltage was applied to the electrostatic electrode 1111c. Here, the edge ring 112A was placed on the ring support surface of the electrostatic chuck 1111, and an AC voltage was applied to the electrostatic electrode 1111c from the chuck power supply 16. Thereafter, the chucking force was measured.

[0066] Next, the AC voltage applied to the electrostatic electrode 1111c was stopped, and it was measured whether the edge ring 112A was lifted from the electrostatic chuck 1111. If the edge ring 112A was not lifted, the edge ring 112A was lifted every 5 minutes. The time until the edge ring 112A was lifted (in other words, the time until the residual adsorption was sufficiently reduced) is also recorded.

[0067] The above test was carried out five times.

[0068] As shown in FIG. 8, in the case of attraction using an AC voltage, it was confirmed that the initially measured attraction force exceeded the reference value (shown by the dashed line in FIG. 8).

[0069] Furthermore, in the case of attraction using an AC voltage, the edge ring 112A could be lifted without waiting time (0 min). In other words, it was confirmed that residual attraction was sufficiently reduced.

[0070] <Edge Ring 112A Replacement Process> Next, a process for replacing the edge ring 112A (edge ​​ring replacement sequence) will be described with reference to FIG. 9. FIG. 9 is a flowchart showing an example of the edge ring 112A replacement process. Here, a case will be described in which a used edge ring (first edge ring) 112A placed on the ring support surface of the electrostatic chuck 1111 is replaced with an unused edge ring (second edge ring) 112A'.

[0071] At the start of the replacement process, a used edge ring (first edge ring) 112A is placed on the ring support surface of the electrostatic chuck 1111, an AC voltage is applied to the electrostatic electrode 1111c, and the used edge ring 112A is adsorbed to the electrostatic chuck 1111.

[0072] In step S101, the control unit 2 controls the chuck power supply 16 to stop the AC voltage applied to the electrostatic electrode 1111c.

[0073] In step S102, the controller 2 removes the used edge ring 112A from the ring support surface of the electrostatic chuck 1111. For example, the controller 2 controls a transport device (not shown) to remove the used edge ring 112A from the ring support surface of the electrostatic chuck 1111 and transport the used edge ring 112A out of the plasma processing chamber 10. Here, as shown in FIG. 8 , residual attraction can be suppressed by using an AC voltage as the voltage applied to the electrostatic electrode 1111c. This reduces or eliminates the waiting time until the residual attraction force decreases, allowing the used edge ring 112A to be removed.

[0074] In step S103, the control unit 2 places the unused edge ring (second edge ring) 112A′ on the ring support surface of the electrostatic chuck 1111. For example, the control unit 2 controls a transfer device (not shown) to load the unused edge ring 112A′ into the plasma processing chamber 10 and place the unused edge ring 112A′ on the ring support surface of the electrostatic chuck 1111.

[0075] In step S104, the control unit 2 controls the chuck power supply 16 to apply an AC voltage to the electrostatic electrode 1111c. Here, as shown in FIG. 8, the unused edge ring 112A′ can be suitably attracted by one suction process.

[0076] Therefore, the edge ring replacement sequence described above includes the following steps (a) to (d): (a) changing the first to Nth AC voltages applied to the first to Nth chuck electrodes 1111c1 to 1111c2, respectively, from an ON state to an OFF state, (b) removing the first edge ring 112A from the ring support surface (annular region 111b), (c) placing the second edge ring 112A' on the ring support surface (annular region 111b), and (d) changing the first to Nth AC voltages applied to the first to Nth chuck electrodes 1111c1 to 1111c2, respectively, from an OFF state to an ON state.

[0077] This allows the edge ring 112A to be electrostatically attracted in a suitable manner. Furthermore, the edge ring 112A' continues to be electrostatically attracted until it is replaced. Therefore, a configuration in which a DC voltage is applied may result in a large amount of residual attraction. In contrast, the use of an AC voltage can suppress the residual attraction.

[0078] The removal of the used edge ring 112A and the placement of the unused edge ring 112A' in steps S102 and S103 may be performed by an operator with the plasma processing chamber 10 open and exposed to the atmosphere.

[0079] <Suction Processing of Substrate W> Next, the suction processing of the substrate W (substrate chucking sequence) will be described with reference to FIGS. 10 and 11. FIG. 10 is a flowchart showing an example of the suction processing of the substrate W. FIG. 11 is a time chart showing an example of the suction processing of the substrate W. In FIG. 11, HF represents high frequency power for plasma generation. That is, it represents the source RF signal (source RF power) for plasma generation supplied by the first RF generator 31a to at least one lower electrode and / or at least one upper electrode. AC Voltage represents the voltage level (corresponding to amplitude A in equation (1)) of the high frequency voltage applied to the electrostatic electrode 1111b. A Frequency represents the frequency (corresponding to frequency f in equation (1)) of the high frequency voltage applied to the electrostatic electrode 1111b. The electrostatic electrode 1111b is, for example, a tripolar chuck electrode 1111b1, 1111b2, and 1111b3 (see FIG. 2 ), and radio frequency voltages with a phase difference of 120° are applied to each of the tripolar chuck electrodes 1111b1, 1111b2, and 1111b3 as shown in Equation (1). ACFR-a indicates the voltage level (corresponding to amplitude A in Equation (1)) of the radio frequency voltage applied to the first chuck electrode 1111c1. ACFR-b indicates the voltage level (corresponding to amplitude A in Equation (1)) of the radio frequency voltage applied to the second chuck electrode 1111c2. In the processes shown in FIGS. 10 and 11 , the edge ring 112A remains attracted to the electrostatic chuck 1111.

[0080] At the start of the adsorption process of the substrate W, the edge ring 112A is placed on the ring support surface of the electrostatic chuck 1111, an AC voltage is applied to the first chuck electrode 1111c1 and the second chuck electrode 1111c2, and the edge ring 112A is adsorbed to the electrostatic chuck 1111.

[0081] In step S201, the control unit 2 places the substrate W on the substrate support surface (central region 111a) of the electrostatic chuck 1111.

[0082] In step S202, the control unit 2 controls the plasma generation unit to generate a plasma for charge removal (first plasma) in the plasma processing chamber 10. Here, the first RF generation unit 31a supplies a source RF signal (source RF power) for plasma generation to at least one lower electrode and / or at least one upper electrode. This generates a plasma for charge removal in the plasma processing chamber 10. By exposing the surface of the substrate W to this plasma, the charge stored on the surface of the substrate W can be released.

[0083] In step S203, the control unit 2 controls the chuck power supply 15 to apply an AC voltage to the electrostatic electrode 1111b. Here, the AC voltage is applied at a first voltage level (corresponding to the amplitude A in Equation (1)) and a first frequency (corresponding to the frequency f in Equation (1)). Here, the first frequency is a frequency faster than the polarization rate of the water molecules 600, specifically, a frequency in the range of 0.01 Hz to 100 Hz.

[0084] In step S204, the control unit 2 controls the plasma generating unit to stop the generation of the static elimination plasma in the plasma processing chamber 10.

[0085] In step S205, the control unit 2 controls the chuck power supply 15 to change the frequency of the AC voltage applied to the electrostatic electrode 1111b. Here, while maintaining the first voltage level, the frequency is changed from the first frequency to a second frequency that is lower than the first frequency.

[0086] In step S206, the control unit 2 controls the plasma generation unit to generate plasma for substrate processing (second plasma) in the plasma processing chamber 10. Here, the first RF generation unit 31a supplies a source RF signal (source RF power) for plasma generation to at least one lower electrode and / or at least one upper electrode.

[0087] Therefore, the substrate chucking sequence described above includes the following steps (a) to (f): (a) placing a substrate W on the substrate support surface (central region 111a), (b) generating a first plasma in the plasma processing chamber 10, (c) applying first to Nth AC voltages to the first to Nth chuck electrodes 1111b1 to 1111b3, respectively (the first to Nth AC voltages have a first voltage level and a first frequency and are phase-shifted relative to each other), (d) stopping the generation of the first plasma, (e) changing the first to Nth AC voltages applied to the first to Nth chuck electrodes 1111b1 to 1111b3, respectively, to a second frequency greater than the first frequency while maintaining the first voltage level, and (f) generating a second plasma in the plasma processing chamber.

[0088] This generates a plasma for substrate processing in the plasma processing chamber 10. Also, the source RF power has a first power level in step (b), a zero power level in step (d), and a second power level greater than the first power level in step (f).

[0089] 10 and 11 , in step S203, the substrate W is electrostatically attracted at a first frequency that is higher than the frequency (second frequency) of the AC voltage applied to the electrostatic electrode 1111b in the substrate processing (S206). By applying an AC voltage to the electrostatic electrode 1111c at a frequency (e.g., a frequency in the range of 0.01 Hz to 100 Hz) that is faster than the polarization rate of water molecules 600 attracted to the surface of the substrate W, the electric field becomes zero as a time average, thereby suppressing the polarization of the water molecules 600. This suppresses a decrease in the attracting force between the edge ring 112A and the electrostatic chuck 1111 due to the polarization of the water molecules 600.

[0090] In step S205, the frequency of the AC voltage applied to the electrostatic electrode 1111b is changed to a second frequency (first frequency > second frequency), thereby suppressing the influence of the AC voltage applied to the electrostatic electrode 1111b on the substrate processing in step S206.

[0091] <Substrate W Adsorption Release Processing> Next, the substrate W adsorption release processing (substrate dechucking sequence) will be described with reference to FIGS. 12 to 14. FIG. 12 is a flowchart showing an example of the substrate W adsorption release processing. FIG. 13 is a time chart showing an example of the substrate W adsorption release processing. FIG. 14 is a time chart showing another example of the substrate W adsorption release processing. In FIGS. 13 and 14, HF represents the high frequency power for plasma generation. That is, it represents the source RF signal (source RF power) for plasma generation supplied by the first RF generator 31a to at least one lower electrode and / or at least one upper electrode. AC Voltage represents the voltage level of the high frequency voltage applied to the electrostatic electrode 1111b (corresponding to the amplitude A in equation (1)). A Frequency represents the frequency of the high frequency voltage applied to the electrostatic electrode 1111b (corresponding to the frequency f in equation (1)). The electrostatic electrode 1111b is, for example, a tripolar chuck electrode 1111b1, 1111b2, and 1111b3 (see FIG. 2 ), and radio frequency voltages with a phase difference of 120° are applied to each of the tripolar chuck electrodes 1111b1, 1111b2, and 1111b3 as shown in Equation (1). ACFR-a indicates the voltage level (corresponding to amplitude A in Equation (1)) of the radio frequency voltage applied to the first chuck electrode 1111c1. ACFR-b indicates the voltage level (corresponding to amplitude A in Equation (1)) of the radio frequency voltage applied to the second chuck electrode 1111c2. In the processes shown in FIGS. 10 and 11 , the edge ring 112A remains attracted to the electrostatic chuck 1111.

[0092] It is assumed that, at the start of the absorption / release process of the substrate W, the edge ring 112A is placed on the ring support surface of the electrostatic chuck 1111, AC voltages are applied to the first chuck electrode 1111c1 and the second chuck electrode 1111c2, and the edge ring 112A is attracted to the electrostatic chuck 1111. It is also assumed that the substrate W is placed on the substrate support surface of the electrostatic chuck 1111, AC voltages are applied to the first chuck electrode 1111b1 to the third chuck electrode 1111c3, and the substrate W is attracted to the electrostatic chuck 1111. It is assumed that the AC voltages applied to the first chuck electrode 1111b1 to the third chuck electrode 1111c3 have a first voltage level and a second frequency.

[0093] In step S301, the control unit 2 controls the plasma generating unit to generate plasma for substrate processing (second plasma) in the plasma processing chamber 10. In this way, plasma processing is performed on the substrate W. Here, the first RF generating unit 31a supplies a source RF signal (source RF power) for plasma generation to at least one lower electrode and / or at least one upper electrode. In this way, plasma for substrate processing is generated in the plasma processing chamber 10.

[0094] In step S302, the control unit 2 controls the chuck power supply 15 to change the frequency of the AC voltage applied to the electrostatic electrode 1111b. Here, while maintaining the first voltage level, the frequency is changed from the second frequency to a third frequency that is higher than the second frequency. Here, the third frequency is a frequency that is faster than the polarization rate of the water molecules 600, specifically, a frequency within the range of 0.01 Hz to 100 Hz.

[0095] In step S303, the control unit 2 controls the plasma generation unit to generate a neutralization plasma (third plasma) in the plasma processing chamber 10. Here, the first RF generation unit 31a supplies a plasma generation source RF signal (source RF power) to at least one lower electrode and / or at least one upper electrode. This generates a neutralization plasma in the plasma processing chamber 10. By exposing the surface of the substrate W to this plasma, the charge stored on the surface of the substrate W can be released.

[0096] In step S304, the control unit 2 controls the chuck power supply 15 to start reducing the voltage level of the AC voltage applied to the electrostatic electrode 1111b.

[0097] In step S305, the control unit 2 controls the plasma generating unit to stop the generation of the static elimination plasma in the plasma processing chamber 10.

[0098] As shown in FIG. 13, at the time when the plasma generation shown in step S305 is stopped, the voltage level of the AC voltage applied to the electrostatic electrode 1111b may be made sufficiently small, and after the plasma generation shown in step S305 is stopped, the voltage level of the AC voltage applied to the electrostatic electrode 1111b may be made zero.

[0099] 13 illustrates the voltage level of the AC voltage applied to the electrostatic electrode 1111b being reduced continuously, but this is not limiting. For example, the voltage level of the AC voltage applied to the electrostatic electrode 1111b may be reduced in multiple steps.

[0100] Furthermore, as shown in FIG. 14, the voltage level of the AC voltage applied to the electrostatic electrode 1111b may be set to zero before the plasma generation is stopped in step S305.

[0101] 12 to 14, in step S203, a third frequency is applied, which is a frequency higher than the frequency (second frequency) of the AC voltage applied to the electrostatic electrode 1111b in the substrate processing (S301). This makes it possible to suppress residual attraction between the edge ring 112A and the electrostatic chuck 1111 due to polarization of the water molecules 600.

[0102] Therefore, the substrate dechucking sequence described above includes the following steps (g) through (j): (g) changing the first through Nth AC voltages applied to the first through Nth chuck electrodes 1111b1 through 1111b3, respectively, to a third frequency greater than the second frequency while maintaining the first voltage level, (h) generating a third plasma in the plasma processing chamber, (i) initiating a decrease in the voltage levels of the first through Nth AC voltages applied to the first through Nth chuck electrodes 1111b1 through 1111b3, respectively, and (j) ceasing generation of the third plasma.

[0103] In one embodiment, step (j) is performed after the first through Nth AC voltages applied to the first through Nth chuck electrodes 1111b1-1111b3, respectively, are reduced to a zero voltage level. In one embodiment, step (j) is performed before the first through Nth AC voltages applied to the first through Nth chuck electrodes 1111b1-1111b3, respectively, are reduced to a zero voltage level.

[0104] Next, an example of electrostatic attraction of the edge ring 112A by the electrostatic electrode 1111c of the electrostatic chuck 1111 shown in FIG. 3 will be described with reference to FIGS.

[0105] FIG. 15 is an example of a cross-sectional view of an electrostatic chuck 1111 and an edge ring 112A according to an embodiment. Here, an electrostatic chuck 1111 having the electrostatic electrode 1111c shown in FIG. 3 will be described as an example. FIG. 15 is an example of a cross-sectional view of the electrostatic chuck 1111 and the edge ring 112A taken along line A-A (see FIG. 3). In FIG. 15 (and FIGS. 17 to 26 described below), the left side corresponds to the center side of the electrostatic chuck 1111, and the right side corresponds to the outer periphery side of the electrostatic chuck 1111.

[0106] A diffusion groove 113 is provided in the ring support surface (annular region 111b) of the electrostatic chuck 1111 that supports the edge ring 112A. The diffusion groove 113 diffuses a heat transfer gas into the gap between the edge ring 112A and the ring support surface. The diffusion groove 113 is a groove for diffusing the heat transfer gas (also referred to as back surface gas) supplied from a heat transfer gas supply unit through supply holes in the circumferential and radial directions of the ring support surface. The diffusion groove 113 is an annular groove concentric with the center of the electrostatic chuck 1111. Although not shown, the supply holes are connected to the diffusion groove 113.

[0107] The electrostatic electrode 1111c has a first arc-shaped portion 301, a second arc-shaped portion 302, a third arc-shaped portion 303, and a fourth arc-shaped portion 304, arranged in this order in the radial direction from the outer periphery toward the center. The first arc-shaped portion 301 and the third arc-shaped portion 303 are connected by a first connecting portion 311 (see FIG. 3), and the first arc-shaped portion 301 and the third arc-shaped portion 303 constitute a first chuck electrode 1111c1. The second arc-shaped portion 302 and the fourth arc-shaped portion 304 are connected by a second connecting portion 312 (see FIG. 3), and the second arc-shaped portion 302 and the fourth arc-shaped portion 304 constitute a second chuck electrode 1111c2.

[0108] The annular region 111b includes, from the outer periphery, a first annular region in which a first arc portion 301 is disposed, a second annular region in which a second arc portion 302 is disposed, a third annular region in which a third arc portion 303 is disposed, and a fourth annular region in which a fourth arc portion 304 is disposed. The first connecting portion 311 passes from the first arc portion 301 of the first annular region through the second annular region to the third arc portion 303 of the third annular region. The second arc portion 302 of the second annular region has a notch, and the first connecting portion 311 is disposed in the notch. The second connecting portion 312 passes from the second arc portion 302 of the second annular region through the third annular region to the fourth arc portion 304 of the fourth annular region. The third arcuate portion 303 of the third annular region has a cutout portion, and the second connecting portion 312 is disposed in the cutout portion.

[0109] 16 is a graph showing an example of an AC voltage applied to the electrostatic electrode 1111c. In FIG. 16, an example of an AC voltage applied to the first chuck electrode 1111c1 is shown by a solid line graph, and an example of an AC voltage applied to the second chuck electrode 1111c2 is shown by a dashed line graph. Here, the first chuck electrode 1111c1 is applied with an AC voltage of amplitude W ＡＣ An AC voltage of amplitude W ＡＣ 16, the AC voltage applied to the first chuck electrode 1111c1 is different in phase from the AC voltage applied to the second chuck electrode 1111c2 at time T1. At time T2, the voltage applied to the first chuck electrode 1111c1 is equal to the voltage applied to the second chuck electrode 1111c2.

[0110] 17 and 18 are cross-sectional views of an electrostatic chuck 1111 and an edge ring 112A according to another embodiment. Here, an example of an electrostatic chuck 1111 having the electrostatic electrode 1111c shown in FIG. 2 is shown. In FIG. 17, the magnitude of the chucking force at timing T1 (see FIG. 16) is indicated by the length of the outline arrow. In FIG. 18, the magnitude of the chucking force at timing T2 (see FIG. 16) is indicated by the length of the outline arrow.

[0111] 2 and 17 and 18 has a first chuck electrode 1111c1 and a second chuck electrode 1111c2 arranged in this order in the radial direction from the outer periphery toward the center, i.e., a double structure.

[0112] At timing T1 shown in FIG. 16 , the voltage applied to the second chuck electrode 1111c2 is greater than the voltage applied to the first chuck electrode 1111c1. Therefore, as shown in FIG. 17 , the attracting force F11 by the first chuck electrode 1111c1 is small, and the attracting force F12 by the second chuck electrode 1111c2 is large. This may cause a bias in the attracting force in the radial direction of the edge ring 112A, which may cause the outer periphery of the edge ring 112A to lift up. Although not shown, at a timing when the voltage applied to the first chuck electrode 1111c1 is greater than the voltage applied to the second chuck electrode 1111c2, the attracting force F11 by the first chuck electrode 1111c1 is large, and the attracting force F12 by the second chuck electrode 1111c2 is small. This may cause a bias in the attraction force in the radial direction of the edge ring 112A, which may cause the inner periphery of the edge ring 112A to lift up.

[0113] At timing T2 shown in Fig. 16, the voltage applied to the first chuck electrode 1111c1 and the voltage applied to the second chuck electrode 1111c2 are equal to each other, so that the attracting force F13 by the first chuck electrode 1111c1 and the attracting force F14 by the second chuck electrode 1111c2 are equal to each other, as shown in Fig. 18.

[0114] 2 and 17 and 18, the electrostatic chuck 1111 may have a reduced chucking stability of the edge ring 112A. The reduced chucking stability of the edge ring 112A may increase the amount of heat transfer gas leaking from the diffusion groove 113 into the plasma processing space 10s. Furthermore, the reduced contact between the edge ring 112A and the main body 111 may reduce the heat transfer from the edge ring 112A to the main body 111.

[0115] 19 and 20 are example cross-sectional views of an electrostatic chuck 1111 and an edge ring 112A according to an embodiment. Here, similar to FIG. 15 , an example of an electrostatic chuck 1111 having the electrostatic electrode 1111c shown in FIG. 3 is shown. In FIG. 19 , the magnitude of the chucking force at timing T1 (see FIG. 16 ) is indicated by the length of the outline arrow. In FIG. 20 , the magnitude of the chucking force at timing T2 (see FIG. 16 ) is indicated by the length of the outline arrow.

[0116] 3 and 19 and 20 has, in order in the radial direction from the outer periphery toward the center, a first arc-shaped portion 301 (first chuck electrode 1111c1), a second arc-shaped portion 302 (second chuck electrode 1111c2), a third arc-shaped portion 303 (first chuck electrode 1111c1), and a fourth arc-shaped portion 304 (second chuck electrode 1111c2). That is, the electrostatic chuck 1111 has a quadruple structure.

[0117] At timing T1 shown in FIG. 16 , the voltage applied to the second chuck electrode 1111c2 is greater than the voltage applied to the first chuck electrode 1111c1. Therefore, as shown in FIG. 19 , the attracting forces F21 and F23 of the first chuck electrode 1111c1 are small, and the attracting forces F22 and F24 of the second chuck electrode 1111c2 are large. However, because the first chuck electrode 1111c1 and the second chuck electrode 1111c2 are alternately arranged in the radial direction, the bias in the attracting force distribution in the radial direction of the edge ring 112A is suppressed. This suppresses the edge ring 112A from lifting up. Although not shown, the bias in the attracting force distribution in the radial direction of the edge ring 112A is also suppressed at a timing when the voltage applied to the first chuck electrode 1111c1 is greater than the voltage applied to the second chuck electrode 1111c2. This can prevent the edge ring 112A from floating up.

[0118] At timing T2 shown in Fig. 16, the voltage applied to the first chuck electrode 1111c1 and the voltage applied to the second chuck electrode 1111c2 are equal to each other, so that the attracting force F13 by the first chuck electrode 1111c1 and the attracting force F14 by the second chuck electrode 1111c2 are equal to each other, as shown in Fig. 20.

[0119] As described above, in the electrostatic chuck 1111 shown in FIGS. 3, 15, 19, and 20, the chuck electrodes 1111c1 and 1111c2 have a multi-ring structure. Specifically, the chuck electrode 1111c1 has a first arc-shaped portion 301 and a third arc-shaped portion 303, each having a different diameter. The chuck electrode 1111c2 has a second arc-shaped portion 302 and a fourth arc-shaped portion 304, each having a different diameter. The arc-shaped portions of the chuck electrode 1111c1 and the chuck electrode 1111c2 are alternately arranged in the radial direction. That is, one chuck electrode has multiple arc-shaped portions, and the other chuck electrode has multiple arc-shaped portions, and the arc-shaped portions of one chuck electrode and the other chuck electrode are alternately arranged in the radial direction. This prevents uneven distribution of the chucking force in the radial direction of the edge ring 112A. This prevents the edge ring 112A from lifting up.

[0120] The chuck electrode 1111c1 has a first connection portion 311 connecting the first arc-shaped portion 301 and the third arc-shaped portion 303. The chuck electrode 1111c2 has a second connection portion 312 connecting the second arc-shaped portion 302 and the fourth arc-shaped portion 304. This allows a voltage to be applied to the multiple arc-shaped portions from a single power source. This prevents an increase in the number of power supply lines from the power sources 163 and 164 to the chuck electrodes 1111c1 and 1111c2.

[0121] Although the diffusion groove 113 has been described as having an annular shape, the shape is not limited to this.

[0122] Fig. 21 is an example of a partial enlarged view of the annular region 111b of the electrostatic chuck 1111. The partial enlarged view shown in Fig. 21 is a view of the electrostatic chuck 1111 viewed from above. Fig. 22 is an example of a cross-sectional view of the electrostatic chuck 1111 and the edge ring 112A taken along line B-B. Fig. 23 is an example of a cross-sectional view of the electrostatic chuck 1111 and the edge ring 112A taken along line C-C.

[0123] The ring support surface (annular region 111b) of the electrostatic chuck 1111 that supports the edge ring 112A is provided with a diffusion groove 113. The diffusion groove 113 diffuses a heat transfer gas into a gap between the edge ring 112A and the ring support surface. The diffusion groove 113 is also a groove for diffusing the heat transfer gas (also referred to as a back surface gas) supplied from a supply hole (not shown) in the circumferential and radial directions of the ring support surface.

[0124] The diffusion groove 113 has an annular groove portion 113a and a plurality of radial groove portions 113b.

[0125] The annular groove 113a is provided in the ring support surface (annular region 111b) of the electrostatic chuck 1111, and is a groove having an annular shape concentric with the center of the electrostatic chuck 1111. Although not shown in the figure, a supply hole (not shown) communicates with the annular groove 113a.

[0126] The radial grooves 113b are provided in the ring support surface (annular region 111b) of the electrostatic chuck 1111, communicate with the annular groove 113a, and extend radially from the annular groove 113a to the electrostatic chuck 1111. As shown in FIG. 21 , the radial grooves 113b are formed as grooves extending radially outward and radially inward from the annular groove 113a. That is, one end of the radial grooves 113b is provided radially inward from the annular groove 113a. The other end of the radial grooves 113b is provided radially outward from the annular groove 113a.

[0127] 21 , the radial grooves 113b may be formed as grooves extending from the annular groove 113a radially outward and / or radially inward. Furthermore, the radial grooves 113b may be formed as grooves extending from the annular groove 113a radially outward and / or radially inward of the electrostatic chuck 1111.

[0128] In this way, the heat transfer gas supplied from the supply holes (not shown) is diffused in the circumferential direction of the ring support surface by the annular grooves 113a. Furthermore, the heat transfer gas is diffused in the radial direction of the ring support surface by the radial grooves 113b. That is, the heat transfer gas is diffused over the entire ring support surface.

[0129] Furthermore, when the ring support surface is viewed from above, the annular groove 113a is provided at a position that does not overlap with the arc portions 301 to 304 of the electrostatic electrode 1111c. In the example shown in Fig. 22, the annular groove 113a is provided on the outer circumferential side of the third arc portion 303 and on the inner circumferential side of the second arc portion 302. That is, in the radial direction, the inner circumferential side surface of the annular groove 113a coincides with or is located outside the outer circumferential end face of the third arc portion 303. Furthermore, in the radial direction, the outer circumferential side surface of the annular groove 113a coincides with or is located inside the inner circumferential end face of the second arc portion 302.

[0130] 22, the annular groove portion 113a and the arc portions 301 to 304 of the electrostatic electrode 1111c are described as being arranged in positions where they do not overlap, but this is not limited thereto. A partial overlap configuration is also possible. For example, when the inner circumferential side of the annular groove portion 113a overlaps with the third arc portion 303, it is preferable that the overlapping area between the annular groove portion 113a and the third arc portion 303 is 17% or less of the area of ​​the third arc portion 303. Similarly, when the outer circumferential side of the annular groove portion 113a overlaps with the second arc portion 302, it is preferable that the overlapping area between the annular groove portion 113a and the second arc portion 302 is 36% or less of the area of ​​the second arc portion 302.

[0131] In addition, when the ring support surface is viewed from above, the radial grooves 113b are provided at positions that partially overlap with the arc portions 301 to 304 of the electrostatic electrode 1111c. In the example shown in Fig. 23, the radial grooves 113b are provided so as to overlap with the second arc portion 302 and the third arc portion 303.

[0132] Next, the force of electrostatic attraction for attracting the edge ring 112A will be described.

[0133] Here, the attraction force F can be expressed by the following equation (2): where C is the combined capacitance, V is the voltage, and d is the distance between the electrodes (the distance between the electrostatic electrode 1111c and the edge ring 112A).

[0134] F = CV ２ / 2d...(2)

[0135] As shown in equation (1), even if the voltage V applied to each of the arc portions 301 to 304 of the electrostatic electrode 1111c is equal and the inter-plate distance d is equal, the adsorptive force F will differ if the combined capacitance C differs.

[0136] The annular groove portion 113a of the diffusion groove 113 is provided so as not to overlap with the electrostatic electrode 1111c. That is, the combined capacitances C of the first to fourth arc portions 301 to 304 are substantially equal. This allows the attracting forces of the first, second, third, and fourth arc portions 301, 302, 303, and 304 to be substantially equal. This improves the in-plane uniformity of the attracting force of the electrostatic chuck 1111. Furthermore, the improved in-plane uniformity of the attracting force allows for stable temperature control of the edge ring 112A. Furthermore, the improved in-plane uniformity of the attracting force allows for suppression of micro-vibrations of the edge ring 112A.

[0137] As described above, the electrostatic chuck 1111 according to this embodiment, which has the diffusion grooves 113, reduces the position dependency of the attracting force and improves the in-plane uniformity of the attracting force. Furthermore, the improved in-plane uniformity of the attracting force also improves the uniformity of cooling of the edge ring 112A.

[0138] The width of the annular groove portion 113a is preferably narrower than the distance between the third arc portion 303 and the second arc portion 302. In other words, the width is preferably within the range from the outer diameter of the third arc portion 303 to the inner diameter of the second arc portion 302.

[0139] The length (longitudinal width) of the radial grooves 113b is preferably a length that fits between the outer diameter of the fourth arc portion 304 and the inner diameter of the first arc portion 301. The overlap amount between each of the arc portions 302 and 303 and the diffusion groove 113 is determined based on the width of the annular groove portion 113a, the length (longitudinal width) of the radial grooves 113b, the number of the radial grooves 113b, and the width (transverse width) of the radial grooves 113b. The number of radial groove portions 113b and the width (short-side width) of the radial groove portions 113b are preferably sized such that, when the length (longitudinal width) of the radial groove portions 113b and the width of the annular groove portion 113a are determined, the overlap amount between the third arc portion 303 and the diffusion groove 113 is 24.5% or less with respect to the electrode area of ​​the third arc portion 303, and the overlap amount between the second arc portion 302 and the diffusion groove 113 is 45% or less with respect to the electrode area of ​​the second arc portion 302.

[0140] Fig. 24 is an example of a partial enlarged view of the annular region 111b of the electrostatic chuck 1111. The partial enlarged view shown in Fig. 24 is a view of the electrostatic chuck 1111 viewed from above. Fig. 25 is an example of a cross-sectional view of the electrostatic chuck 1111 and the edge ring 112A taken along line D-D. Fig. 26 is an example of a cross-sectional view of the electrostatic chuck 1111 and the edge ring 112A taken along line E-E.

[0141] The ring support surface (annular region 111b) of the electrostatic chuck 1111 that supports the edge ring 112A is provided with a diffusion groove 114. The diffusion groove 114 is a groove for diffusing a heat transfer gas (also referred to as a back surface gas) supplied from a supply hole (not shown) in the circumferential and radial directions of the ring support surface.

[0142] The diffusion groove 114 has an annular groove portion 114a1, an annular groove portion 114a2, and a plurality of radial groove portions 114b.

[0143] The annular grooves 114a1 and 114a2 are provided in the ring support surface (annular region 111b) of the electrostatic chuck 1111, and are annular grooves concentric with the center of the electrostatic chuck 1111. Although not shown in the figure, a supply hole (not shown) communicates with either the annular groove 114a1 or 114a2.

[0144] The radial grooves 114b are provided in the ring support surface (annular region 111b) of the electrostatic chuck 1111, communicate with the annular grooves 114a1 and 114a2, and extend radially from the annular grooves 114a1 and 114a2 of the electrostatic chuck 1111. That is, the radial grooves 114b communicate with the annular grooves 114a1 and 114a2. As shown in FIG. 24 , the radial grooves 114b are formed as grooves extending radially outward and radially inward from the annular grooves 114a1 and 114a2. That is, one end of the radial groove 114b is provided radially inward of the innermost annular groove 114a1 of the multiple annular grooves 114a1 and 114a2. The other end of the radial groove 114b is provided radially outward of the outermost annular groove 114a2 of the plurality of annular grooves 114a1, 114a2.

[0145] 24 , the radial grooves 114b may be formed as grooves extending radially outward and / or radially inward from the annular grooves 114a1 and 114a2. The radial grooves 114b may also be formed as grooves extending from the annular grooves 114a1 and 114a2 to at least one of the outer circumferential side and / or inner circumferential side of the electrostatic chuck 1111. The radial grooves 114b have been described as including a groove extending radially inward from the annular groove 114a1, a groove connecting the annular groove 114a1 to the annular groove 114a2, and a groove extending radially outward from the annular groove 114a2, which are linearly arranged. However, the present invention is not limited to this, and these grooves may be provided in separate segments.

[0146] In this way, the heat transfer gas supplied from the supply holes (not shown) is diffused in the circumferential direction of the ring support surface by the annular grooves 114a1 and 114a2. Furthermore, the heat transfer gas is diffused in the radial direction of the ring support surface by the radial grooves 114b. That is, the heat transfer gas is diffused over the entire ring support surface.

[0147] Furthermore, when the ring support surface is viewed from above, the annular grooves 114a1 and 114a2 are provided at positions that do not overlap with the arc portions 301 to 304 of the electrostatic electrode 1111c. In the example shown in FIG. 25 , the annular groove 114a1 is provided outer circumferentially of the fourth arc portion 304 and inner circumferentially of the third arc portion 303. That is, in the radial direction, the inner circumferential side surface of the annular groove 114a1 coincides with or is located outside the outer circumferential end face of the fourth arc portion 304. In addition, in the radial direction, the outer circumferential side surface of the annular groove 114a1 coincides with or is located inside the inner circumferential end face of the third arc portion 303. Furthermore, the annular groove 114a2 is provided outer circumferentially of the second arc portion 302 and inner circumferentially of the first arc portion 301. That is, in the radial direction, the inner peripheral side surface of the annular groove portion 114a2 coincides with or is located outside the outer peripheral end surface of the second arc portion 302. In addition, in the radial direction, the outer peripheral side surface of the annular groove portion 114a2 coincides with or is located inside the inner peripheral end surface of the first arc portion 301.

[0148] 25, the annular grooves 114a1 and 114a2 and the arcuate portions 301 to 304 of the electrostatic electrode 1111c are described as being provided at positions where they do not overlap, but this is not limitative. They may also be configured so that they partially overlap.

[0149] In addition, when the ring support surface is viewed from above, the radial grooves 114b are provided at positions that partially overlap with the arc portions 301 to 304 of the electrostatic electrode 1111c. In the example shown in Fig. 26, the radial grooves 114b are provided so as to overlap with the arc portions 301 to 304.

[0150] The number of annular groove portions included in the diffusion groove is not limited to this and may be three or more. For example, the diffusion groove may have an annular groove portion provided between the fourth arc portion 304 and the third arc portion 303, an annular groove portion provided between the third arc portion 303 and the second arc portion 302, and an annular groove portion provided between the second arc portion 302 and the first arc portion 301. The diffusion groove may have an annular groove portion provided on the inner circumferential side closer to the fourth arc portion 304. The diffusion groove may have an annular groove portion provided on the outer circumferential side closer to the first arc portion 301. The radial groove portions are provided to communicate these annular electrostatic electrodes.

[0151] Although the electrostatic electrode 1111c has been described as being provided in the form of a plurality of annular rings, this is not limiting. The electrostatic electrode 1111c may be formed by winding two electrodes in a spiral shape. In this case, the diffusion groove may have, in plan view, a spiral groove portion provided in a spiral shape between the two electrodes and a plurality of radial groove portions.

[0152] Furthermore, although the diffusion grooves 113, 114 provided in the ring support surface (annular region 111b) that supports the edge ring 112A have been described as an example, the present invention is not limited to this. The same may be applied to diffusion grooves in the substrate support surface (annular region 111b) that supports the substrate W. That is, the diffusion grooves provided in the substrate support surface (annular region 111b) may have one or more annular groove portions that are arranged so as not to overlap the electrostatic electrode 1111b in plan view, and a plurality of radial groove portions that communicate with the annular groove portions.

[0153] 3 has been described as an example, the electrostatic chuck 1111 shown in FIG. 4 can also be used to suppress bias in the distribution of the chucking force in the radial direction of the edge ring 112A. Furthermore, the edge ring 112A can be prevented from floating up. Furthermore, the number of power supply lines from the power supplies 163 and 164 to the chuck electrodes 1111c1 and 1111c2 can be reduced.

[0154] Furthermore, although the two-pole electrostatic electrode 1111c has been described as an example, the present invention is not limited to this and may be applied to a three-pole electrostatic electrode 1111c.

[0155] Fig. 27 is a plan view showing yet another example of the arrangement of the electrostatic electrodes 1111c of the electrostatic chuck 1111. As shown in Fig. 27, the electrostatic electrodes 1111c may be three-pole.

[0156] The electrostatic electrode 1111c has, in order in the radial direction from the outer periphery toward the center, a first arc portion 501, a second arc portion 502, a third arc portion 503, a fourth arc portion 504, a fifth arc portion 505, and a sixth arc portion 506. The electrostatic electrode 1111c also has a first connecting portion 511 connecting the first arc portion 501 and the fourth arc portion 504, a second connecting portion 512 connecting the second arc portion 502 and the fifth arc portion 505, and a third connecting portion 513 connecting the third arc portion 503 and the sixth arc portion 506.

[0157] The first chuck electrode 1111c1 includes a first arcuate portion 501, a first connecting portion 511, and a fourth arcuate portion 504. The second chuck electrode 1111c2 includes a second arcuate portion 502, a second connecting portion 512, and a fifth arcuate portion 505. The third chuck electrode 1111c3 includes a third arcuate portion 503, a third connecting portion 513, and a sixth arcuate portion 506.

[0158] The chuck power supply 16 includes a first power supply 163, a second power supply 164, and a third power supply 165. The first power supply 163 applies an AC voltage (first AC voltage) to the first chuck electrode 1111c1. The second power supply 164 applies an AC voltage (second AC voltage) to the second chuck electrode 1111c2. The third power supply 165 applies an AC voltage (third AC voltage) to the third chuck electrode 1111c3. The power supply 163 includes an AC power supply 163a and a DC power supply 163b. The AC power supply 163a generates an AC voltage and applies it to the first chuck electrode 1111c1. The DC power supply 163b generates a DC voltage and superimposes it on the AC voltage applied to the first chuck electrode 1111c1. The power supply 163 may be configured to include only one of the AC power supply 163a and the DC power supply 163b. Similarly, the power supply 164 includes an AC power supply 164a and a DC power supply 164b. The power supply 165 includes an AC power supply 165a and a DC power supply 165b. Furthermore, the AC voltages of the first power supply 163, the second power supply 164, and the third power supply 165 are phase-shifted from one another.

[0159] Fig. 28 is a plan view showing yet another example of the arrangement of the electrostatic electrodes 1111c of the electrostatic chuck 1111. As shown in Fig. 28, the electrostatic electrodes 1111c may be four-pole.

[0160] The electrostatic electrode 1111c has, in order in the radial direction from the outer periphery toward the center, a first arc portion 601, a second arc portion 602, a third arc portion 603, a fourth arc portion 604, a fifth arc portion 605, a sixth arc portion 606, a seventh arc portion 607, and an eighth arc portion 608. The electrostatic electrode 1111c also has a first connecting portion 611 connecting the first arc portion 601 and the fifth arc portion 605, a second connecting portion 612 connecting the second arc portion 602 and the sixth arc portion 606, a third connecting portion 613 connecting the third arc portion 603 and the seventh arc portion 607, and a fourth connecting portion 614 connecting the fourth arc portion 604 and the eighth arc portion 608.

[0161] The first chuck electrode 1111c1 includes a first arcuate portion 601, a first connecting portion 611, and a fifth arcuate portion 605. The second chuck electrode 1111c2 includes a second arcuate portion 602, a second connecting portion 612, and a sixth arcuate portion 606. The third chuck electrode 1111c3 includes a third arcuate portion 603, a third connecting portion 613, and a seventh arcuate portion 607. The fourth chuck electrode 1111c4 includes a fourth arcuate portion 604, a fourth connecting portion 614, and an eighth arcuate portion 608.

[0162] The chuck power supply 16 includes a first power supply 163, a second power supply 164, a third power supply 165, and a fourth power supply 166. The first power supply 163 applies an AC voltage (first AC voltage) to the first chuck electrode 1111c1. The second power supply 164 applies an AC voltage (second AC voltage) to the second chuck electrode 1111c2. The third power supply 165 applies an AC voltage (third AC voltage) to the third chuck electrode 1111c3. The fourth power supply 166 applies an AC voltage (fourth AC voltage) to the fourth chuck electrode 1111c4. The power supply 163 includes an AC power supply 163a and a DC power supply 163b. The AC power supply 163a generates an AC voltage and applies it to the first chuck electrode 1111c1. The DC power supply 163b generates a DC voltage and superimposes it on the AC voltage applied to the first chuck electrode 1111c1. Note that the power supply 163 may be configured to include only one of the AC power supply 163a and the DC power supply 163b. Similarly, the power supply 164 includes an AC power supply 164a and a DC power supply 164b. The power supply 165 includes an AC power supply 165a and a DC power supply 165b. The power supply 166 includes an AC power supply 166a and a DC power supply 166b. Furthermore, the AC voltages of the first power supply 163, the second power supply 164, the third power supply 165, and the fourth power supply 166 are phase-shifted from one another.

[0163] Next, the relationship between the voltage applied to the electrostatic electrode 1111c (chuck electrodes 1111c1 and 1111c2) and the chucking force will be further described with reference to Fig. 29. Fig. 29 is a graph showing the relationship between the voltage and the flow of the heat transfer gas.

[0164] In FIG. 29, "Amplitude" indicates the amplitude of the AC voltage applied to the electrostatic electrode 1111c. "Offset" indicates the offset voltage of the AC voltage applied to the electrostatic electrode 1111c. In the "Current Waveform Image," the horizontal axis indicates time, and the vertical axis indicates the voltage applied to the electrostatic electrode 1111c (chuck electrodes 1111c1 and 1111c2). The AC voltage applied to the chuck electrode 1111c1 is indicated by a solid line, and the AC voltage applied to the chuck electrode 1111c2 is indicated by a dashed line. The self-bias voltage Vdc (-1400 V in the example of FIG. 29) is indicated by a dotted line. ΔV ｍｉｎ is the minimum voltage difference between the voltage applied to the electrostatic electrode 1111c and the self-bias voltage Vdc. In (c) and (d), the offset voltage (average voltage for one period; center of the amplitude of the AC voltage) is schematically shown by a thick solid line. In "He flow," the horizontal axis represents time, and the vertical axis represents the flow rate of He gas (heat transfer gas) supplied to the diffusion groove 113.

[0165] For example, the power supply 161 includes an AC power supply 161 a and a DC power supply 161 b. The AC power supply 161 a generates an AC voltage and applies it to the first chuck electrode 1111 c 1. The DC power supply 161 b generates an offset voltage and superimposes it on the AC voltage applied to the first chuck electrode 1111 c 1.

[0166] (a) shows the case where the voltage applied to the electrostatic electrode 1111c has an amplitude of 4000 V and an offset voltage of 0 V. The minimum voltage difference ΔV ｍｉｎ The voltage is 1428 V. In this case, the flow rate of the He gas fluctuates. The variation width Δ of the flow rate of the He gas is 0.6 sccm. This indicates that the chucking force fluctuates.

[0167] (b) shows the case where the voltage applied to the electrostatic electrode 1111c has an amplitude of 5000 V and an offset voltage of 0 V. The minimum voltage difference ΔV ｍｉｎ is 2135 V. In other words, by increasing the amplitude of the applied voltage, the minimum voltage difference ΔV ｍｉｎIn this case, the fluctuation in the flow rate of the He gas is suppressed. The fluctuation width Δ of the flow rate of the He gas is 0.1 sccm. In other words, by increasing the amplitude of the applied voltage, the fluctuation in the chucking force is suppressed and the edge ring 112A is prevented from lifting up.

[0168] (c) shows the case where the voltage applied to the electrostatic electrode 1111c has an amplitude of 5000 V and a DC voltage is superimposed (offset) in the opposite direction to the self-bias voltage Vdc. Here, the offset is +1000 V. The minimum voltage difference ΔV ｍｉｎ is 1135 V. In other words, by offsetting the voltage in the opposite direction to the self-bias voltage Vdc, the minimum voltage difference ΔV ｍｉｎ becomes smaller. In this case, the flow rate of He gas fluctuates. The variation width Δ of the flow rate of He gas was 0.6 sccm. This indicates that fluctuations occur in the chucking force.

[0169] (d) shows the case where the voltage applied to the electrostatic electrode 1111c has an amplitude of 3600 V and is superimposed (offset) with a DC voltage in the same direction as the self-bias voltage Vdc. Here, the offset is -1400 V. The minimum voltage difference ΔV ｍｉｎ is 2545 V. In other words, by offsetting the DC voltage in the same direction as the self-bias voltage Vdc, the minimum voltage difference ΔV ｍｉｎ In this case, the fluctuation of the flow rate of He gas is suppressed. The fluctuation width Δ of the flow rate of He gas is 0.1 sccm. That is, the voltage applied to the electrostatic electrode 1111c is offset by a DC voltage in the same direction as the self-bias voltage Vdc, so that the minimum voltage difference ΔV ｍｉｎ This can increase the suction force, suppressing fluctuations in the suction force and preventing the edge ring 112A from floating up.

[0170] In this way, by offsetting the voltage applied to the electrostatic electrode 1111c with a voltage in the same direction as the self-bias voltage Vdc, it is possible to improve the stability of attraction while suppressing the amplitude.

[0171] Furthermore, by suppressing the amplitude of the voltage applied to the electrostatic electrode 1111c, power saving can be achieved.

[0172] The offset amount of the voltage applied to the electrostatic electrode 1111c is a DC voltage (negative DC voltage) in the same direction as the self-bias voltage Vdc (-1400 V in the example of FIG. 29). The offset amount of the voltage applied to the electrostatic electrode 1111c is preferably the self-bias voltage Vdc (see FIG. 29(d)). This allows the minimum voltage difference ΔV ｍｉｎ can be made larger.

[0173] The offset amount of the voltage applied to the electrostatic electrode 1111c is not limited to the self-bias voltage Vdc. The offset amount of the voltage applied to the electrostatic electrode 1111c is preferably within a range of 50% to 150% of the self-bias voltage Vdc.

[0174] That is, the control unit 2 controls the chuck power supply 16 to control the DC voltage (offset amount) to be superimposed on the AC voltage applied to the electrostatic electrode 1111c (chuck electrodes 1111c1 and 1111c2), thereby improving the stability of chucking while suppressing the amplitude.

[0175] Although the voltage applied to the electrostatic electrode 1111c that electrostatically attracts the edge ring 112A has been described, the present invention is not limited to this. The AC voltage applied to the electrostatic electrode 1111b that electrostatically attracts the substrate W may be offset by a DC voltage (negative DC voltage) having the same direction as the self-bias voltage Vdc.

[0176] Next, the relationship between the voltage applied to the electrostatic electrode 1111c (chuck electrodes 1111c1 and 1111c2) and the temperature of the edge ring 112A will be further described with reference to FIGS. 30A to 30C. FIGS. 30A to 30C are graphs showing an example of temperature change in the edge ring 112A. The horizontal axis represents time, and the vertical axis represents temperature change in the edge ring 112A. FIG. 30A shows the case where the frequency of the AC voltage applied to the electrostatic electrode 1111c is 0.1 Hz. FIG. 30B shows the case where the frequency of the AC voltage applied to the electrostatic electrode 1111c is 2 Hz. FIG. 30C shows the case where a DC voltage is applied to the electrostatic electrode 1111c.

[0177] 30B and 30C, the temperature of the edge ring 112A can be kept substantially constant.

[0178] 30A, the temperature of the edge ring 112A can be varied at a period T (10 sec) corresponding to the frequency (0.1 Hz) of the AC voltage. In this manner, by controlling the frequency of the AC voltage applied to the electrostatic electrode 1111c, the temperature of the edge ring 112A can be controlled while maintaining the attraction of the edge ring 112A.

[0179] That is, the control unit 2 controls the chuck power supply 16 to control the frequency of the AC voltage applied to the electrostatic electrode 1111c (chuck electrodes 1111c1 and 1111c2), thereby controlling the temperature of the edge ring 112A.

[0180] Although the voltage applied to the electrostatic electrode 1111c that electrostatically attracts the edge ring 112A has been described, the present invention is not limited to this. The temperature of the substrate W may be controlled by controlling the frequency of the AC voltage applied to the electrostatic electrode 1111b that electrostatically attracts the substrate W.

[0181] Next, a description will be given of the suction force for the substrate W. Note that the following description will be given of an example of suction for the substrate W, but is not limited to this, and the same applies to suction for the edge ring 112A of the ring assembly 112, so a duplicated description will be omitted.

[0182] FIG. 31 is an example of a partially enlarged cross-sectional view of the substrate support 11 and a diagram showing the relationship with the potential.

[0183] A source RF signal (hereinafter also referred to as HF) is supplied from the first RF generating unit 31 a to the conductive member of the base 1110, which functions as the lower electrode, and a bias RF signal (hereinafter also referred to as LF) is supplied from the second RF generating unit 31 b. In the examples of Figures 31 to 33, a DC voltage V_HV is applied to the electrostatic electrode 1111 b from the chuck power supply 15.

[0184] 31 , the potential of the base 1110 becomes the self-bias voltage Vdc. The potential increases from the upper surface of the base 1110 (the lower surface of the electrostatic chuck 1111) toward the electrostatic electrode 1111b, and the potential of the electrostatic electrode 1111b becomes the voltage V_HV applied from the chuck power supply 15. The potential decreases from the electrostatic electrode 1111b toward the rear surface of the substrate W (the substrate support surface of the electrostatic chuck 1111), and the potential of the rear surface of the substrate W (the substrate support surface of the electrostatic chuck 1111) becomes the self-bias voltage Vdc. The potential increases from the front surface of the substrate W toward the sheath of the plasma P, and the potential of the plasma P becomes the voltage Vp.

[0185] In this way, the potential difference between the rear surface of the substrate W and the electrostatic electrode 1111b is (V_HV-Vdc). Also, the electrostatic adsorption force (wafer adsorption force) of the substrate W is (V_HV-Vdc). ２ is proportional to.

[0186] FIG. 32 is a diagram showing the wafer chucking force in an example of plasma processing. Here, HF indicates the output of the source RF signal. LF indicates the output of the bias RF signal. The potential indicates the voltage V_HV applied from the chuck power supply 15 and the self-bias voltage Vdc. The wafer chucking force indicates the electrostatic chucking force of the substrate W. The horizontal axis indicates time. Here, plasma processing is performed on the substrate W using the HF and LF shown in FIG. 32. At this time, the self-bias voltage Vdc shown by the dashed line is generated. In plasma processing, the self-bias voltage Vdc changes depending on the plasma processing conditions (HF, LF).

[0187] Here, the control unit 2 controls the voltage V_HV (solid line) applied to the electrostatic electrode 1111b from the chuck power supply 15 to be constant. In this case, as the self-bias voltage Vdc changes, the wafer chucking force also changes.

[0188] FIG. 33 is a diagram showing the wafer chucking force in an example of plasma processing. Here, HF indicates the output of the source RF signal. LF indicates the output of the bias RF signal. The potential indicates the voltage V_HV applied from the chuck power supply 15 and the self-bias voltage Vdc. The wafer chucking force indicates the electrostatic chucking force of the substrate W. The horizontal axis indicates time. Here, plasma processing is performed on the substrate W using the HF and LF shown in FIG. 33. At this time, the self-bias voltage Vdc shown by the dashed line is generated. In plasma processing, the self-bias voltage Vdc changes depending on the plasma processing conditions (HF, LF).

[0189] Here, the control unit 2 controls the voltage V_HV (solid line) applied to the electrostatic electrode 1111b from the chuck power supply 15 so that (V_HV - Vdc) is constant. That is, the control unit 2 changes the voltage V_HV (solid line) applied to the electrostatic electrode 1111b from the chuck power supply 15 in accordance with the self-bias voltage Vdc (dashed line). This makes it possible to maintain a constant wafer chucking force.

[0190] Next, a case where the AC voltage V_HV is applied from the chuck power supply 15 to the electrostatic electrode 1111b will be described with reference to FIGS.

[0191] FIG. 34 is an example of a partially enlarged cross-sectional view of the substrate support 11 and a diagram showing the relationship with the potential.

[0192] A source RF signal (hereinafter also referred to as HF) is supplied from the first RF generator 31a to the conductive member of the base 1110, which functions as the lower electrode, and a bias RF signal (hereinafter also referred to as LF) is supplied from the second RF generator 31b. In the example of FIG. 34 (and FIGS. 36 and 37 described below), the electrostatic electrode 1111b has two electrodes (a first chuck electrode 1111b1 and a second chuck electrode 1111b2). The chuck power supply 15 includes a first AC power supply 156, a second AC power supply 157, and a DC power supply 158.

[0193] The first AC power supply 156 applies an AC voltage to the first chuck electrode 1111b1. The second AC power supply 157 applies an AC voltage to the second chuck electrode 1111b2. The DC power supply 158 is connected in series with the first AC power supply 156 and the second AC power supply 157.

[0194] FIG. 35 is a diagram showing the wafer chucking force in an example of plasma processing. Here, HF indicates the output of the source RF signal. LF indicates the output of the bias RF signal. The potential indicates the direct current (DC) component of the voltage V_HV applied from the chuck power supply 15 (i.e., the voltage component of the DC power supply 158) and the self-bias voltage Vdc. The wafer chucking force indicates the electrostatic chucking force of the substrate W. The horizontal axis indicates time. Here, plasma processing is performed on the substrate W using the HF and LF shown in FIG. 35. During this process, the self-bias voltage Vdc, shown by the dashed line, is generated. During plasma processing, the self-bias voltage Vdc varies depending on the plasma processing conditions (HF, LF).

[0195] Here, the control unit 2 controls the DC power supply 158 so that the DC component of the voltage V_HV applied from the chuck power supply 15 matches the self-bias voltage Vdc. That is, the control unit 2 controls the DC power supply 158 in accordance with the self-bias voltage Vdc. As a result, the chuck power supply 15 applies an AC voltage offset by the self-bias voltage Vdc to the first chuck electrode 1111b1 and the second chuck electrode 1111b2. This makes it possible to maintain a constant wafer chucking force.

[0196] FIG. 36 is an example of a partially enlarged cross-sectional view of the substrate support 11 and a diagram showing the relationship with the potential.

[0197] In this embodiment, the chuck power supply 15 includes a first AC power supply 156, a second AC power supply 157, and an RF filter 159. The first AC power supply 156 and the second AC power supply 157 are electrically connected to the conductive member of the base 1110 via the RF filter 159. The RF filter 159 removes high-frequency components (source RF signal, bias RF signal) and transmits DC components. The potential of the conductive member of the base 1110 is the self-bias voltage Vdc. As a result, the chuck power supply 15 applies an AC voltage offset by the self-bias voltage Vdc to the first chuck electrode 1111b1 and the second chuck electrode 1111b2. This allows the wafer chucking force to be constant.

[0198] A battery, an insulating transformer, or the like can be used to supply power to the first AC power supply 156 and the second AC power supply 157 that are floating in potential.

[0199] FIG. 37 is an example of a partially enlarged cross-sectional view of the substrate support 11 and a diagram showing the relationship with the potential.

[0200] Here, a voltage sensor 17 is provided to detect the potential of the base 1110, i.e., the self-bias voltage Vdc. The control unit 2 controls the DC power supply 158 based on the self-bias voltage Vdc detected by the voltage sensor 17. As a result, the chuck power supply 15 applies an AC voltage offset by the self-bias voltage Vdc to the first chuck electrode 1111b1 and the second chuck electrode 1111b2. This makes it possible to maintain a constant wafer chucking force.

[0201] The above-disclosed embodiments include, for example, the following aspects. (Supplementary Note 1) A plasma processing apparatus comprising: a plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and first to Nth (N is an integer of 2 or more) chuck electrodes disposed within the dielectric member below the ring support surface; an AC voltage generator configured to apply first to Nth AC voltages to the first to Nth chuck electrodes, respectively, the first to Nth AC voltages being phase-shifted with respect to one another; and a controller configured to execute an edge ring exchange sequence, the edge ring exchange sequence including the steps of: (a) changing the first to Nth AC voltages from an ON state to an OFF state; (b) removing a first edge ring from the ring support surface; (c) placing a second edge ring on the ring support surface; and (d) changing the first to Nth AC voltages from an OFF state to an ON state. (Supplementary Note 2) The plasma processing apparatus according to Supplementary Note 1, wherein the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode, and the AC voltage generator includes: an AC power supply configured to apply the first AC voltage to the first chuck electrode, and a phase adjuster electrically connected between the AC power supply and the second chuck electrode and configured to apply the second AC voltage, which is phase-shifted from the first AC voltage, to the second chuck electrode. (Supplementary Note 3) The plasma processing apparatus according to Supplementary Note 1, wherein the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode, and the AC voltage generator includes: a first AC power supply configured to apply the first AC voltage to the first chuck electrode, and a second AC power supply configured to apply the second AC voltage, which is phase-shifted from the first AC voltage, to the second chuck electrode. (Supplementary Note 4) The plasma processing apparatus according to any one of Supplementary Note 1 to Supplementary Note 3, wherein a phase difference between the first to Nth AC voltages is 1 / N×360°.(Supplementary Note 5) The plasma processing apparatus according to any one of Supplementary Notes 1 to 4, wherein the first to Nth chuck electrodes have a ring shape. (Supplementary Note 6) The plasma processing apparatus according to any one of Supplementary Notes 1 to 4, wherein the first to Nth chuck electrodes have a spiral shape or a nested structure. (Supplementary Note 7) The plasma processing apparatus according to any one of Supplementary Notes 1 to 6, wherein the first to Nth AC voltages have frequencies within a range of 0.01 Hz to 100 Hz. (Supplementary Note 8) A plasma processing apparatus comprising: a plasma generation unit configured to generate a plasma in the plasma processing chamber; an electrostatic chuck disposed in the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and first to Nth (N is an integer of 2 or more) chucking electrodes disposed within the dielectric member below the substrate support surface; an AC voltage generator electrically connected to the first to Nth chucking electrodes; and a controller configured to execute a substrate chucking sequence, the substrate chucking sequence including: (a) placing a substrate on the substrate support surface; (b) generating a first plasma in the plasma processing chamber; (c) applying first to Nth AC voltages to the first to Nth chuck electrodes, respectively, the first to Nth AC voltages having a first voltage level and a first frequency and being phase-shifted from one another; and (d) stopping generation of the first plasma. (e) changing the first to Nth AC voltages to second frequencies higher than the first frequency while maintaining the first voltage level, and (f) generating a second plasma in the plasma processing chamber. (Supplementary Note 9) The plasma processing apparatus according to Supplementary Note 8, wherein the plasma generating unit includes a source RF power generator configured to generate source RF power for plasma generation, and the source RF power has a first power level in the step (b), a zero power level in the step (d), and a second power level higher than the first power level in the step (f).(Supplementary Note 10) The plasma processing apparatus according to Supplementary Note 8, wherein the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode, and the AC voltage generator includes: an AC power supply configured to apply the first AC voltage to the first chuck electrode; and a phase adjuster electrically connected between the AC power supply and the second chuck electrode and configured to apply a second AC voltage, the second AC voltage being phase-shifted from the first AC voltage, to the second chuck electrode. (Supplementary Note 11) The plasma processing apparatus according to any one of Supplementary Notes 8 to 10, wherein a phase difference between the first to Nth AC voltages is 1 / N×360°. (Supplementary Note 12) The plasma processing apparatus according to any one of Supplementary Notes 8 to 11, wherein the first to Nth chuck electrodes have a circular or ring shape. (Supplementary Note 13) The plasma processing apparatus of any one of Supplementary Notes 8 to 11, wherein the first to Nth chuck electrodes have a spiral shape or a nested structure. (Supplementary Note 14) The plasma processing apparatus of any one of Supplementary Notes 8 to 13, wherein the first to Nth AC voltages have frequencies in a range of 0.01 Hz to 100 Hz. (Supplementary Note 15) The plasma processing apparatus of any one of Supplementary Notes 8 to 14, wherein the controller is configured to execute a substrate dechucking sequence, the substrate dechucking sequence including: (g) changing the first to Nth AC voltages to a third frequency greater than the second frequency while maintaining the first voltage level; (h) generating a third plasma in the plasma processing chamber; (i) initiating a decrease in the voltage levels of the first to Nth AC voltages; and (j) stopping generation of the third plasma. (Supplementary Note 16) The plasma processing apparatus according to Supplementary Note 15, wherein the step (j) is performed after the first to Nth AC voltages have been reduced to a zero voltage level. (Supplementary Note 17) The plasma processing apparatus according to Supplementary Note 15, wherein the step (j) is performed before the first to Nth AC voltages have been reduced to a zero voltage level.(Supplementary Note 18) A substrate attracting method for a plasma processing apparatus including: a plasma processing chamber; a plasma generating unit that generates plasma in the plasma processing chamber; and an electrostatic chuck disposed in the plasma processing chamber, the electrostatic chuck comprising a dielectric member having a substrate support surface and a ring support surface; two or more chuck electrodes disposed within the dielectric member below the substrate support surface; an AC voltage generator that applies AC voltages to the chuck electrodes; and a controller configured to be able to perform a process of electrostatically attracting a substrate attracted to the substrate support surface, the method comprising: placing a substrate on the substrate support surface; controlling the plasma generating unit to generate a first plasma in the plasma processing chamber; controlling the AC voltage generator to apply an AC voltage having a first voltage level and a first frequency to the chuck electrode; controlling the plasma generating unit to stop generation of the first plasma; and controlling the AC voltage generator to change the AC voltage applied to the chuck electrode to a second frequency higher than the first frequency while maintaining the first voltage level. controlling the plasma generating unit to generate a second plasma in the plasma processing chamber.

[0202] The embodiments disclosed above also include, for example, the following aspects: (Supplementary Note 1) A plasma processing apparatus comprising: a plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and a plurality of chuck electrodes disposed within the dielectric member below the ring support surface; and an AC voltage generator configured to apply AC voltages to the plurality of chuck electrodes, the AC voltages being phase-shifted from one another, wherein the plurality of chuck electrodes include one chuck electrode and another chuck electrode, the one chuck electrode having a plurality of arc portions, the other chuck electrodes having a plurality of arc portions, and the arc portions of the one chuck electrode and the other chuck electrodes being alternately arranged in a radial direction. (Supplementary Note 2) The plasma processing apparatus according to Supplementary Note 1, wherein one of the chuck electrodes has a first arcuate portion, a third arcuate portion, and a first connecting portion connecting the first arcuate portion and the third arcuate portion, and the other of the chuck electrodes has a second arcuate portion, a fourth arcuate portion, and a second connecting portion connecting the second arcuate portion and the fourth arcuate portion, the first arcuate portion, the second arcuate portion, the third arcuate portion, and the fourth arcuate portion being arranged in radial order from the outer periphery toward the center. (Supplementary Note 3) The plasma processing apparatus according to Supplementary Note 1 or Supplementary Note 2, wherein the plurality of chuck electrodes have a spiral shape or a nested structure.(Supplementary Note 4) The plasma processing apparatus according to any one of Supplementary Notes 1 to 3, further comprising: a control unit configured to execute an edge ring exchange sequence; the plurality of chuck electrodes include first to Nth chuck electrodes (N is an integer equal to or greater than 2) disposed below the ring support surface within the dielectric member; the AC voltage generator is configured to apply first to Nth AC voltages to the first to Nth chuck electrodes, respectively, and the first to Nth AC voltages are phase-shifted from each other; and the edge ring exchange sequence includes: (a) a step of changing the first to Nth AC voltages from an ON state to an OFF state; (b) a step of removing a first edge ring from the ring support surface; (c) a step of placing a second edge ring on the ring support surface; and (d) a step of changing the first to Nth AC voltages from an OFF state to an ON state. (Supplementary Note 5) The plasma processing apparatus according to Supplementary Note 4, wherein the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode, and the AC voltage generator includes: a power supply configured to apply the first AC voltage to the first chuck electrode, and a phase adjuster electrically connected between the power supply and the second chuck electrode and configured to apply the second AC voltage, which is phase-shifted from the first AC voltage, to the second chuck electrode. (Supplementary Note 6) The plasma processing apparatus according to Supplementary Note 4, wherein the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode, and the AC voltage generator includes: a first power supply configured to apply the first AC voltage to the first chuck electrode, and a second power supply configured to apply the second AC voltage, which is phase-shifted from the first AC voltage, to the second chuck electrode. (Supplementary Note 7) The plasma processing apparatus according to any one of Supplementary Notes 4 to 6, wherein a phase difference between the first to Nth AC voltages is 1 / N×360°. (Supplementary Note 8) The plasma processing apparatus according to any one of Supplementary Notes 4 to 7, wherein the first to Nth AC voltages have frequencies within a range of 0.01 Hz to 100 Hz. (Supplementary Note 9) The plasma processing apparatus according to any one of Supplementary Notes 4 to 8, wherein the first to Nth AC voltages are offset by a self-bias voltage.(Supplementary Note 10) A plasma processing apparatus comprising: a plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including: a dielectric member having a substrate support surface and a ring support surface; and first to Nth (N is an integer of 2 or more) chuck electrodes disposed within the dielectric member below the ring support surface; an AC voltage generator configured to apply first to Nth AC voltages to the first to Nth chuck electrodes, respectively, the first to Nth AC voltages being phase-shifted with respect to one another; and a controller configured to execute an edge ring exchange sequence, the edge ring exchange sequence including the steps of: (a) changing the first to Nth AC voltages from an ON state to an OFF state; (b) removing a first edge ring from the ring support surface; (c) placing a second edge ring on the ring support surface; and (d) changing the first to Nth AC voltages from an OFF state to an ON state. (Supplementary Note 11) The plasma processing apparatus according to Supplementary Note 9, wherein the first to Nth chuck electrodes have a ring shape.(Supplementary Note 12) A plasma processing apparatus comprising: a plasma generating unit configured to generate a plasma in the plasma processing chamber; an electrostatic chuck disposed in the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and first to Nth (N is an integer of 2 or more) chucking electrodes disposed within the dielectric member below the substrate support surface; an AC voltage generator electrically connected to the first to Nth chucking electrodes; and a controller configured to execute a substrate chucking sequence, the substrate chucking sequence including: (a) placing a substrate on the substrate support surface; (b) generating a first plasma in the plasma processing chamber; (c) applying first to Nth AC voltages to the first to Nth chuck electrodes, respectively, the first to Nth AC voltages having a first voltage level and a first frequency and being phase-shifted from one another; and (d) stopping generation of the first plasma. (e) changing the first to Nth AC voltages to a second frequency higher than the first frequency while maintaining the first voltage level, and (f) generating a second plasma in the plasma processing chamber. (Supplementary Note 13) The plasma processing apparatus according to Supplementary Note 12, wherein the plasma generating unit includes a source RF power generator configured to generate a source RF power for plasma generation, the source RF power having a first power level in the step (b), a zero power level in the step (d), and a second power level higher than the first power level in the step (f). (Supplementary Note 14) The plasma processing apparatus according to Supplementary Note 12, wherein the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode, and the AC voltage generator includes: a power supply configured to apply the first AC voltage to the first chuck electrode; and a phase adjuster electrically connected between the power supply and the second chuck electrode and configured to apply a second AC voltage, the second AC voltage being phase-shifted from the first AC voltage, to the second chuck electrode.(Supplementary Note 15) The plasma processing apparatus according to any one of Supplementary Notes 12 to 14, wherein a phase difference between the first to Nth AC voltages is 1 / N×360°. (Supplementary Note 16) The plasma processing apparatus according to any one of Supplementary Notes 12 to 15, wherein the first to Nth chuck electrodes have a circular or ring shape. (Supplementary Note 17) The plasma processing apparatus according to any one of Supplementary Notes 12 to 17, wherein the first to Nth chuck electrodes have a spiral shape or a nested structure. (Supplementary Note 18) The plasma processing apparatus according to any one of Supplementary Notes 12 to 18, wherein the first to Nth AC voltages have frequencies within a range of 0.01 Hz to 100 Hz. (Supplementary Note 19) The plasma processing apparatus of any one of Supplementary Notes 12 to 15, wherein the controller is configured to execute a substrate dechucking sequence, the substrate dechucking sequence including: (g) changing the first to Nth AC voltages to a third frequency higher than the second frequency while maintaining the first voltage level; (h) generating a third plasma in the plasma processing chamber; (i) starting to reduce the voltage levels of the first to Nth AC voltages; and (j) stopping generation of the third plasma. (Supplementary Note 20) The plasma processing apparatus of Supplementary Note 19, wherein step (j) is performed after the first to Nth AC voltages have reduced to zero voltage levels. (Supplementary Note 21) The plasma processing apparatus of Supplementary Note 19, wherein step (j) is performed before the first to Nth AC voltages have reduced to zero voltage levels.(Supplementary Note 22) A substrate attracting method for a plasma processing apparatus including: a plasma processing chamber; a plasma generating unit that generates plasma in the plasma processing chamber; and an electrostatic chuck disposed in the plasma processing chamber, the electrostatic chuck comprising a dielectric member having a substrate support surface and a ring support surface; two or more chuck electrodes disposed within the dielectric member below the substrate support surface; an AC voltage generator that applies AC voltages to the chuck electrodes; and a controller configured to be able to perform a process of electrostatically attracting a substrate attracted to the substrate support surface, the method comprising: placing a substrate on the substrate support surface; controlling the plasma generating unit to generate a first plasma in the plasma processing chamber; controlling the AC voltage generator to apply an AC voltage having a first voltage level and a first frequency to the chuck electrode; controlling the plasma generating unit to stop generation of the first plasma; and controlling the AC voltage generator to change the AC voltage applied to the chuck electrode to a second frequency higher than the first frequency while maintaining the first voltage level. controlling the plasma generating unit to generate a second plasma in the plasma processing chamber.

[0203] The present invention is not limited to the configurations described in the above embodiments, but may be combined with other elements, etc. These aspects can be changed without departing from the spirit of the present invention, and can be appropriately determined depending on the application form.

[0204] In addition, this application claims priority based on Japanese Patent Application No. 2022-212263 filed on December 28, 2022, and Japanese Patent Application No. 2023-150207 filed on September 15, 2023. The entire contents of these Japanese patent applications are incorporated herein by reference.

[0205] REFERENCE SIGNS LIST W substrate 1 plasma processing apparatus 10 plasma processing chamber 11 substrate support 111 main body 111a central region 111b annular region 112 ring assembly 112A edge ring 1110 base 1111 electrostatic chuck 1111a ceramic member (dielectric member) 1111b, 1111c electrostatic electrodes 1111b1 first chuck electrode 1111b2 second chuck electrode 1111b3 third chuck electrode 1111c1 first chuck electrode 1111c2 second chuck electrode 15, 16 chuck power supply 161 power supply 162 phase adjuster 163 first power supply 164 second power supply 165 third power supply 166 fourth power supply 301 first circular arc portion 302 second circular arc portion 303 Third arc portion 304 Fourth arc portion 311 First connecting portion 312 Second connecting portion

Claims

1. a plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and a plurality of chucking electrodes disposed within the dielectric member below the ring support surface; an AC voltage generator configured to apply AC voltages to the plurality of chuck electrodes, the AC voltages being phase-shifted from one another; the plurality of chuck electrodes include one chuck electrode and another chuck electrode, One of the chuck electrodes has a plurality of arcuate portions, The other chuck electrode has a plurality of arcuate portions, the arcuate portions of one of the chuck electrodes and the arcuate portions of the other of the chuck electrodes are alternately arranged in a radial direction. Plasma processing equipment.

2. one of the chuck electrodes has a first arcuate portion, a third arcuate portion, and a first connecting portion connecting the first arcuate portion and the third arcuate portion; the other chuck electrode has a second arcuate portion, a fourth arcuate portion, and a second connecting portion connecting the second arcuate portion and the fourth arcuate portion, The first arc portion, the second arc portion, the third arc portion, and the fourth arc portion are arranged in this order in the radial direction from the outer periphery side toward the center side, The plasma processing apparatus according to claim 1 .

3. The plurality of chuck electrodes have a spiral shape or a nested structure. The plasma processing apparatus according to claim 1 .

4. a controller configured to perform an edge ring exchange sequence; the plurality of chuck electrodes include first to Nth (N is an integer of 2 or more) chuck electrodes disposed below the ring support surface within the dielectric member; the AC voltage generator is configured to apply first to Nth AC voltages to the first to Nth chuck electrodes, respectively, the first to Nth AC voltages being phase-shifted with respect to each other; The edge ring exchange sequence includes: (a) changing the first to Nth AC voltages from an on state to an off state; (b) removing a first edge ring on the ring support surface; (c) placing a second edge ring on the ring support surface; (d) changing the first to Nth AC voltages from an off state to an on state; The plasma processing apparatus according to claim 1 .

5. the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode; The AC voltage generator a power supply configured to apply the first AC voltage to the first chuck electrode; a phase adjuster electrically connected between the power supply and the second chuck electrode and configured to apply the second AC voltage, which is phase-shifted from the first AC voltage, to the second chuck electrode. The plasma processing apparatus according to claim 4 .

6. the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode; The AC voltage generator a first power supply configured to apply the first AC voltage to the first chuck electrode; a second power supply configured to apply the second AC voltage, which is phase-shifted from the first AC voltage, to the second chuck electrode; The plasma processing apparatus according to claim 4 .

7. The phase difference between the first to Nth AC voltages is 1 / N×360°. The plasma processing apparatus according to claim 4 .

8. the first to Nth AC voltages have frequencies within a range of 0.01 Hz to 100 Hz; The plasma processing apparatus according to claim 4 .

9. the first to Nth AC voltages are offset by a self-bias voltage; The plasma processing apparatus according to claim 4 .

10. a plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including: a dielectric member having a substrate support surface and a ring support surface; and first to Nth (N is an integer of 2 or greater) chuck electrodes disposed within the dielectric member below the ring support surface; an AC voltage generator configured to apply first to Nth AC voltages to the first to Nth chuck electrodes, respectively, wherein the first to Nth AC voltages are phase-shifted with respect to one another; a controller configured to perform an edge ring exchange sequence; The edge ring exchange sequence includes: (a) changing the first to Nth AC voltages from an on state to an off state; (b) removing a first edge ring on the ring support surface; (c) placing a second edge ring on the ring support surface; (d) changing the first to Nth AC voltages from an off state to an on state; Plasma processing equipment.

11. the first to Nth chuck electrodes have a ring shape; The plasma processing apparatus according to claim 9 .

12. a plasma processing chamber; a plasma generating unit configured to generate a plasma in the plasma processing chamber; an electrostatic chuck disposed within the plasma processing chamber, the electrostatic chuck including a dielectric member having a substrate support surface and a ring support surface, and first to Nth (N is an integer of 2 or greater) chuck electrodes disposed within the dielectric member below the substrate support surface; an AC voltage generator electrically connected to the first to Nth chuck electrodes; a controller configured to execute a substrate chucking sequence; The substrate chucking sequence includes: (a) placing a substrate on the substrate support surface; (b) generating a first plasma in the plasma processing chamber; (c) applying first to Nth AC voltages to the first to Nth chuck electrodes, respectively, the first to Nth AC voltages having a first voltage level and a first frequency and being phase-shifted from one another; (d) ceasing generation of the first plasma; (e) changing the first to Nth AC voltages to a second frequency higher than the first frequency while maintaining the first voltage level; (f) generating a second plasma in the plasma processing chamber; Plasma processing equipment.

13. The plasma generating unit is a source RF power generator configured to generate source RF power for plasma generation; The source RF power is having a first power level in step (b); having a zero power level in step (d); In step (f), a second power level is set to be greater than the first power level. The plasma processing apparatus according to claim 12 .

14. the first to Nth chuck electrodes include a first chuck electrode and a second chuck electrode; The AC voltage generator a power supply configured to apply the first AC voltage to the first chuck electrode; a phase adjuster electrically connected between the power supply and the second chuck electrode and configured to apply to the second chuck electrode a second AC voltage that is phase-shifted from the first AC voltage. The plasma processing apparatus according to claim 12 .

15. The phase difference between the first to Nth AC voltages is 1 / N×360°. The plasma processing apparatus according to claim 12 .

16. The first to Nth chuck electrodes have a circular or ring shape. The plasma processing apparatus according to any one of claims 12 to 15.

17. the first to Nth chuck electrodes have a spiral shape or a nested structure; The plasma processing apparatus according to any one of claims 12 to 15.

18. the first to Nth AC voltages have frequencies within a range of 0.01 Hz to 100 Hz; The plasma processing apparatus according to any one of claims 12 to 15.

19. the controller is configured to perform a substrate dechucking sequence; the substrate dechucking sequence comprising: (g) changing the first to Nth AC voltages to a third frequency higher than the second frequency while maintaining the first voltage level; (h) generating a third plasma in the plasma processing chamber; (i) starting to decrease the voltage levels of the first to Nth AC voltages; (j) ceasing generation of the third plasma; The plasma processing apparatus according to any one of claims 12 to 15.

20. The step (j) performed after the first to Nth AC voltages have decreased to a zero voltage level; The plasma processing apparatus according to claim 19.

21. The step (j) before the first to Nth AC voltages are reduced to a zero voltage level. The plasma processing apparatus according to claim 19.

22. a plasma generating unit configured to generate plasma in the plasma processing chamber; an electrostatic chuck disposed in the plasma processing chamber, the electrostatic chuck comprising a dielectric member having a substrate support surface and a ring support surface; two or more chuck electrodes disposed within the dielectric member below the substrate support surface; an AC voltage generator configured to apply AC voltages to the chuck electrodes; and a control unit configured to perform a process of electrostatically attracting a substrate attracted to the substrate support surface, placing a substrate on the substrate support surface; controlling the plasma generating unit to generate a first plasma in the plasma processing chamber; controlling the AC voltage generator to apply an AC voltage having a first voltage level and a first frequency to the chuck electrode; controlling the plasma generating unit to stop generation of the first plasma; controlling the AC voltage generator to change the AC voltage applied to the chuck electrode to a second frequency greater than the first frequency while maintaining the first voltage level; and controlling the plasma generating unit to generate a second plasma in the plasma processing chamber. Substrate adsorption method.

23. the ring support surface of the electrostatic chuck has a diffusion groove for diffusing a heat transfer gas into a gap between the ring support surface and an annular member supported on the ring support surface, The diffusion groove is an annular groove portion provided concentrically with the electrostatic chuck; a radial groove portion communicating with the annular groove portion and provided in a radial direction of the electrostatic chuck from the annular groove portion, 13. The plasma processing apparatus according to claim 1, 10, or 12.

24. the diffusion groove has a plurality of the annular groove portions, The radial grooves communicate with the plurality of annular grooves. The plasma processing apparatus according to claim 23.

25. One end of the radial groove portion is provided radially inward of the annular groove portion, The other end of the radial groove portion is provided radially outward from the annular groove portion. The plasma processing apparatus according to claim 23.

26. one end of the radial groove portion is provided radially inward of an innermost annular groove portion of the plurality of annular groove portions, The other end of the radial groove portion is provided radially outward from the outermost inner annular groove portion of the plurality of annular groove portions. The plasma processing apparatus according to claim 24.

27. the electrostatic chuck has a plurality of electrodes that electrostatically attract the annular member, the annular groove portion is provided at a position where it does not overlap with an arc portion of one of the chuck electrodes and an arc portion of another of the chuck electrodes when the ring support surface is viewed in a plan view, In a plan view of the ring support surface, at least a portion of the radial grooves is provided at a position overlapping with the chuck electrode. The plasma processing apparatus according to claim 23.