Plasma processing apparatus

Abstract

Provided is a technique that makes it possible to suppress attenuation of the surface potential of a substrate in plasma processing. This plasma processing apparatus comprises: a first electrode disposed below a substrate support surface in an electrostatic chuck; a first switch; a first chuck power supply electrically connected to the first electrode via the first switch; a first voltage pulse generator electrically connected to the first electrode; and a control unit. The control unit is configured to control the first switch, the first chuck power supply, and the first voltage pulse generator to alternately apply a first reference voltage and a first pulse voltage to the first electrode during plasma processing of a substrate on the substrate support surface. The first reference voltage has a first chuck voltage level. The first pulse voltage has a first pulse voltage level. The absolute value of the first pulse voltage level is greater than the absolute value of the first chuck voltage level.

Description

Plasma processing equipment

[0001] SUMMARY OF THE INVENTION An exemplary embodiment of the present disclosure relates to a plasma processing apparatus.

[0002] In a plasma processing apparatus, a technique for reducing the influence of a phase difference between an electric bias for a substrate and an electric bias for an edge ring on plasma processing is disclosed in Japanese Patent Laid-Open No. 2003-222999.

[0003] Japanese Patent Application Laid-Open No. 2021-158134

[0004] The present disclosure provides a technique capable of suppressing the attenuation of the surface potential of a substrate during plasma processing.

[0005] In one exemplary embodiment of the present disclosure, a plasma processing apparatus includes: a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface; and a first electrode disposed within the electrostatic chuck below the substrate support surface; a first switch; a first chuck power supply electrically connected to the first electrode via the first switch; a first voltage pulse generator electrically connected to the first electrode; and a controller, wherein the controller is configured to control the first switch, the first chuck power supply, and the first voltage pulse generator to alternately apply a first reference voltage and a first pulse voltage to the first electrode during plasma processing of a substrate on the substrate support surface, wherein the first reference voltage has a first chuck voltage level, and the first pulse voltage has a first pulse voltage level, the absolute value of the first pulse voltage level being greater than the absolute value of the first chuck voltage level.

[0006] According to one exemplary embodiment of the present disclosure, a technique can be provided that can suppress attenuation of the surface potential of a substrate during plasma processing.

[0007] FIG. 1 is a diagram for explaining an example of the configuration of a plasma processing system. FIG. 2 is a diagram for explaining an example of the configuration of a plasma processing apparatus. FIG. 3 is a diagram for explaining an example of the configuration of a substrate support and a power supply in the first embodiment. FIG. 4 is a diagram for explaining an example of a first primary pulse voltage. FIG. 5 is a diagram for explaining an example of a second primary pulse voltage. FIG. 6 is a diagram for explaining an example of a control sequence of a first electrode, a first chuck power supply, and a first voltage pulse generator in the first embodiment. FIG. 7 is a diagram for explaining an example of a control sequence of a second electrode, a second chuck power supply, and a second voltage pulse generator in the first embodiment. FIG. 8 is a diagram for explaining that the attenuation amount of the surface potential Vw of the substrate is reduced according to the first embodiment. FIG. 9 is a diagram for explaining that the difference between the surface potential Vw of the substrate and the surface potential Vr of the edge ring is reduced according to the first embodiment. FIG. 10 is a diagram for explaining an example of the configuration of a substrate support and a power supply in the second embodiment. FIG. 11 is a diagram for explaining an example of the first pulse voltage. FIG. 12 is a diagram for explaining an example of the second pulse voltage. FIG. 13 is a diagram for explaining an example of the control sequence of the first electrode and the second power supply in the second embodiment. FIG. 14 is a diagram for explaining another example of the configuration of a substrate support and a power supply in the second embodiment. 1A and 1B are diagrams illustrating another example of the configuration of the second pulse voltage, a diagram illustrating another example of the configuration of the substrate support unit and the power supply, and a diagram illustrating an example of the pulse voltage PV1a and the pulse voltage PV1b.

[0008] Hereinafter, each embodiment of the present disclosure will be described.

[0009] In one exemplary embodiment, a plasma processing apparatus is provided, comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support having a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode disposed within the electrostatic chuck below the substrate support surface; a first switch; a first chuck power supply electrically connected to the first electrode via the first switch; a first voltage pulse generator electrically connected to the first electrode; and a controller, wherein the controller is configured to control the first switch, the first chuck power supply, and the first voltage pulse generator to alternately apply a first reference voltage and a first pulsed voltage to the first electrode during plasma processing of a substrate on the substrate support surface, wherein the first reference voltage has a first chuck voltage level, and the first pulsed voltage has a first pulsed voltage level, the absolute value of the first pulsed voltage level being greater than the absolute value of the first chuck voltage level.

[0010] In one exemplary embodiment, the first chucking voltage level and the first pulse voltage level have a negative polarity.

[0011] In one exemplary embodiment, the first chuck power supply is configured to generate a voltage having a first chuck voltage level, and the first voltage pulse generator is configured to generate a voltage having a voltage level corresponding to the difference between the first chuck voltage level and the first pulse voltage level.

[0012] In one exemplary embodiment, the first chucking voltage level is in the range of -1000V to -10000V and the first pulse voltage level is in the range of -10000V to -20000V.

[0013] In one exemplary embodiment, the electrostatic chuck further includes a ring support surface, the substrate support further includes at least one edge ring disposed on the ring support surface to surround the substrate on the substrate support surface, and a second electrode disposed within the electrostatic chuck below the ring support surface, and the plasma processing apparatus further includes a second switch, a second chuck power supply electrically connected to the second electrode via the second switch, and a second voltage pulse generator electrically connected to the second electrode, and the controller is configured to control the second switch, the second chuck power supply, and the second voltage pulse generator to alternately apply a second reference voltage and a second pulsed voltage to the second electrode during plasma processing of the substrate on the substrate support surface, the second reference voltage having a second chucking voltage level, the second pulsed voltage having a second pulsed voltage level, and the absolute value of the second pulsed voltage level being greater than the absolute value of the second chucking voltage level.

[0014] In one exemplary embodiment, the second chucking voltage level and the second pulse voltage level have a negative polarity.

[0015] In one exemplary embodiment, the second chuck power supply is configured to generate a voltage having a second chuck voltage level, and the second voltage pulse generator is configured to generate a voltage having a voltage level corresponding to the difference between the second chuck voltage level and the second pulse voltage level.

[0016] In one exemplary embodiment, the second chucking voltage level is equal to the first chucking voltage level.

[0017] In one exemplary embodiment, the absolute value of the second pulse voltage level is greater than the absolute value of the first pulse voltage level.

[0018] In one exemplary embodiment, the second chucking voltage level is in the range of -1000V to -10000V and the second pulse voltage level is in the range of -10000V to -20000V.

[0019] In one exemplary embodiment, a plasma processing apparatus is provided, comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode disposed within the electrostatic chuck below the substrate support surface; and a first voltage pulse generator electrically connected to the first electrode and configured to generate a first voltage pulse signal, the first voltage pulse signal having an alternating first reference voltage and a first pulse voltage, the first reference voltage having a first chuck voltage level, the first pulse voltage having a first pulse voltage level, and the absolute value of the first pulse voltage level being greater than the absolute value of the first chuck voltage level.

[0020] In one exemplary embodiment, the first chucking voltage level and the first pulse voltage level have a negative polarity.

[0021] In one exemplary embodiment, the first chucking voltage level is in the range of -1000V to -10000V and the first pulse voltage level is in the range of -10000V to -20000V.

[0022] In one exemplary embodiment, the electrostatic chuck further includes a ring support surface, the substrate support further includes at least one edge ring disposed on the ring support surface to surround the substrate on the substrate support surface, and a second electrode disposed within the electrostatic chuck below the ring support surface, and the plasma processing apparatus further includes a second voltage pulse generator electrically connected to the second electrode and configured to generate a second voltage pulse signal, the second voltage pulse signal having an alternating second reference voltage and a second pulse voltage, the second reference voltage having a second chuck voltage level, the second pulse voltage having a second pulse voltage level, and the absolute value of the second pulse voltage level being greater than the absolute value of the second chuck voltage level.

[0023] In one exemplary embodiment, the second chucking voltage level and the second pulse voltage level have a negative polarity.

[0024] In one exemplary embodiment, the second chucking voltage level is equal to the first chucking voltage level.

[0025] In one exemplary embodiment, the absolute value of the second pulse voltage level is greater than the absolute value of the first pulse voltage level.

[0026] In one exemplary embodiment, the second chucking voltage level is in the range of -1000V to -10000V and the second pulse voltage level is in the range of -10000V to -20000V.

[0027] In one exemplary embodiment, a plasma processing apparatus is provided, comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode disposed within the electrostatic chuck below the substrate support surface; and a first voltage pulse generator electrically connected to the first electrode and configured to generate a first pulsed voltage having alternating first and second negative voltage levels to provide bias energy to a substrate on the substrate support surface while maintaining a chucked state of the substrate to the substrate support surface, the absolute value of the first negative voltage level being greater than the absolute value of the second negative voltage level.

[0028] In one exemplary embodiment, the first pulse voltage has a third negative voltage level before the repetition of the first negative voltage level and the second negative voltage level, and the absolute value of the third negative voltage level is less than the absolute value of the first negative voltage level and greater than the absolute value of the second negative voltage level.

[0029] In one exemplary embodiment, the first negative voltage level is in the range of -3000V to -15000V.

[0030] In one exemplary embodiment, the second negative voltage level is in the range of -500V to -6000V.

[0031] In one exemplary embodiment, the third negative voltage level is in the range of -1000V to -10000V.

[0032] In one exemplary embodiment, the distance between the substrate support surface and the first electrode is 0.3 mm or less.

[0033] In one exemplary embodiment, a plasma processing apparatus is provided, comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support having a base, an electrostatic chuck disposed on the base and having a substrate support surface; and a first electrode and a second electrode disposed within the electrostatic chuck below the substrate support surface; a first voltage pulse generator electrically connected to the first electrode and configured to generate a first pulsed voltage; and a second voltage pulse generator electrically connected to the second electrode and configured to generate a second pulsed voltage, wherein the first pulsed voltage has a first negative voltage level and a zero voltage level during alternating first and second periods, respectively, and the second pulsed voltage has a zero voltage level and a second negative voltage level during the first and second periods, respectively.

[0034] In one exemplary embodiment, the first pulse voltage has a third negative voltage level before the repetition of the first period and the second period, and the absolute value of the third negative voltage level is less than the absolute values ​​of the first negative voltage level and the second negative voltage level.

[0035] In one exemplary embodiment, the first voltage pulse generator and the second voltage pulse generator are integrated.

[0036] In one exemplary embodiment, the first negative voltage level and the second negative voltage level are in the range of −3000V to −15000V.

[0037] In one exemplary embodiment, the first negative voltage level is equal to the second negative voltage level.

[0038] In one exemplary embodiment, the third negative voltage level is in the range of -1000V to -10000V.

[0039] In one exemplary embodiment, the distance between the substrate support surface and the first electrode is 0.3 mm or less.

[0040] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or similar elements are designated by the same reference numerals, and redundant explanations will be omitted. Unless otherwise specified, the positional relationships, such as up, down, left, and right, will be described based on the positional relationships shown in the drawings. The dimensional ratios in the drawings do not represent actual ratios, and the actual ratios are not limited to the ratios shown in the drawings.

[0041] First Embodiment Example of a Plasma Processing System FIG. 1 is a diagram illustrating an example of the configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0042] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma generated in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0043] 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).

[0044] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0045] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10 (also simply referred to as the "chamber"), a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0046] 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.

[0047] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32, which will be described later, may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Furthermore, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0048] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of a conductive or insulating material.

[0049] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow passage 1110a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 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 heat transfer gas supply configured to supply a heat transfer gas to a gap between the backside of the substrate W and the central region 111a.

[0050] 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.

[0051] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0052] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0053] 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.

[0054] 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 100 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.

[0055] 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 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.

[0056] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof 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.

[0057] 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.

[0058] 3, in the first embodiment, the plasma processing apparatus 1 includes a first electrode 200, a first switch 201, a first chuck power supply 202, a first power supply 203, a first voltage pulse generator 204, a second electrode 210, a second switch 211, a second chuck power supply 212, a second power supply 213, and a second voltage pulse generator 214. The first power supply 203, the first voltage pulse generator 204, the second power supply 213, and the second voltage pulse generator 214 may be included in the DC power supply 32 in FIG.

[0059] The first electrode 200 shown in FIG. 3 serves as both a substrate chuck electrode and a substrate bias electrode. The first electrode 200 is disposed below the substrate support surface (central region 111a) in the electrostatic chuck 1111. In one embodiment, the first electrode 200 may have a circular shape. However, when the substrate chuck electrode and the substrate bias electrode are provided independently, the substrate bias electrode needs to be disposed further below the substrate chuck electrode to ensure a sufficient voltage resistance. In contrast, the first electrode 200 shown in FIG. 3 serves as both a substrate chuck electrode and a substrate bias electrode. Therefore, the distance between the substrate support surface (central region 111a) and the first electrode 200 can be reduced compared to when the substrate chuck electrode and the substrate bias electrode are provided separately in the electrostatic chuck 1111. When the distance between the substrate support surface (central region 111a) and the first electrode 200 is reduced, the capacitance of the capacitor from the electrode to the substrate tends to increase. As a result, when a pulse voltage is applied during plasma processing, the surface potential of the substrate can be prevented from decaying. In one embodiment, the distance between the substrate support surface (central region 111 a) and the first electrode 200 is 0.3 mm or less.

[0060] The first chuck power supply 202 is electrically connected to the first electrode 200 via the first switch 201. The first chuck power supply 202 may be a DC power supply. The first chuck power supply 202 is configured to apply a first reference voltage BV1 to the first electrode 200. The first reference voltage BV1 has a first chuck voltage level (vc1). The first chuck voltage level (vc1) may have negative polarity. The first chuck voltage level (vc1) may be in the range of −1000 V to −10000 V. When the first reference voltage BV1 is applied from the first chuck power supply 202 to the first electrode 200, an electrostatic attractive force (Coulomb force) is generated between the first electrode 200 and the substrate W. The substrate W is attracted to the electrostatic chuck 1111 by the electrostatic attractive force and is adsorbed and held on the substrate support surface.

[0061] The first power supply 203 is configured to generate a first DC voltage DCV1. The first DC voltage DCV1 has a first DC voltage level (v1). The first DC voltage level (v1) may be negative. The first power supply 203 is electrically connected to the first voltage pulse generator 204. The first power supply 203 can supply a signal of the generated first DC voltage DCV1 to the first voltage pulse generator 204.

[0062] The first voltage pulse generator 204 is configured to generate a plurality of first primary pulse voltage PPV1 signals from the first DC voltage DCV1 signal. Each of the plurality of first primary pulse voltages PPV1 has a first primary pulse voltage level (v2). The first voltage pulse generator 204 may be capable of supplying the first DC voltage DCV1 signal to the second voltage pulse generator 214.

[0063] 4, in one embodiment, each of the plurality of first primary pulse voltages PPV1 includes a plurality of first voltage pulses P1(n) (n is an integer). The plurality of first voltage pulses P1(n) includes a first primary pulse voltage level (v2) and a reference voltage level (v ｒｅｆ１ ) and a reference voltage level (v ｒｅｆ１ The absolute value of the reference voltage level (v) is less than the absolute value of the first primary pulse voltage level (v2). In one embodiment, the first primary pulse voltage level (v2) has a negative polarity. ｒｅｆ１ ) has a zero voltage level. As shown in FIG. 4 , in one embodiment, each of the plurality of first voltage pulses P1(n) may have a rectangular pulse waveform. Note that each of the plurality of first voltage pulses P1(n) may have various pulse waveforms other than rectangular, such as trapezoidal, triangular, or a combination thereof.

[0064] 3 , the first voltage pulse generator 204 is electrically connected to the first electrode 200. The first voltage pulse generator 204 may be electrically connected to the first electrode 200 via a low-pass filter 270, a switch 271, or the like. The first voltage pulse generator 204 can apply the generated multiple first primary pulse voltages PPV1 to the first electrode 200. By applying the multiple first primary pulse voltages PPV1 to the first electrode 200, ion components in the plasma formed on the substrate on the substrate support surface can be attracted to the substrate W.

[0065] The second electrode 210 serves as both a ring chuck electrode and a ring bias electrode. The second electrode 210 is disposed below a ring support surface (annular region 111b) within the electrostatic chuck 1111. The ring support surface supports at least one edge ring 250 of the ring assembly 112. In one embodiment, the second electrode 210 may have a ring shape with a width in the radial direction. In one embodiment, the second electrode 210 may have an inner diameter smaller than the outer diameter of the first electrode 200 and an outer diameter larger than the outer diameter of the first electrode 200. A portion of the second electrode 210 may vertically overlap a portion of the first electrode 200.

[0066] The second chuck power supply 212 is electrically connected to the second electrode 210 via the second switch 211. The second chuck power supply 212 may be a DC power supply. The second chuck power supply 212 is configured to apply a second reference voltage BV2 to the second electrode 210. The second reference voltage BV2 has a second chuck voltage level (vc2). The second chuck voltage level (vc2) may have negative polarity. The second chuck voltage level (vc2) may be in the range of −1000 V to −10000 V. The second chuck voltage level (vc2) may be equal to the first chuck voltage level (vc1). When the second reference voltage BV2 is applied from the second chuck power supply 212 to the second electrode 210, an electrostatic attraction force (Coulomb force) is generated between the second electrode 210 and the edge ring 250. The edge ring 250 is attracted to the electrostatic chuck 1111 by the electrostatic force and is held by suction on the ring support surface.

[0067] The second power supply 213 is configured to generate a second DC voltage DCV2. The second DC voltage DCV2 has a second DC voltage level (v3). The second DC voltage level (v3) may be negative. The second power supply 213 is electrically connected to the second voltage pulse generator 214. The second power supply 213 can supply a signal of the generated second DC voltage DCV2 to the second voltage pulse generator 214.

[0068] The second voltage pulse generator 214 is configured to generate a plurality of second primary pulse voltage PPV2 signals from the second DC voltage DCV2 signal and the first DC voltage DCV1 signal supplied from the second voltage pulse generator 214. Each of the plurality of second primary pulse voltages PPV2 has a second primary pulse voltage level (v4). The second primary pulse voltage level (v4) may be generated by adding the second DC voltage level (v3) and the first DC voltage level (v1). Note that the second voltage pulse generator 214 may be configured to generate a plurality of second primary pulse voltage PPV2 signals from the second DC voltage DCV2 signal.

[0069] 5, in one embodiment, each of the plurality of second primary pulse voltages PPV2 includes a plurality of second voltage pulses P2(n) (n is an integer). The plurality of second voltage pulses P2(n) includes a second primary pulse voltage level (v4) and a reference voltage level (v ｒｅｆ２ ) and a reference voltage level (v ｒｅｆ２ The absolute value of the reference voltage level (v) is less than the absolute value of the second primary pulse voltage level (v4). In one embodiment, the second primary pulse voltage level (v4) has a negative polarity. ｒｅｆ２ ) has a zero voltage level. As shown in FIG. 5 , in one embodiment, each of the plurality of second voltage pulses P2(n) may have a rectangular pulse waveform. Note that each of the plurality of second voltage pulses P2(n) may have various pulse waveforms other than rectangular, such as trapezoidal, triangular, or a combination thereof.

[0070] 3 , the second voltage pulse generator 214 is electrically connected to the second electrode 210. The second voltage pulse generator 214 may be electrically connected to the second electrode 210 via a low-pass filter 280, a switch 281, or the like. The second voltage pulse generator 214 can apply the generated second primary pulse voltages PPV2 to the second electrode 210. By applying the second primary pulse voltages PPV2 to the second electrode 210, ion components in the plasma formed on the edge portion of the substrate W can be attracted to the edge portion (edge ​​ring 250) of the substrate W.

[0071] <Example of Plasma Processing Method> The plasma processing method performed in the plasma processing apparatus 1 includes an etching process that uses plasma to etch a film on the substrate W. In one embodiment, the plasma processing method is executed by the control unit 2 in the plasma processing apparatus 1.

[0072] First, the substrate W is carried into the chamber 10 by the transport arm, placed on the substrate support 11 by the lifter, and held by suction on the substrate support 11 as shown in FIG.

[0073] Next, plasma is generated in the plasma processing space 10s by the plasma generation unit 12. First, a processing gas is supplied to the shower head 13 by the gas supply unit 20, and then supplied from the shower head 13 to the plasma processing space 10s. The processing gas supplied at this time includes a gas that generates activated species necessary for etching the substrate W.

[0074] A source RF signal is supplied to the upper electrode and / or the lower electrode from an RF power supply 31. A bias DC signal is supplied to the lower electrode from a DC power supply 32 (a first power supply 203, a first voltage pulse generator 204, a second power supply 213, and a second voltage pulse generator 214). The atmosphere in the plasma processing space 10s is exhausted from a gas exhaust port 10e, and the inside of the plasma processing space 10s is depressurized. Plasma is generated from the processing gas on the substrate support 11 in the plasma processing space 10s, and the substrate W is etched.

[0075] <Example of Control Sequence> Fig. 6 is a diagram for explaining an example of a control sequence by the control unit 2 for the first electrode 200, the first chuck power supply 202, and the first voltage pulse generator 204 in the plasma processing apparatus 1. Fig. 7 is a diagram for explaining an example of a control sequence by the control unit 2 for the second electrode 210, the second chuck power supply 212, and the second voltage pulse generator 214 in the plasma processing apparatus 1. The control sequence may have first to seventh periods T1 to T7.

[0076] During the first period T1, the lifter is raised and lowered, and the substrate is placed on the substrate support surface of the electrostatic chuck 1111. At this time, the first switch 201 is OFF, and as shown in FIG. 6, the application of the first reference voltage BV1 from the first chuck power supply 202 to the first electrode 200 is stopped. Furthermore, the application of the first primary pulse voltage PPV1 from the first voltage pulse generator 204 to the first electrode 200 is stopped. As a result, the voltage of the first electrode 200 becomes 0 V. Furthermore, at this time, the second switch 211 is ON, and as shown in FIG. 7, the second reference voltage BV2 is applied to the second electrode 210 from the second chuck power supply 212. Furthermore, the application of the second primary pulse voltage PPV2 from the second voltage pulse generator 214 to the second electrode 210 is stopped. As a result, the voltage of the second electrode 210 becomes the second chuck voltage level (vc2) of the second reference voltage BV2. During the first period T1, gas is supplied from the shower head 13 into the chamber 10, and the pressure in the chamber 10 stabilizes.

[0077] During the second period T2, a source RF signal is supplied to the upper electrode and / or the lower electrode, temporarily generating plasma in the chamber 10. During the second period T2, the first switch 201 is turned ON, and as shown in FIG. 6 , the first chuck power supply 202 applies a first reference voltage BV1 to the first electrode 200. Furthermore, the application of the first primary pulse voltage PPV1 from the first voltage pulse generator 204 to the first electrode 200 is stopped. As a result, the voltage of the first electrode 200 becomes the first chucking voltage level (vc1) of the first reference voltage BV1. Furthermore, as shown in FIG. 7 , the voltage of the second electrode 210 is maintained at the second chucking voltage level (vc2) of the second reference voltage BV2. During the second period T2, charge is supplied from the plasma to the substrate support surface, the substrate W, the link support surface, and the edge ring 250.

[0078] In the third period T3, the supply of the source RF signal to the upper electrode and / or the lower electrode is stopped, and the plasma is extinguished in the chamber 10. For example, a heat transfer gas is supplied to the gap between the back surface of the substrate W and the central region 111 a to adjust the temperature of the substrate on the substrate support surface.

[0079] In the fourth period T4, a plasma process is performed by supplying a source RF signal to the upper electrode and / or the lower electrode, as in the plasma process method described above.

[0080] 6 , a first reference voltage BV1 and a first pulse voltage PV1 are alternately applied to the first electrode 200. The first pulse voltage PV1 is formed by superimposing a plurality of first primary pulse voltages PPV1 applied from a first voltage pulse generator 204 and a first reference voltage BV1 applied from a first chuck power supply 202. When the first pulse voltage PV1 is applied, the voltage of the first electrode 200 becomes a first pulse voltage level (v5 (=vc1+v2)) obtained by adding together a first chucking voltage level (vc1) of the first reference voltage BV1 and a first primary pulse voltage level (v2) of the first primary pulse voltage PPV1. That is, the first voltage pulse generator 204 generates a voltage (first primary pulse voltage PPV1) having a voltage level corresponding to the difference between the first chuck voltage level (vc1) and the first pulse voltage level (v5). When only the first reference voltage BV1 is applied, the voltage of the first electrode 200 is the first chuck voltage level (vc1). As a result, a voltage of the first chuck voltage level (vc1) and a voltage of the first pulse voltage level (v5 (=vc1+v2)) are alternately applied to the first electrode 200. This allows a bias DC signal to be supplied to the electrostatic chuck 1111 while attracting the substrate W to the electrostatic chuck 1111 during plasma processing. In one embodiment, the first pulse voltage level (v5) has negative polarity and may be within a range of −10,000 V to −20,000 V.

[0081] 7 , a second reference voltage BV2 and a second pulse voltage PV2 are alternately applied to the second electrode 210. The second pulse voltage PV2 is formed by superimposing a plurality of second primary pulse voltages PPV2 applied from a second voltage pulse generator 214 and a second reference voltage BV2 applied from a second chuck power supply 212. When the second pulse voltage PV2 is applied, the voltage of the second electrode 210 becomes a second pulse voltage level (v6 (= vc2 + v4)) obtained by adding together a second chucking voltage level (vc2) of the second reference voltage BV2 and a second primary pulse voltage level (v4) of the second primary pulse voltage PPV2. That is, the second voltage pulse generator 214 generates a voltage (second primary pulse voltage PPV2) having a voltage level corresponding to the difference between the second chuck voltage level (vc2) and the second pulse voltage level (v6). When only the second reference voltage BV2 is applied, the voltage of the second electrode 210 is the second chuck voltage level (vc2). As a result, a voltage of the second chuck voltage level (vc2) and a voltage of the second pulse voltage level (v6 (=vc2+v4)) are alternately applied to the second electrode 210. This allows a bias DC signal to be supplied to the outer periphery of the electrostatic chuck 1111 while attracting the edge ring 250 to the electrostatic chuck 1111 during plasma processing. Note that, in one embodiment, the second pulse voltage level (v6) has negative polarity and may be within a range of −10,000 V to −20,000 V. The absolute value of the second pulse voltage level (v6) may be greater than the absolute value of the first pulse voltage level (v5).

[0082] During the fifth period T5, the supply of the source RF signal to the upper electrode and / or the lower electrode is stopped. The supply of the heat transfer gas to the gap between the back surface of the substrate W and the central region 111a is also stopped. At this time, as shown in FIG. 6 , the application of the first primary pulse voltage PPV1 from the first voltage pulse generator 204 to the first electrode 200 is stopped, causing the voltage of the first electrode 200 to reach the first chucking voltage level (vc1) of the first reference voltage BV1. At this time, as shown in FIG. 7 , the application of the second primary pulse voltage PPV2 from the second voltage pulse generator 214 to the second electrode 210 is stopped, causing the voltage of the second electrode 210 to reach the second chucking voltage level (vc2) of the second reference voltage BV2.

[0083] During the sixth period T6, a source RF signal is supplied to the upper electrode and / or the lower electrode, temporarily generating plasma in the chamber 10. In the middle of the sixth period T6, the first switch 201 is turned OFF, and as shown in FIG. 6, the application of the first reference voltage BV1 from the first chuck power supply 202 to the first electrode 200 is stopped. As a result, the voltage of the first electrode 200 becomes 0 V. Furthermore, as shown in FIG. 7, the voltage of the second electrode 210 is maintained at the second chucking voltage level (vc2) of the second reference voltage BV2.

[0084] In a seventh period T7, the lifter is raised and lowered, and the substrate is transported from the substrate support surface to the outside of the chamber 10. Thereafter, the first switch 201 is temporarily turned ON, and as shown in Fig. 6, a positive voltage is temporarily applied to the first electrode 200, thereby decharging the electrostatic chuck 1111. At this time, as shown in Fig. 7, the voltage of the second electrode 210 is maintained at the second chucking voltage level (vc2) of the second reference voltage BV2.

[0085] According to this exemplary embodiment, a plasma processing apparatus 1 includes a first electrode 200 disposed below a substrate support surface within an electrostatic chuck 1111, a first switch 201, a first chuck power supply 202 electrically connected to the first electrode 200, a first voltage pulse generator 204 electrically connected to the first electrode 200, and a controller 2, wherein the controller 2 is configured to control the first switch 201, the first chuck power supply 202, and the first voltage pulse generator 204 to alternately apply a first reference voltage BV1 and a first pulse voltage PV1 to the first electrode 200 during plasma processing of a substrate on the substrate support surface. The first reference voltage BV1 has a first chucking voltage level (vc1), and the first pulse voltage PV1 has a first pulse voltage level (v5), the absolute value of which is greater than the absolute value of the first chucking voltage level (vc1). According to this embodiment, by using a single first electrode 200 to increase the capacitance of the capacitor from the electrode to the substrate and applying an appropriate voltage to the first electrode 200, it is possible to suppress attenuation of the surface potential of the substrate during plasma processing. That is, as shown in FIG. 8 , when a pulse voltage is applied during plasma processing, attenuation of the surface potential Vw of the substrate is suppressed. As a result, plasma processing of the substrate is performed stably.

[0086] According to this exemplary embodiment, the plasma processing apparatus 1 further includes an edge ring 250, a second electrode 210 disposed below the ring support surface within the electrostatic chuck 1111, a second switch 211, a second chuck power supply 212 electrically connected to the second electrode 210, and a second voltage pulse generator 214 electrically connected to the second electrode 210, and the control unit 2 is configured to control the second switch 211, the second chuck power supply 212, and the second voltage pulse generator 214 so as to alternately apply a second reference voltage BV2 and a second pulse voltage PV2 to the second electrode 210 during plasma processing of a substrate on the substrate support surface. The second reference voltage BV2 has a second chucking voltage level (vc2), and the second pulse voltage PV2 has a second pulse voltage level (v6), the absolute value of which is greater than the absolute value of the second chucking voltage level (vc2). According to this embodiment, by using a single second electrode 210 to increase the capacitance of the capacitor from the electrode to the edge ring and applying an appropriate voltage to the second electrode 210, it is possible to suppress attenuation of the surface potential of the edge ring during plasma processing. Furthermore, it is possible to reduce the difference between the surface potential of the substrate and the surface potential of the edge ring during plasma processing. That is, as shown in FIG. 9 , when a pulse voltage is applied during plasma processing, the difference between the surface potential Vw of the substrate and the surface potential Vr of the edge ring is reduced. As a result, the angle of incidence of ions at the outer periphery of the substrate approaches perpendicularity, thereby ensuring proper plasma processing at the outer periphery of the substrate.

[0087] 10 , in the second embodiment, a plasma processing apparatus 1 includes a first electrode 200, a first power supply 203, a first voltage pulse generator 204, a second electrode 210, a second power supply 213, and a second voltage pulse generator 214. The plasma processing apparatus 1 of the second embodiment differs from the first embodiment in that it does not include a first switch 201, a first chuck power supply 202, a second switch 211, or a second chuck power supply 212.

[0088] The first power supply 203 is configured to generate a plurality of first DC voltages DCV1(n) (n is an integer). Each of the plurality of first DC voltages DCV1(n) has a first DC voltage level (v1(n) (n is an integer)). The plurality of first DC voltage levels (v1(n)) may include a first chuck voltage level (vc1) and a first pulse voltage level (v5). The plurality of first DC voltage levels (v1(n)) may include a first DC voltage level (v1). Each of the first DC voltage levels (v1(n)) may have a negative polarity. The first power supply 203 is electrically connected to the first voltage pulse generator 204. The first power supply 203 can supply signals of the generated plurality of first DC voltages DCV1(n) to the first voltage pulse generator 204.

[0089] The first voltage pulse generator 204 is configured to generate a first voltage pulse signal PS1 from a plurality of first DC voltage DCV1(n) signals. The first voltage pulse signal PS1 includes a first reference voltage BV1 and a first pulse voltage PV1 that are alternately repeated. The first reference voltage BV1 has a first chuck voltage level (vc1). The first pulse voltage PV1 has a first pulse voltage level (v5). The first pulse voltage level (v5) may be generated by adding the first chuck voltage level (vc1) and the first DC voltage level (v1). The first chuck voltage level (vc1) is a voltage level required to attract and hold a substrate on the substrate support surface. The first pulse voltage level (v5) is a voltage level required to attract and hold a substrate on the substrate support surface and to attract ion components in plasma formed above the substrate on the substrate support surface to the substrate W. In one embodiment, the first chuck voltage level (vc1) and the first pulse voltage level (v5) may have negative polarity. The first chuck voltage level (vc1) may be in the range of −1000 V to −10,000 V, and the first pulse voltage level (v5) may be in the range of −10,000 V to −20,000 V. The first voltage pulse generator 204 may be capable of providing a plurality of first DC voltage DCV1(n) signals to the second voltage pulse generator 214.

[0090] 11, in one embodiment, each of the plurality of first pulse voltages PV1 includes a plurality of first voltage pulses P1(n) (n is an integer). The plurality of first voltage pulses P1(n) includes a first pulse voltage level (v5) and a reference voltage level (v ｒｅｆ１ ) and a reference voltage level (v ｒｅｆ１ ) is the voltage level required to attract and hold the substrate to the substrate support surface. In one embodiment, the reference voltage level (v ｒｅｆ１ ) is equal to the first chucking voltage level (vc1). As shown in FIG. 11 , in one embodiment, each of the plurality of first voltage pulses P1(n) may have a rectangular pulse waveform. Note that each of the plurality of first voltage pulses P1(n) may have various pulse waveforms other than rectangular, such as trapezoidal, triangular, or a combination thereof.

[0091] The first voltage pulse generator 204 shown in FIG. 10 can supply the generated first voltage pulse signal PS1 to the first electrode 200.

[0092] The second power supply 213 is configured to generate a plurality of second DC voltages DCV2(n) (n is an integer). Each of the plurality of second DC voltages DCV2(n) has a second DC voltage level (v3(n) (n is an integer)). The plurality of second DC voltage levels (v2(n)) may include a second chuck voltage level (vc2) and a second pulse voltage level (v6). The plurality of second DC voltage levels (v2(n)) may include a second DC voltage level (v3). Each of the second DC voltage levels (v3(n)) may have a negative polarity. The second power supply 213 is electrically connected to the second voltage pulse generator 214. The second power supply 213 can supply signals of the generated plurality of second DC voltages DCV2(n) to the second voltage pulse generator 214.

[0093] The second voltage pulse generator 214 is configured to generate a second voltage pulse signal PS2 from a plurality of second DC voltage DCV2(n) signals and a plurality of first DC voltage DCV1(n) signals supplied from the first voltage pulse generator 204. The second voltage pulse signal PS2 includes a second reference voltage BV2 and a second pulse voltage PV2 that are alternately repeated. The second reference voltage BV2 has a second chucking voltage level (vc2). The second pulse voltage PV2 has a second pulse voltage level (v6). The second pulse voltage level (v6) may be generated by adding the second chucking voltage level (vc2), the second DC voltage level (v3), and the first DC voltage level (v1). The second chucking voltage level (vc2) is a voltage level required to attract and hold the edge ring 250 to the ring support surface. The second pulse voltage level (v6) is a voltage level required to attract and hold the edge ring 250 to the ring support surface and to attract ion components in the plasma to the outer periphery of the substrate W (the edge ring 250). In one embodiment, the second chuck voltage level (vc2) and the second pulse voltage level (v6) may have negative polarity. The second chuck voltage level (vc2) may be in the range of −1000 V to −10,000 V, and the second pulse voltage level (v6) may be in the range of −10,000 V to −20,000 V. In one embodiment, the second chuck voltage level (vc2) may be equal to the first chuck voltage level (vc1). The absolute value of the second pulse voltage level (v6) may be greater than the absolute value of the first pulse voltage level (v5). The second voltage pulse generator 214 may be configured to generate the second voltage pulse signal PS2 from a plurality of second DC voltage DCV2(n) signals.

[0094] 12, in one embodiment, each of the plurality of second pulse voltages PV2 includes a plurality of second voltage pulses P2(n) (n is an integer). The plurality of second voltage pulses P2(n) includes a second pulse voltage level (v6) and a reference voltage level (v ｒｅｆ２ ) and a reference voltage level (v ｒｅｆ２) is the voltage level required to attract and hold the substrate to the substrate support surface. In one embodiment, the reference voltage level (v ｒｅｆ２ ) is equal to the second chucking voltage level (vc2). As shown in FIG. 12 , in one embodiment, each of the plurality of second voltage pulses P2(n) may have a rectangular pulse waveform. Note that each of the plurality of second voltage pulses P2(n) may have various pulse waveforms other than rectangular, such as trapezoidal, triangular, or a combination thereof.

[0095] The second voltage pulse generator 214 shown in FIG. 10 can apply the generated second voltage pulse signal PS2 to the second electrode 210.

[0096] Other configurations of the plasma processing apparatus 1 in the second embodiment may be similar to those in the first embodiment.

[0097] 13 is a diagram illustrating an example of a control sequence for the first electrode 200 and the second electrode 210 by the control unit 2 in the second embodiment. The control sequence may have first to seventh periods T1 to T7.

[0098] During the first period T1, the lifter is raised and lowered, and the substrate is placed on the substrate support surface of the electrostatic chuck 1111. At this time, the application of voltage to the first electrode 200 by the first voltage pulse generator 204 is stopped. As a result, the voltage of the first electrode 200 becomes 0 V. In addition, the second voltage pulse generator 214 applies a second reference voltage BV2 to the second electrode 210. As a result, the voltage of the second electrode 210 becomes the second chuck voltage level (vc2) of the second reference voltage BV2. During the first period T1, gas is supplied from the shower head 13 into the chamber 10, and the pressure in the chamber 10 stabilizes.

[0099] During the second period T2, a source RF signal is supplied to the upper electrode and / or the lower electrode, temporarily generating a plasma in the chamber 10. During the second period T2, the first voltage pulse generator 204 applies a first reference voltage BV1 to the first electrode 200. This causes the voltage of the first electrode 200 to be at a first chucking voltage level (vc1) of the first reference voltage BV1. The voltage of the second electrode 210 is maintained at a second chucking voltage level (vc2) of the second reference voltage BV2. During the second period T2, charge is supplied from the plasma to the substrate support surface, the substrate, the link support surface, and the edge ring 250.

[0100] In the third period T3, the supply of the source RF signal to the upper electrode and / or the lower electrode is stopped, and the plasma is extinguished in the chamber 10. For example, a heat transfer gas is supplied to the gap between the back surface of the substrate W and the central region 111 a to adjust the temperature of the substrate on the substrate support surface.

[0101] In the fourth period T4, a plasma process is performed by supplying a source RF signal to the upper electrode and / or the lower electrode, as in the plasma process method described above.

[0102] A first voltage pulse signal PS1 is supplied from a first voltage pulse generator 204 to the first electrode 200, and a first reference voltage BV1 and a first pulse voltage PV1 are alternately applied to the first electrode 200. The first reference voltage BV1 has a first chucking voltage level (vc1). The first pulse voltage PV1 has a first pulse voltage level (v5) and a reference voltage level (v ｒｅｆ１ ) is a sequence of voltage pulses having a first chucking voltage level (vc1) and a reference voltage level (v ｒｅｆ１ ) is a voltage level required to attract and hold the substrate on the substrate support surface. The first pulse voltage level (v5) is a voltage level required to attract and hold the substrate on the substrate support surface and also to attract ion components in the plasma formed above the substrate on the substrate support surface to the substrate W. Therefore, in plasma processing, a bias DC signal is supplied to the electrostatic chuck 1111 while the substrate W is attracted to the electrostatic chuck 1111.

[0103] A second voltage pulse generator 214 supplies a second voltage pulse signal PS2 to the second electrode 210, and a second reference voltage BV2 and a second pulse voltage PV2 are alternately applied to the second electrode 210. The second reference voltage BV2 has a second chucking voltage level (vc2). The second pulse voltage PV2 has a second pulse voltage level (v6) and a reference voltage level (v ｒｅｆ２ ) and a reference voltage level (v ｒｅｆ２ ) is a voltage level required to attract and hold the edge ring 250 on the ring support surface. The second pulse voltage level (v6) is a voltage level required to attract and hold the edge ring 250 on the ring support surface and to attract ion components in the plasma to the outer periphery (edge ​​ring 250) of the substrate W. Therefore, in plasma processing, a bias DC signal is supplied to the outer periphery of the electrostatic chuck 1111 while the edge ring 250 is attracted to the electrostatic chuck 1111.

[0104] During the fifth period T5, the supply of the source RF signal to the upper electrode and / or the lower electrode is stopped. The supply of the heat transfer gas to the gap between the back surface of the substrate W and the central region 111a is also stopped. At this time, the first voltage pulse generator 204 applies a first reference voltage BV1 to the first electrode 200. This causes the voltage of the first electrode 200 to be at a first chucking voltage level (vc1) of the first reference voltage BV1. The second voltage pulse generator 214 applies a second reference voltage BV2 to the second electrode 210. This causes the voltage of the second electrode 210 to be at a second chucking voltage level (vc2) of the second reference voltage BV2.

[0105] During the sixth period T6, a source RF signal is supplied to the upper electrode and / or the lower electrode, temporarily generating plasma in the chamber 10. In the middle of the sixth period T6, the first voltage pulse generator 204 stops applying voltage to the first electrode 200. As a result, the voltage of the first electrode 200 becomes 0 V. Furthermore, the voltage of the second electrode 210 is maintained at the second chuck voltage level (vc2) of the second reference voltage BV2.

[0106] In a seventh period T7, the lifter is raised and lowered, and the substrate is transported from the substrate support surface to the outside of the chamber 10. Thereafter, the first voltage pulse generator 204 temporarily applies a positive voltage to the first electrode 200, thereby de-energizing the electrostatic chuck 1111. At this time, the voltage of the second electrode 210 is maintained at the second chucking voltage level (vc2) of the second reference voltage BV2.

[0107] According to this exemplary embodiment, the plasma processing apparatus 1 includes a first electrode 200 disposed below a substrate support surface within an electrostatic chuck 1111, and a first voltage pulse generator 204 electrically connected to the first electrode 200 and configured to generate a first voltage pulse signal PS1. The first voltage pulse signal PS1 includes a first reference voltage BV1 and a first pulse voltage PV1 that are alternately repeated, the first reference voltage BV1 having a first chuck voltage level (vc1), and the first pulse voltage PV1 having a first pulse voltage level (v5), the absolute value of which is greater than the absolute value of the first chuck voltage level (vc1). According to this embodiment, the single first electrode 200 is used to increase the capacitance from the electrode to the substrate, and by applying an appropriate voltage to the first electrode 200, it is possible to suppress attenuation of the surface potential of the substrate during plasma processing.

[0108] According to this exemplary embodiment, the plasma processing apparatus 1 further includes an edge ring 250, a second electrode 210 disposed below the ring support surface within the electrostatic chuck 1111, and a second voltage pulse generator 214 electrically connected to the second electrode 210 and configured to generate a second voltage pulse signal PS2. The second voltage pulse signal PS2 includes a second reference voltage BV2 and a second pulse voltage PV2 that alternately repeat, where the second reference voltage BV2 has a second chuck voltage level (vc2), and the second pulse voltage PV2 has a second pulse voltage level (v6), the absolute value of which is greater than the absolute value of the second chuck voltage level (vc2). According to this embodiment, the single second electrode 210 is used to increase the capacitance from the electrode to the edge ring, and by applying an appropriate voltage to the second electrode 210, it is possible to suppress attenuation of the surface potential of the edge ring during plasma processing. Furthermore, the difference between the surface potential of the substrate and the surface potential of the edge ring during plasma processing can be reduced.

[0109] <Modification> In the second embodiment, the first power supply 203 may include multiple power supplies. Each of the multiple power supplies may be configured to generate a different first DC voltage DCV1(n) (n is an integer). The second power supply 213 may include multiple power supplies. Each of the multiple power supplies may be configured to generate a different second DC voltage DCV2(n) (n is an integer). For example, as shown in FIG. 14 , the first power supply 203 may include two power supplies 203a and 203b, where the power supply 203a generates the first DC voltage DCV1(1) and the power supply 203b generates the first DC voltage DCV1(2). The first DC voltage DCV1(1) of the power supply 203a may have a first chuck voltage level (vc1), and the first DC voltage DCV1(2) of the power supply 203b may have a first pulse voltage level (v5). Each of the power supplies 203 a, 203 b is electrically connected to a first voltage pulse generator 204. The first voltage pulse generator 204 may generate a first voltage pulse signal PS1 from a plurality of first DC voltage DCV1(n) signals supplied from the plurality of power supplies 203 a, 203 b.

[0110] In the second embodiment, the second power supply 213 may include two power supplies 213a and 213b. The power supply 213a may generate a second DC voltage DCV2(1), and the power supply 213b may generate a second DC voltage DCV2(2). The second DC voltage DCV2(1) of the power supply 213a may have a second chuck voltage level (vc2), and the second DC voltage DCV2(2) of the power supply 213b may have a second pulse voltage level (v6). Each of the power supplies 213a and 213b may be electrically connected to a second voltage pulse generator 214. The second voltage pulse generator 214 may generate a second voltage pulse signal PS2 from the signals of the plurality of second DC voltages DCV2(n) supplied from the plurality of power supplies 213a and 213b. In addition, the second voltage pulse generator 214 may generate a second voltage pulse signal PS2 from a plurality of second DC voltage DCV2(n) signals supplied from a plurality of power sources 213a, 213b and a plurality of first DC voltage DCV1(n) signals supplied from a plurality of power sources 203a, 203b.

[0111] In the second embodiment, the plurality of first voltage pulses P1(n) are not limited to the example illustrated in FIG. 11 . The plurality of first voltage pulses P1(n) may be any voltage pulse that can attract the substrate W to the electrostatic chuck 1111 and supply bias energy to the substrate W. For example, as shown in FIG. 15 , the plurality of first voltage pulses P1(n) may be a sequence of voltage pulses that alternately include a first negative voltage level (V51) and a second negative voltage level (V52). The absolute value of the first negative voltage level (V51) is greater than the absolute value of the second negative voltage level (V52). In one embodiment, the second negative voltage level (v52) may be different from the first chucking voltage level (vc1) as long as the second negative voltage level (v52) is large enough to attract and hold the substrate on the substrate support surface. For example, the absolute value of the second negative voltage level (v52) may be smaller than the absolute value of the first chucking voltage level (vc1). In one embodiment, the first negative voltage level (v51) may be in the range of −3000 V to −15000 V, or may be in the range of −4000 V to −10000 V. In one embodiment, the second negative voltage level (v51) may be in the range of −500 V to −6000 V, or may be in the range of −500 V to −2000 V. In one embodiment, the first chucking voltage level (vc1) may be in the range of −1000 V to −10000 V, or may be in the range of −2000 V to −4000 V.

[0112] In the second embodiment, the plurality of second voltage pulses P2(n) are not limited to the example illustrated in FIG. 12 . The plurality of second voltage pulses P2(n) may be any pulses capable of supplying bias energy to the edge ring 250 while attracting and holding the edge ring 250 to the ring support surface. For example, as shown in FIG. 16 , the plurality of second voltage pulses P2(n) may be a sequence of voltage pulses that alternately include a third negative voltage level (V61) and a fourth negative voltage level (V62). The absolute value of the third negative voltage level (V61) is greater than the absolute value of the fourth negative voltage level (V62). In one embodiment, the fourth negative voltage level (v62) may be different from the second chucking voltage level (vc2) as long as the fourth negative voltage level (v62) is large enough to attract and hold the edge ring 250 to the ring support surface. For example, the absolute value of the fourth negative voltage level (v62) may be smaller than the absolute value of the second chucking voltage level (vc2). In one embodiment, the third negative voltage level (v61) may be in the range of −3000 V to −15000 V, or may be in the range of −4000 V to −10000 V. In one embodiment, the fourth negative voltage level (v62) may be in the range of −500 V to −6000 V, or may be in the range of −500 V to −2000 V. In one embodiment, the second chucking voltage level (vc1) may be in the range of −1000 V to −10000 V, or may be in the range of −2000 V to −4000 V.

[0113] In an embodiment of the present disclosure, the first electrode 200 and / or the second electrode 210 may be configured as a plurality of electrodes divided in the radial and / or circumferential directions. Each of the plurality of first electrodes 200 may be a monopolar electrode that applies a voltage between itself and the substrate, or may be a bipolar electrode that establishes a potential difference between itself. Similarly, each of the plurality of second electrodes 200 may be a monopolar electrode that applies a voltage between itself and the substrate, or may be a bipolar electrode that establishes a potential difference between itself.

[0114] For example, as shown in FIG. 17 , the plasma processing apparatus 1 may include bipolar electrodes 200a and 200b as the first electrode 200. The bipolar electrodes 200a and 200b are disposed below the substrate support surface (central region 111a) in the electrostatic chuck 1111. The bipolar electrodes 200a and 200b may be disposed on the same plane. The bipolar electrodes 200a and 200b may have various shapes, such as a semicircular shape, a comb-like shape, or a mesh-like shape, in a planar view. The bipolar electrode 200a may be electrically connected to a voltage pulse generator 204a via a low-pass filter 270a, a switch 271a, etc. The bipolar electrode 200b may be electrically connected to a voltage pulse generator 204b via a low-pass filter 270b, a switch 271b, etc. The voltage pulse generators 204 a and 204 b may be integrally configured as part of the first voltage pulse generator 204 .

[0115] In one embodiment, the bipolar electrodes 200a and 200b serve as both substrate chucking electrodes and substrate bias electrodes. In one embodiment, the bipolar electrodes 200a and 200b may function as substrate chucking electrodes during substrate chucking. For example, during substrate chucking, the voltage pulse generator 204a may be configured to apply a reference voltage BV1a to the bipolar electrode 200a. The voltage pulse generator 204b may be configured to apply a reference voltage BV1b to the bipolar electrode 200b during substrate chucking. This creates an electric polarization in the substrate, attracting the substrate to the bipolar electrodes 200a and 200b and holding it against the substrate support surface.

[0116] In one embodiment, reference voltages BV1a and BV1b may have opposite polarities. For example, voltage pulse generator 204a may apply reference voltage BV1a having a negative chucking voltage level (-vc) to bipolar electrode 200a. Voltage pulse generator 204b may apply reference voltage BV1b having a positive chucking voltage level (+vc) to bipolar electrode 200b. In one embodiment, the absolute value of the chucking voltage level is in the range of 1000V to 10000V.

[0117] In one embodiment, the bipolar electrodes 200a and 200b can function as both a substrate bias electrode and a substrate chuck electrode during plasma processing. For example, during plasma processing of a substrate, the voltage pulse generator 204a can be configured to apply a pulsed voltage PV1a to the bipolar electrode 200a. The voltage pulse generator 204b can be configured to apply a pulsed voltage PV1b to the bipolar electrode 200b during plasma processing of the substrate. As shown in FIG. 18 , in one embodiment, the pulsed voltage PV1a includes a plurality of voltage pulses P1a(n) (n is an integer), and the pulsed voltage PV1b includes a plurality of voltage pulses P1b(n) (n is an integer).

[0118] In one embodiment, each voltage pulse of the plurality of voltage pulses P1a(n) has a first negative voltage level (V71) and a zero voltage level during the alternating first period p1 and second period p2, respectively. In one embodiment, the pulse voltage PV1a may have a third negative voltage level (V73) before the repetition of the first period p1 and the second period p2. The absolute value of the third negative voltage level (V73) is smaller than that of the first negative voltage level (V71). In one embodiment, each of the plurality of voltage pulses P1a(n) may have a rectangular pulse waveform, or may have various pulse waveforms other than rectangular, such as trapezoidal, triangular, or a combination thereof.

[0119] In one embodiment, each voltage pulse of the plurality of voltage pulses P1b(n) has a zero voltage level and a second negative voltage level (V72) during the alternating first period p1 and second period p2, respectively. In one embodiment, the pulse voltage PV1b may have the zero voltage level before the repetition of the first period p1 and the second period p2. In one embodiment, each of the plurality of voltage pulses P1b(n) may have a rectangular pulse waveform, or may have various pulse waveforms other than rectangular, such as trapezoidal, triangular, or a combination thereof.

[0120] During a first period p1 during plasma processing, a pulse voltage PV1a of a first negative voltage level (V71) is applied to the bipolar electrode 200a. During a second period p2 during plasma processing, a pulse voltage PV1b of a second negative voltage level (V72) is applied to the bipolar electrode 200b. This draws ion components in the plasma into the substrate. That is, the bipolar electrodes 200a and 200b can function as substrate bias electrodes during plasma processing.

[0121] Furthermore, during both the first period p1 and the second period p2 during plasma processing, the potential difference between the plurality of voltage pulses P1a(n) and the plurality of voltage pulses P1b(n) does not become zero (in the example shown in FIG. 18 , there is a potential difference of the first negative voltage level V71 or the second negative voltage level V72 during both the first period p1 and the second period p2). This generates a potential difference between the bipolar electrodes 200a and 200b, which generates dielectric polarization in the substrate, resulting in the substrate being attracted to the electrostatic chuck 1111. In other words, the bipolar electrodes 200a and 200b can also function as substrate chucking electrodes during plasma processing.

[0122] The first negative voltage level (V71) and the second negative voltage level (V72) may be voltage levels required to attract and hold the substrate on the substrate support surface by dielectric polarization and to attract ion components in plasma formed above the substrate on the substrate support surface to the substrate. In one embodiment, the first negative voltage level (V71) is within the range of −3000 V to −15000 V. In one embodiment, the second negative voltage level (V72) is within the range of −3000 V to −15000 V. In one embodiment, the first negative voltage level (V71) is equal to the second negative voltage level (V71). In one embodiment, the third negative voltage level (V73) is within the range of −3000 V to −15000 V.

[0123] Embodiments of the present disclosure further include the following aspects.

[0124] a first switch; a first chuck power supply electrically connected to the first electrode via the first switch; a first voltage pulse generator electrically connected to the first electrode; and a controller configured to control the first switch, the first chuck power supply, and the first voltage pulse generator to alternately apply a first reference voltage and a first pulse voltage to the first electrode during plasma processing of a substrate on the substrate support surface, the first reference voltage having a first chuck voltage level, the first pulse voltage having a first pulse voltage level, and an absolute value of the first pulse voltage level being greater than an absolute value of the first chuck voltage level.

[0125] (Supplementary Note 2) The plasma processing apparatus of Supplementary Note 1, wherein the first chucking voltage level and the first pulse voltage level have negative polarity.

[0126] (Supplementary Note 3) The plasma processing apparatus according to Supplementary Note 1 or 2, wherein the first chuck power supply is configured to generate a voltage having the first chuck voltage level, and the first voltage pulse generator is configured to generate a voltage having a voltage level corresponding to a difference between the first chuck voltage level and the first pulse voltage level.

[0127] (Supplementary Note 4) The plasma processing apparatus according to any one of Supplementary Notes 1 to 3, wherein the first chuck voltage level is in a range of −1000V to −10000V, and the first pulse voltage level is in a range of −10000V to −20000V.

[0128] (Supplementary Note 5) The electrostatic chuck further has a ring support surface, and the substrate support unit further has: at least one edge ring disposed on the ring support surface to surround a substrate on the substrate support surface; and a second electrode disposed within the electrostatic chuck below the ring support surface, and the plasma processing apparatus further includes: a second switch; a second chuck power supply electrically connected to the second electrode via the second switch; and a second voltage pulse generator electrically connected to the second electrode, and the controller is configured to control the second switch, the second chuck power supply, and the second voltage pulse generator to alternately apply a second reference voltage and a second pulse voltage to the second electrode during plasma processing of the substrate on the substrate support surface, the second reference voltage having a second chuck voltage level, and the second pulse voltage having a second pulse voltage level, and an absolute value of the second pulse voltage level being greater than the absolute value of the second chuck voltage level. 5. The plasma processing apparatus according to claim 1.

[0129] (Supplementary Note 6) The plasma processing apparatus according to Supplementary Note 5, wherein the second chucking voltage level and the second pulse voltage level have negative polarity.

[0130] (Supplementary Note 7) The plasma processing apparatus according to Supplementary Note 5 or 6, wherein the second chuck power supply is configured to generate a voltage having the second chuck voltage level, and the second voltage pulse generator is configured to generate a voltage having a voltage level corresponding to a difference between the second chuck voltage level and the second pulse voltage level.

[0131] (Supplementary Note 8) The plasma processing apparatus according to any one of Supplementary Notes 5 to 7, wherein the second chucking voltage level is equal to the first chucking voltage level.

[0132] (Supplementary Note 9) The plasma processing apparatus according to any one of Supplementary Notes 5 to 8, wherein an absolute value of the second pulse voltage level is greater than an absolute value of the first pulse voltage level.

[0133] (Supplementary Note 10) The plasma processing apparatus according to any one of Supplementary Notes 5 to 9, wherein the second chuck voltage level is in a range of −1000V to −10000V, and the second pulse voltage level is in a range of −10000V to −20000V.

[0134] (Supplementary Note 11) A plasma processing apparatus comprising: a plasma processing chamber; and a substrate support disposed within the plasma processing chamber, the substrate support including: a base; an electrostatic chuck disposed on the base and having a substrate support surface; and a first electrode disposed within the electrostatic chuck below the substrate support surface; and a first voltage pulse generator electrically connected to the first electrode and configured to generate a first voltage pulse signal, the first voltage pulse signal including an alternating first reference voltage and a first pulse voltage, the first reference voltage having a first chuck voltage level, the first pulse voltage having a first pulse voltage level, and an absolute value of the first pulse voltage level being greater than an absolute value of the first chuck voltage level.

[0135] (Supplementary Note 12) The plasma processing apparatus of Supplementary Note 11, wherein the first chucking voltage level and the first pulse voltage level have negative polarity.

[0136] (Supplementary Note 13) The plasma processing apparatus according to Supplementary Note 11 or 12, wherein the first chuck voltage level is in a range of −1000V to −10000V, and the first pulse voltage level is in a range of −10000V to −20000V.

[0137] (Supplementary Note 14) The plasma processing apparatus of any one of Supplementary Notes 11 to 13, wherein the electrostatic chuck further has a ring support surface, and the substrate support further has: at least one edge ring disposed on the ring support surface to surround the substrate on the substrate support surface; and a second electrode disposed within the electrostatic chuck below the ring support surface, and the plasma processing apparatus further includes: a second voltage pulse generator electrically connected to the second electrode and configured to generate a second voltage pulse signal, the second voltage pulse signal having an alternating second reference voltage and a second pulse voltage, the second reference voltage having a second chuck voltage level, the second pulse voltage having a second pulse voltage level, and an absolute value of the second pulse voltage level being greater than the absolute value of the second chuck voltage level.

[0138] (Supplementary Note 15) The plasma processing apparatus of Supplementary Note 14, wherein the second chucking voltage level and the second pulse voltage level have negative polarity.

[0139] (Supplementary Note 16) The plasma processing apparatus according to Supplementary Note 14 or 15, wherein the second chucking voltage level is equal to the first chucking voltage level.

[0140] (Supplementary Note 17) The plasma processing apparatus according to any one of Supplementary Notes 14 to 16, wherein an absolute value of the second pulse voltage level is greater than an absolute value of the first pulse voltage level.

[0141] (Supplementary Note 18) The plasma processing apparatus according to any one of Supplementary Notes 14 to 17, wherein the second chuck voltage level is in a range of −1000V to −10000V, and the second pulse voltage level is in a range of −10000V to −20000V.

[0142] (Supplementary Note 19) A plasma processing apparatus comprising: a plasma processing chamber; and a substrate support disposed within the plasma processing chamber, the substrate support including: a base; an electrostatic chuck disposed on the base and having a substrate support surface; and a first electrode disposed within the electrostatic chuck below the substrate support surface; and a first voltage pulse generator electrically connected to the first electrode and configured to generate a first pulse voltage, the first pulse voltage having alternating first and second negative voltage levels to supply bias energy to the substrate on the substrate support surface while maintaining a chucked state of the substrate to the substrate support surface, the absolute value of the first negative voltage level being greater than the absolute value of the second negative voltage level.

[0143] (Supplementary Note 20) The plasma processing apparatus according to Supplementary Note 19, wherein the first pulse voltage has a third negative voltage level before the repetition of the first negative voltage level and the second negative voltage level, and the absolute value of the third negative voltage level is smaller than the absolute value of the first negative voltage level and larger than the absolute value of the second negative voltage level.

[0144] (Supplementary Note 21) The plasma processing apparatus according to Supplementary Note 19 or 20, wherein the first negative voltage level is within a range of −3000V to −15000V.

[0145] (Supplementary Note 22) The plasma processing apparatus according to any one of Supplementary Notes 19 to 21, wherein the second negative voltage level is within a range of −500V to −6000V.

[0146] (Supplementary Note 23) The plasma processing apparatus according to Supplementary Note 20, wherein the third negative voltage level is within a range of −1000V to −10000V.

[0147] (Supplementary Note 24) The plasma processing apparatus according to any one of Supplementary Notes 19 to 24, wherein a distance between the substrate support surface and the first electrode is 0.3 mm or less.

[0148] (Supplementary Note 25) A plasma processing apparatus comprising: a plasma processing chamber; and a substrate support disposed within the plasma processing chamber, the substrate support including: a base; an electrostatic chuck disposed on the base and having a substrate support surface; and a first electrode and a second electrode disposed within the electrostatic chuck below the substrate support surface; a first voltage pulse generator electrically connected to the first electrode and configured to generate a first pulse voltage; and a second voltage pulse generator electrically connected to the second electrode and configured to generate a second pulse voltage, wherein the first pulse voltage has a first negative voltage level and a zero voltage level in alternatingly repeated first and second periods, respectively; and the second pulse voltage has a zero voltage level and a second negative voltage level in the first and second periods, respectively.

[0149] (Supplementary Note 26) The plasma processing apparatus according to Supplementary Note 25, wherein the first pulse voltage has a third negative voltage level before the repetition of the first period and the second period, and the absolute value of the third negative voltage level is smaller than the absolute values ​​of the first negative voltage level and the second negative voltage level.

[0150] (Supplementary Note 27) The plasma processing apparatus according to Supplementary Note 25 or 26, wherein the first voltage pulse generator and the second voltage pulse generator are integrated.

[0151] (Supplementary Note 28) The plasma processing apparatus according to any one of Supplementary Notes 25 to 27, wherein the first negative voltage level and the second negative voltage level are within a range of −3000V to −15000V.

[0152] (Supplementary Note 29) The plasma processing apparatus according to any one of Supplementary Notes 25 to 28, wherein the first negative voltage level is equal to the second negative voltage level.

[0153] (Supplementary Note 30) The plasma processing apparatus according to Supplementary Note 26, wherein the third negative voltage level is within a range of −1000V to −10000V.

[0154] (Supplementary Note 31) The plasma processing apparatus according to any one of Supplementary Notes 25 to 30, wherein a distance between the substrate support surface and the first electrode is 0.3 mm or less.

[0155] The above embodiments are described for the purpose of explanation and are not intended to limit the scope of the present disclosure. Various modifications can be made to the above embodiments without departing from the scope and spirit of the present disclosure. For example, some components in one embodiment can be added to other embodiments. Also, some components in one embodiment can be replaced with corresponding components in other embodiments.

[0156] REFERENCE SIGNS LIST 1... plasma processing apparatus, 2... control unit, 10... chamber, 11... substrate support unit, 1111... electrostatic chuck, 200... first electrode, 201... first switch, 202... first chuck power supply, 203... first power supply, 204... first voltage pulse generator, 210... second electrode, 211... second switch, 212... second chuck power supply, 213... second power supply, 214... second voltage pulse generator, 250... edge ring, W... substrate

Claims

1. A plasma processing apparatus comprising: a plasma processing chamber; and a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode disposed within the electrostatic chuck below the substrate support surface; a first switch; a first chuck power supply electrically connected to the first electrode via the first switch; a first voltage pulse generator electrically connected to the first electrode; and a controller, wherein the controller is configured to control the first switch, the first chuck power supply, and the first voltage pulse generator to alternately apply a first reference voltage and a first pulse voltage to the first electrode during plasma processing of a substrate on the substrate support surface, wherein the first reference voltage has a first chuck voltage level, and the first pulse voltage has a first pulse voltage level, and the absolute value of the first pulse voltage level is greater than the absolute value of the first chuck voltage level.

2. The plasma processing apparatus of claim 1, wherein the first chucking voltage level and the first pulse voltage level have negative polarity.

3. The plasma processing apparatus of claim 2, wherein the first chuck power supply is configured to generate a voltage having the first chuck voltage level, and the first voltage pulse generator is configured to generate a voltage having a voltage level corresponding to a difference between the first chuck voltage level and the first pulse voltage level.

4. The plasma processing apparatus of claim 1, wherein the first chuck voltage level is in the range of -1000V to -10000V, and the first pulse voltage level is in the range of -10000V to -20000V.

5. The electrostatic chuck further has a ring support surface, and the substrate support unit further has: at least one edge ring disposed on the ring support surface to surround a substrate on the substrate support surface; and a second electrode disposed within the electrostatic chuck below the ring support surface, and the plasma processing apparatus further includes: a second switch; a second chuck power supply electrically connected to the second electrode via the second switch; and a second voltage pulse generator electrically connected to the second electrode, and the controller is configured to control the second switch, the second chuck power supply, and the second voltage pulse generator to alternately apply a second reference voltage and a second pulse voltage to the second electrode during plasma processing of the substrate on the substrate support surface, the second reference voltage having a second chuck voltage level, and the second pulse voltage having a second pulse voltage level, and the absolute value of the second pulse voltage level being greater than the absolute value of the second chuck voltage level. The plasma processing apparatus according to claim 1 .

6. The plasma processing apparatus of claim 5, wherein the second chucking voltage level and the second pulse voltage level have negative polarity.

7. The plasma processing apparatus of claim 6, wherein the second chuck power supply is configured to generate a voltage having the second chuck voltage level, and the second voltage pulse generator is configured to generate a voltage having a voltage level corresponding to a difference between the second chuck voltage level and the second pulse voltage level.

8. The plasma processing apparatus of claim 6, wherein the second chucking voltage level is equal to the first chucking voltage level.

9. The plasma processing apparatus according to claim 6, wherein the absolute value of the second pulse voltage level is greater than the absolute value of the first pulse voltage level.

10. The plasma processing apparatus of claim 5, wherein the second chuck voltage level is in the range of -1000V to -10000V, and the second pulse voltage level is in the range of -10000V to -20000V.

11. A plasma processing apparatus comprising: a plasma processing chamber; and a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode disposed within the electrostatic chuck below the substrate support surface; and a first voltage pulse generator electrically connected to the first electrode and configured to generate a first voltage pulse signal, the first voltage pulse signal having an alternating first reference voltage and a first pulse voltage, the first reference voltage having a first chuck voltage level, and the first pulse voltage having a first pulse voltage level, the absolute value of the first pulse voltage level being greater than the absolute value of the first chuck voltage level.

12. The plasma processing apparatus of claim 11, wherein the first chucking voltage level and the first pulsed voltage level have negative polarity.

13. The plasma processing apparatus of claim 11, wherein the first chucking voltage level is in the range of -1000V to -10000V, and the first pulsed voltage level is in the range of -10000V to -20000V.

14. The plasma processing apparatus of any one of claims 11 to 13, wherein the electrostatic chuck further comprises a ring support surface, and the substrate support further comprises: at least one edge ring disposed on the ring support surface to surround a substrate on the substrate support surface; and a second electrode disposed within the electrostatic chuck below the ring support surface, and the plasma processing apparatus further comprises: a second voltage pulse generator electrically connected to the second electrode and configured to generate a second voltage pulse signal, the second voltage pulse signal having an alternating second reference voltage and a second pulse voltage, the second reference voltage having a second chuck voltage level, the second pulse voltage having a second pulse voltage level, and an absolute value of the second pulse voltage level being greater than the absolute value of the second chuck voltage level.

15. The plasma processing apparatus of claim 14, wherein the second chucking voltage level and the second pulsed voltage level have negative polarity.

16. The plasma processing apparatus of claim 15, wherein the second chucking voltage level is equal to the first chucking voltage level.

17. The plasma processing apparatus according to claim 15, wherein the absolute value of the second pulse voltage level is greater than the absolute value of the first pulse voltage level.

18. The plasma processing apparatus of claim 14, wherein the second chucking voltage level is in the range of -1000V to -10000V, and the second pulsed voltage level is in the range of -10000V to -20000V.

19. A plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode disposed within the electrostatic chuck below the substrate support surface; and a first voltage pulse generator electrically connected to the first electrode and configured to generate a first pulse voltage having alternating first and second negative voltage levels to supply bias energy to the substrate on the substrate support surface while maintaining a chucked state of the substrate to the substrate support surface, the absolute value of the first negative voltage level being greater than the absolute value of the second negative voltage level.

20. The plasma processing apparatus of claim 19, wherein the first pulse voltage has a third negative voltage level before the repetition of the first negative voltage level and the second negative voltage level, and the absolute value of the third negative voltage level is smaller than the absolute value of the first negative voltage level and greater than the absolute value of the second negative voltage level.

21. The plasma processing apparatus according to claim 19 or 20, wherein the first negative voltage level is in the range of −3000V to −15000V.

22. The plasma processing apparatus of claim 21, wherein the second negative voltage level is in the range of -500V to -6000V.

23. The plasma processing apparatus of claim 20, wherein the third negative voltage level is in the range of -1000V to -10000V.

24. The plasma processing apparatus according to claim 19 or 20, wherein the distance between the substrate support surface and the first electrode is 0.3 mm or less.

25. A plasma processing apparatus comprising: a plasma processing chamber; and a substrate support disposed within the plasma processing chamber, the substrate support including a base, an electrostatic chuck disposed on the base and having a substrate support surface, and a first electrode and a second electrode disposed within the electrostatic chuck below the substrate support surface; a first voltage pulse generator electrically connected to the first electrode and configured to generate a first pulsed voltage; and a second voltage pulse generator electrically connected to the second electrode and configured to generate a second pulsed voltage, wherein the first pulsed voltage has a first negative voltage level and a zero voltage level in alternating first and second periods, respectively, and the second pulsed voltage has a zero voltage level and a second negative voltage level in the first and second periods, respectively.

26. The plasma processing apparatus of claim 25, wherein the first pulse voltage has a third negative voltage level before the repetition of the first period and the second period, and the absolute value of the third negative voltage level is smaller than the absolute values ​​of the first negative voltage level and the second negative voltage level.

27. The plasma processing apparatus of claim 26, wherein the first voltage pulse generator and the second voltage pulse generator are integrated.

28. The plasma processing apparatus according to any one of claims 25 to 27, wherein the first negative voltage level and the second negative voltage level are within a range of -3000V to -15000V.

29. The plasma processing apparatus of claim 28, wherein the first negative voltage level is equal to the second negative voltage level.

30. The plasma processing apparatus of claim 26, wherein the third negative voltage level is in the range of -1000V to -10000V.

31. The plasma processing apparatus according to any one of claims 25 to 27, wherein the distance between the substrate support surface and the first electrode is 0.3 mm or less.

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