Plasma processing apparatus and substrate processing system

Abstract

The disclosed plasma processing apparatus includes a chamber, a substrate support, an edge ring, a lift mechanism, a plasma generating unit, and a bias power supply. The substrate support is disposed in the chamber. The lift mechanism is configured to move the edge ring up and down relative to the substrate support. The substrate support includes a base electrically coupled to the bias power supply and / or the high frequency power supply of the plasma generating unit, and an electrostatic chuck on the base. The lift mechanism includes a conductive ring and a connecting member, the conductive ring supporting the edge ring placed thereon and electrically connecting to the edge ring. The connecting member is configured to maintain an electrical connection between the conductive ring and the base in response to the movement of the edge ring and the conductive ring by the lift mechanism.

Description

[Technical field]

[0001] Exemplary embodiments of the present disclosure relate to a plasma processing apparatus and a substrate processing system. [Background technology]

[0002] A plasma processing apparatus is used for plasma processing of a substrate. The plasma processing apparatus includes a chamber and a substrate support. The substrate support is disposed in the chamber. The substrate support includes a base and an electrostatic chuck. A bias power supply is connected to the base, which generates an electric bias for attracting ions from the plasma to the substrate. The electrostatic chuck is configured to support the substrate and an edge ring surrounding the substrate. Patent Document 1 listed below discloses a plasma processing apparatus configured to move the edge ring up and down. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-113753 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides techniques for reducing the difference between the location of the top of the plasma sheath above the edge ring and the location of the top of the plasma sheath above the substrate. [Means for solving the problem]

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, an edge ring, a lift mechanism, a plasma generating unit, and a bias power supply. The substrate support is disposed in the chamber. The edge ring is electrically conductive and disposed to surround a substrate on the substrate support. The lift mechanism is configured to move the edge ring up and down. The plasma generating unit includes a high frequency power supply and is configured to generate a plasma in the chamber. The bias power supply is configured to generate an electrical bias to attract ions from the plasma to the substrate on the substrate support. The substrate support includes a base electrically coupled to the bias power supply and / or the high frequency power supply, and an electrostatic chuck on the base. The lift mechanism includes a conductive ring, a rod, an actuator, and a connecting member. The conductive ring supports the edge ring placed thereon and is electrically connected to the edge ring. The rod extends vertically below the conductive ring. The actuator is configured to move the edge ring up and down via the rod and the conductive ring. The connecting member provides an electrical connection between the conductive ring and the base. The connection member is configured to maintain the electrical connection in response to movement of the conductive ring. Effect of the Invention

[0006] According to one exemplary embodiment, it is possible to reduce the difference between the location of the top of the plasma sheath on the edge ring and the location of the top of the plasma sheath on the substrate. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram for explaining a configuration example of a plasma processing system. [Diagram 2] FIG. 1 is a diagram for explaining a configuration example of an inductively coupled plasma processing apparatus. [Diagram 3] FIG. 2 illustrates a substrate support and lift mechanism according to an example embodiment. [Figure 4] FIG. 1 illustrates a substrate support and lift mechanism of another exemplary embodiment. [Diagram 5] FIG. 1 illustrates a substrate processing system according to an exemplary embodiment. [Figure 6] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 7] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 8] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 9] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 10] FIG. 1 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. [Figure 11] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 12] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 13] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 14] 1 is a flow diagram illustrating a plasma processing method according to an exemplary embodiment. [Figure 15] FIG. 15(a) is a diagram illustrating an example of an imaging device that can be used with the plasma processing apparatus according to various exemplary embodiments, and FIG. 15(b) is a diagram illustrating an example of a measuring device that can be used with the plasma processing apparatus according to various exemplary embodiments. [Figure 16] 4 is a flow diagram illustrating a plasma processing method according to another exemplary embodiment. [Figure 17] 13 is a flow diagram illustrating a plasma processing method according to yet another exemplary embodiment. [Figure 18] 1A-1C illustrate example metrology instruments for use with plasma processing apparatus according to various exemplary embodiments. [Figure 19] FIG. 13 illustrates an edge ring and a conductive ring according to yet another exemplary embodiment. [Figure 20]FIG. 13 illustrates an edge ring and a conductive ring according to yet another exemplary embodiment. [Figure 21] FIG. 13 illustrates a substrate support and lift mechanism according to yet another exemplary embodiment. [Figure 22] 13 is a graph showing experimental results. [Diagram 23] FIG. 2 illustrates a substrate support and lift mechanism according to an example embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Various exemplary embodiments will now be described in detail with reference to the drawings, in which the same or corresponding parts are designated by the same reference numerals.

[0009] FIG. 1 is a diagram for explaining a configuration example of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing device 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing device 1 is an example of a substrate processing device. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support unit 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 unit 11 is disposed in the plasma processing space, and has a substrate support surface for supporting a substrate.

[0010] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR plasma), a helicon wave plasma (HWP), a surface wave plasma (SWP), or the like. Also, various types of plasma generating units may be used, including an alternating current (AC) plasma generating unit and a direct current (DC) plasma generating unit. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Thus, the AC signal includes a radio frequency (RF) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0011] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to execute various steps described in the present disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to execute various steps described herein. In one embodiment, a 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 is realized, for example, by a computer 2a. The processing unit 2a1 may be configured to perform various control operations by reading a program from the storage unit 2a2 and executing the read program. This program may be stored in the storage unit 2a2 in advance, or may be acquired via a medium when necessary. The acquired program is stored in the storage unit 2a2 and is read from the storage unit 2a2 by the processing unit 2a1 and executed. The medium may be various storage media readable by the computer 2a, or may be 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).

[0012] The following describes a configuration example of an inductively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining the configuration example of the inductively coupled plasma processing apparatus.

[0013] The inductively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing chamber 10 includes a dielectric window 101. The plasma processing apparatus 1 also includes a substrate support 11, a gas inlet, and an antenna 14. The substrate support 11 is disposed within the plasma processing chamber 10. The antenna 14 is disposed on or above the plasma processing chamber 10 (i.e., on or above the dielectric window 101). The plasma processing chamber 10 has a plasma processing space 10s defined by the dielectric window 101, a sidewall 102 of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 is grounded.

[0014] 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 the substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of the 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.

[0015] In one embodiment, the 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 may function as a bias 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 other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have the annular region 111b. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF power source 31 and / or a DC power source 32 described below may be disposed in the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple bias electrodes. Also, the electrostatic electrode 1111b may function as a bias electrode. Thus, the substrate support 11 includes at least one bias electrode.

[0016] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0017] 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 a 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 back surface of the substrate W and the central region 111a.

[0018] The gas introduction unit is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. In one embodiment, the gas introduction unit includes a center gas injector (CGI) 13. The center gas injector 13 is disposed above the substrate support 11 and attached to a central opening formed in the dielectric window 101. The center gas injector 13 has at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas inlet port 13c. The processing gas supplied to the gas supply port 13a passes through the gas flow path 13b and is introduced into the plasma processing space 10s from the gas inlet port 13c. Note that the gas introduction unit may include one or more side gas injectors (SGI) attached to one or more openings formed in the sidewall 102 in addition to or instead of the center gas injector 13.

[0019] The gas supply 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply 20 is configured to supply at least one process gas from a respective gas source 21 to the gas inlet via a respective 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 20 may include at least one flow modulation device to modulate or pulse a flow rate of the at least one process gas.

[0020] The power source 30 includes an RF power source 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power source 31 is configured to supply at least one RF signal (RF power) to at least one bias electrode and the antenna 14. This causes a plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power source 31 can function as at least a part of the plasma generating unit 12. In addition, by supplying a bias RF signal to the at least one bias electrode, a bias potential is generated on the substrate W, and ions in the formed plasma can be attracted to the substrate W.

[0021] 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 the antenna 14 via at least one impedance matching circuit and 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 a plurality of source RF signals having different frequencies. The generated one or more source RF signals are supplied to the antenna 14.

[0022] The second RF generating unit 31b is coupled to at least one bias electrode via at least one impedance matching circuit and configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generating unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one bias electrode. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0023] 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 bias DC generator 32a. In one embodiment, the bias DC generator 32a is connected to at least one bias electrode and configured to generate a bias DC signal. The generated bias DC signal is applied to the at least one bias electrode.

[0024] In various embodiments, the bias DC signal may be pulsed. In this case, a sequence of voltage pulses is applied to at least one bias electrode. The voltage pulses may have a rectangular, trapezoidal, triangular or combination of these pulse waveforms. In one embodiment, a waveform generator for generating a sequence of voltage pulses from the DC signal is connected between the bias DC generator 32a and at least one bias electrode. Thus, the bias DC generator 32a and the waveform generator constitute a voltage pulse generator. The voltage pulses may have a positive polarity or a negative polarity. Also, the sequence of voltage pulses may include one or more positive polarity voltage pulses and one or more negative polarity voltage pulses within one period. Note that the bias DC generator 32a may be provided in addition to the RF power supply 31 or may be provided instead of the second RF generator 31b.

[0025] The antenna 14 includes one or more coils. In one embodiment, the antenna 14 may include an outer coil and an inner coil arranged coaxially. In this case, the RF power source 31 may be connected to both the outer coil and the inner coil, or to either the outer coil or the inner coil. In the former case, the same RF generator may be connected to both the outer coil and the inner coil, or separate RF generators may be connected to the outer coil and the inner coil separately.

[0026] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is adjusted by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0027] Reference is now made to Fig. 3, which illustrates a substrate support and lift mechanism according to an exemplary embodiment. The substrate support 11 and lift mechanism 50 illustrated in Fig. 3 may be employed in a plasma processing apparatus 1.

[0028] As described above, the substrate support 11 is configured to support an edge ring UR (upper edge ring). The edge ring UR is a part of the ring assembly 112. The edge ring UR is disposed to surround the substrate W on the substrate support 11. The edge ring UR is made of a conductive material such as silicon, silicon carbide, tungsten, etc.

[0029] The substrate support 11 includes a base 1110 and an electrostatic chuck 1111, as described above. The base 1110 is an electrically conductive member or includes an electrically conductive member therein. At least one bias power supply, such as the second RF generator 31b and / or the bias DC generator 32a, is electrically coupled to the base 1110 (or its conductive member). The at least one bias power supply is configured to generate an electrical bias to attract ions from the plasma to the substrate W on the substrate support 11. The electrical bias includes a sequence of bias RF signals and / or voltage pulses as described above.

[0030] The electrostatic chuck 1111 is disposed on a base 1110. The electrostatic chuck 1111 includes a first portion P1 and a second portion P2. The first portion P1 has a substrate support surface (i.e., a central region 111a) as its upper surface. The first portion P1 and the substrate support surface have a substantially circular planar shape. The central axis of the first portion P1 and the substrate support surface is the central axis of the substrate support part 11. The first portion P1 includes the electrostatic electrode 1111b described above. When a DC voltage is applied from a DC power supply to the electrostatic electrode 1111b, an electrostatic attractive force is generated between the first portion P1 and the substrate W. The first portion P1 holds the substrate W by the generated electrostatic attractive force.

[0031] The second part P2 extends in the circumferential direction around the central axis of the substrate support 11 so as to surround the first part P1. The second part P2 has a ring support surface (i.e., annular region 111b) as its upper surface. The second part P2 and the ring support surface have a substantially annular planar shape. The second part P2 may include at least one electrostatic electrode. The second part P2 may include electrodes BEa and BEb as the at least one electrostatic electrode. The electrodes BEa and BEb constitute a bipolar electrode. A voltage is applied from at least one power supply to the electrodes BEa and BEb so as to generate a potential difference between them. This generates an electrostatic attractive force between the edge ring UR and the second part P2. The second part P2 holds the edge ring UR by the generated electrostatic attractive force.

[0032] In one embodiment, the ring support surface extends below the substrate support surface. In this case, the first portion P1 includes a sidewall surface 111s extending between the substrate support surface and the ring support surface. In this case, an edge ring LR (lower edge ring) may be disposed along the sidewall surface 111s and on the ring support surface. The edge ring LR forms part of the ring assembly 112. The edge ring LR may be made of a conductive material such as silicon, silicon carbide, tungsten, etc. Alternatively, the edge ring LR may be made of an insulating material such as quartz, etc. In this case, the edge ring UR is disposed on the edge ring LR. The ring support surface and the sidewall surface 111s are protected by the edge ring LR.

[0033] 3, the substrate support 11 may further include a cover ring CR and an insulating member IM. The insulating member IM is made of an insulating material such as quartz and has a generally cylindrical shape. The insulating member IM extends in the circumferential direction around the central axis of the substrate support 11 so as to surround the base 1110 and the electrostatic chuck 1111. The cover ring CR has a generally disk shape and is disposed on the insulating member IM so as to surround the edge ring UR.

[0034] The plasma processing apparatus 1 further includes a lift mechanism 50. The lift mechanism 50 includes a conductive ring 51, at least one rod 52, an actuator 53, and at least one connecting member .

[0035] The conductive ring 51 is formed of a metal or conductive material such as aluminum, and has a substantially ring shape. The conductive ring 51 extends in a circumferential direction around the central axis of the substrate support 11 so as to surround the base 1110 and the electrostatic chuck 1111 inside the insulating member IM. The conductive ring 51 is configured to be electrically coupled to the edge ring UR while supporting the edge ring UR placed thereon. That is, the conductive ring 51 is configured to be conductively or capacitively coupled to the edge ring UR while supporting the edge ring UR placed thereon. In the example of FIG. 3, the conductive ring 51 is conductive to the edge ring UR while supporting the edge ring UR placed thereon. Note that the exposed area on the surface of the conductive ring 51 may be covered with a film resistant to plasma. This film may be formed of a material such as an aluminum oxide film or yttrium fluoride, and may be formed by a method such as anodizing or thermal spraying.

[0036] The at least one rod 52 extends in the vertical direction below the conductive ring 51. The at least one rod 52 may have insulating properties. In this case, it is possible to suppress the electric bias from flowing into the actuator 53 via the at least one rod 52. In one embodiment, the lift mechanism 50 may include a plurality of rods 52 as the at least one rod 52. The plurality of rods 52 are arranged along the circumferential direction around the central axis of the substrate support 11. The plurality of rods 52 may be arranged at equal intervals along the circumferential direction.

[0037] The actuator 53 is disposed below the at least one rod 52 and is connected to the at least one rod 52. The actuator 53 is configured to move the edge ring up and down via the at least one rod 52 and the conductive ring 51. The actuator 53 may be, for example, a pneumatic or hydraulic cylinder, or a motor.

[0038] The at least one connecting member 54 provides an electrical connection between the conductive ring 51 and the base 1110 (or a conductive member thereof). The at least one connecting member 54 is configured to maintain the electrical connection in response to movement of the conductive ring 51. The at least one connecting member 54 may be configured to be deformable in response to movement of the conductive ring 51. Note that when the lift mechanism 50 includes a plurality of rods 52, the at least one connecting member 54 may include a plurality of connecting members 54.

[0039] In the example shown in Fig. 3, at least one connecting member 54 includes an upper portion 54a, a deformed portion 54b, and a lower portion 54c. The upper portion 54a, the deformed portion 54b, and the lower portion 54c are formed of a conductive material. The upper portion 54a is disposed directly below the conductive ring 51 and is fixed to the conductive ring 51. The upper portion 54a is electrically connected to the conductive ring 51. The lower portion 54c is disposed below the upper portion 54a and is fixed to the base 1110. The lower portion 54c is electrically connected to the base 1110.

[0040] The deformation portion 54b extends between the upper portion 54a and the lower portion 54c. The upper end of the deformation portion 54b is fixed to the upper portion 54a, and the lower end of the deformation portion 54b is fixed to the lower portion 54c. The deformation portion 54b is electrically connected to the upper portion 54a and the lower portion 54c. The deformation portion 54b may be a bellows as shown in FIG. 3.

[0041] At least one rod 52 penetrates the lower portion 54c, passes through the deformed portion 54b, and extends to a region immediately below the upper portion 54a. When the at least one rod 52 is moved upward by the actuator 53, the edge ring UR is moved upward via the upper portion 54a and the conductive ring 51 (see FIG. 23). The edge ring UR is moved upward in accordance with a decrease in its thickness in order to reduce the difference between the upper end position of the plasma sheath on the substrate W and the upper end position of the plasma sheath on the edge ring UR. In the plasma processing apparatus 1, even if the edge ring UR is moved upward from the electrostatic chuck 1111, the connection member 54 maintains the electrical connection between the base 1110 and the edge ring UR. In the plasma processing apparatus 1, since the edge ring UR is not in an electrically floating state, the edge ring UR can exert a function of reducing the difference between the upper end position of the plasma sheath on the substrate W and the upper end position of the plasma sheath on the edge ring UR.

[0042] The connecting member 54 may be a cylindrical member having a plurality of slits formed in its side wall surface so as to be elastically deformable in the longitudinal direction. For example, the connecting member 54 may be a flexure.

[0043] Reference is now made to Fig. 4, which illustrates a substrate support and lift mechanism of another exemplary embodiment. The substrate support 11 and lift mechanism 50 illustrated in Fig. 4 may be employed in the plasma processing apparatus 1. The embodiment of Fig. 4 will be described below in terms of differences from the embodiment of Fig. 3.

[0044] As shown in FIG. 4, the lift mechanism 50 may have a deformation portion 54b that is a contact band instead of a bellows. The upper end of the deformation portion 54b may be fixed to the conductive ring 51. The lower end of the deformation portion 54b may be fixed to the base 1110. The deformation portion 54b shown in FIG. 4 has flexibility in the vertical direction. As shown in FIG. 4, the deformation portion 54b may have a substantially arc shape that bulges outward. In this case, the insulating member IM may provide a recess in which a part of the deformation portion 54b is disposed.

[0045] Reference will now be made to FIG. 5. FIG. 5 is a diagram showing a substrate processing system according to an exemplary embodiment. The substrate processing system PS shown in FIG. 5 includes a transfer module TM, a plurality of process modules PM1 to PM7 (a plurality of substrate processing modules), and a controller MC. The substrate processing system PS may further include pedestals LPa to LPd, containers FUa to FUd, a loader module LM, an aligner AN, a load lock module LL1, a load lock module LL2, and a stocker module RSM (ring stocker). The number of pedestals, containers, and load lock modules in the substrate processing system PS may be any number equal to or greater than one. The number of process modules in the substrate processing system PS may be any number equal to or greater than two.

[0046] The stages LPa to LPd are arranged along one edge of the loader module LM. The containers FUa to FUd are mounted on the stages LPa to LPd, respectively. Each of the containers FUa to FUd is, for example, a container called a FOUP (Front Opening Unified Pod). Each of the containers FUa to FUd is configured to accommodate a substrate W therein.

[0047] The loader module LM has a transfer chamber. The pressure in the transfer chamber of the loader module LM is set to atmospheric pressure. The loader module LM has a transfer robot LMR. The transfer robot LMR is controlled by a controller MC. The transfer robot LMR is configured to transfer a substrate W through the transfer chamber of the loader module LM. The transfer robot LMR can transfer the substrate W between each of the containers FUa to FUd and the aligner AN, between the aligner AN and each of the load lock modules LL1, LL2, and between each of the load lock modules LL1, LL2 and each of the containers FUa to FUd. The aligner AN is connected to the loader module LM. The aligner AN is configured to adjust (align) the position of the substrate W.

[0048] Each of the load lock modules LL1 and LL2 is connected between the transfer chamber of the loader module LM and the transfer chamber TC of the transfer module TM. Each of the load lock modules LL1 and LL2 provides a preliminary reduced pressure chamber. A gate valve is provided between each of the preliminary reduced pressure chambers of the load lock modules LL1 and LL2 and the transfer chamber of the loader module LM. Furthermore, a gate valve is provided between each of the preliminary reduced pressure chambers of the load lock modules LL1 and LL2 and the transfer chamber TC of the transfer module TM.

[0049] The transfer module TM has a transfer chamber TC (vacuum transfer chamber) and a transfer robot TR. The transfer chamber TC is configured to allow depressurization of the space inside. The transfer robot TR includes a pick TP (end effector). The transfer robot TR may include at least two picks TP. In the illustrated example, the transfer robot TR includes two picks TP. One of the two picks TP is provided above the other. The transfer robot TR is configured to transfer a substrate W placed on any one of the two picks TP via the transfer chamber TC. The transfer robot TR is controlled by a controller MC.

[0050] The transfer module TM may be provided with position detection sensors S11 and S12. The position detection sensors S11 and S12 are provided on a transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM1. The position detection sensors S11 and S12 are used to correct the positions of the substrate W and the edge ring transferred from the transfer module TM to the process module PM1. The position detection sensors S11 and S12 are provided, for example, near a gate valve that separates the transfer module TM and the process module PM1. The position detection sensors S11 and S12 are arranged such that the distance between them is smaller than the outer diameter of the substrate W and smaller than the inner diameter of the edge ring. The transfer module TM may be provided with position detection sensors S21, S22, S31, S32, S41, S42, S51, S52, S61, S62, S71, and S72 in the same manner as the position detection sensors S11 and S12. The position detection sensors S21, S22 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM2. The position detection sensors S31, S32 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM3. The position detection sensors S41, S42 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM4. The position detection sensors S51, S52 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM5. The position detection sensors S61, S62 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM6. The position detection sensors S71, S72 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM7.

[0051] In one embodiment, the transport robot TR is configured to transport an edge ring for a substrate support of any one of the process modules PM1 to PM7. The edge ring is an edge ring UR or a ring set including an edge ring UR and an edge ring LR. The edge ring is placed on any one of the two picks TP and transported. Each pick TP has a sensor TS. The sensor TS is an optical sensor and configured to measure the position of a ring member such as an edge ring on the substrate support.

[0052] Each of the process modules PM1 to PM7 is an apparatus configured to perform a dedicated substrate processing, and includes a processing chamber (substrate processing chamber). A gate valve is provided between the processing chamber and the transfer chamber TC. At least one of the process modules PM1 to PM7 is a plasma processing apparatus 1.

[0053] The stocker module RSM (ring stocker) is connected to the transfer chamber TC via a gate valve. The stocker module RSM has a chamber and can accommodate multiple edge rings therein.

[0054] The controller MC is configured to control each part of the substrate processing system PS. The controller MC may be a computer including a processor, a storage device, an input device, a display device, etc. The controller MC executes a control program stored in the storage device and controls each part of the substrate processing system PS based on recipe data stored in the storage device.

[0055] A plasma processing apparatus 1 used as a process module of a substrate processing system PS may include a substrate support 11 as shown in any one of Figures 6 to 9. Each of Figures 6 to 9 illustrates a substrate support and a lift mechanism according to yet another exemplary embodiment. In each of the embodiments of Figures 6 to 9, an edge ring of the plasma processing apparatus 1 can be transferred by a transfer robot TR and replaced with a corresponding edge ring in a stocker module RSM.

[0056] 6, the substrate support 11 provides a plurality of through holes passing therethrough along a vertical direction. The plurality of through holes in the substrate support 11 are arranged along a circumferential direction around a central axis of the substrate support 11. The plurality of through holes in the substrate support 11 may be arranged at equal intervals. Additionally, the edge ring LR is formed with a plurality of through holes that are aligned with the plurality of through holes in the substrate support 11, respectively.

[0057] 6, the edge ring UR can be lifted upward from the substrate support 11 by a lift mechanism 60. The lift mechanism 60 includes a plurality of lift pins 61 and an actuator 62. The plurality of lift pins 61 are inserted into a plurality of through holes in the substrate support 11, respectively. The actuator 62 is connected to the plurality of lift pins 61 and configured to move the plurality of lift pins 61 up and down.

[0058] When the lift pins 61 are moved upward by the actuator 62 with the upper ends of the lift pins 61 in contact with the edge ring UR, the edge ring UR is lifted upward from the substrate support 11. In this state, the transport robot TR moves the pick TP below the edge ring UR. Then, the edge ring UR is handed over to the pick TP as the lift pins 61 move downward. Thereafter, the edge ring UR is transported to the stocker module RSM by the transport robot TR.

[0059] Then, the replacement edge ring UR is transferred from the stocker module RSM into the chamber 10 by the transfer robot TR. Then, the multiple lift pins 61 are moved upward by the actuator 62, so that the edge ring UR is handed over to the multiple lift pins 61. Then, the pick TP moves to the outside of the chamber 10, and the multiple lift pins 61 move downward. As a result, the replacement edge ring UR is placed on the substrate support 11.

[0060] 7, the substrate support 11 provides a plurality of through holes passing therethrough along a vertical direction. The through holes of the substrate support 11 are arranged along a circumferential direction around a central axis of the substrate support 11. The through holes of the substrate support 11 may be arranged at equal intervals along the circumferential direction. The edge ring LR does not have a plurality of through holes aligned with the through holes of the substrate support 11.

[0061] 7, a ring set including the edge rings UR and LR can be lifted upward from the substrate support 11 by a lift mechanism 70. The lift mechanism 70 includes a plurality of lift pins 71 and an actuator 72. The plurality of lift pins 71 are inserted into a plurality of through holes in the substrate support 11, respectively. The actuator 72 is connected to the plurality of lift pins 71 and configured to move the plurality of lift pins 71 up and down.

[0062] When the multiple lift pins 71 are moved upward by the actuator 72 with the upper ends of the multiple lift pins 71 in contact with the edge ring LR, the ring set is lifted upward from the substrate support 11. In this state, the transport robot TR moves the pick TP below the ring set. Then, the multiple lift pins 71 move downward, whereby the ring set is handed over to the pick TP. Thereafter, the ring set is transported to the stocker module RSM by the transport robot TR.

[0063] Then, the replacement ring set is transferred from the stocker module RSM into the chamber 10 by the transfer robot TR. Then, the multiple lift pins 71 are moved upward by the actuator 72, and the ring set is handed over to the multiple lift pins 71. Then, the pick TP moves to the outside of the chamber 10, and the multiple lift pins 71 move downward. As a result, the replacement ring set is placed on the substrate support 11.

[0064] In the embodiment of FIG. 8, the conductive ring 51 extends to a region on the edge ring LR so as to support the edge ring UR by its upper inner edge. In the embodiment of FIG. 8, the outer ring OR is disposed on the conductive ring 51 so as to surround the edge ring UR. The outer ring OR may be formed of an insulating material such as quartz. In the embodiment of FIG. 8, similarly to the embodiment of FIG. 6, the substrate support 11 is provided with a plurality of through holes passing therethrough. The plurality of through holes of the substrate support 11 are arranged along the circumferential direction around the central axis of the substrate support 11. The plurality of through holes of the substrate support 11 may be arranged at equal intervals along the circumferential direction. In addition, the edge ring LR is formed with a plurality of through holes aligned with the plurality of through holes of the substrate support 11.

[0065] The operations of the lift mechanism 60 and the transport robot TR for replacing the edge ring UR in the embodiment of FIG. 8 are similar to the operations of the lift mechanism 60 and the transport robot TR for replacing the edge ring UR in the embodiment of FIG.

[0066] In the embodiment of FIG. 9, the edge ring LR has an outer diameter smaller than that of the edge ring UR. The edge ring UR is disposed on the edge ring LR such that its outer edge protrudes radially outward relative to the edge ring LR. The conductive ring 51 supports the outer edge of the edge ring UR by its upper end inner edge. In the embodiment of FIG. 9, an outer ring OR is disposed on the conductive ring 51 so as to surround the edge ring UR. The outer ring OR may be made of an insulating material such as quartz. Also, in the embodiment of FIG. 9, another outer ring BOR is disposed below the upper end of the conductive ring 51 so as to surround the edge ring LR. The outer ring BOR may be made of an insulating material such as quartz.

[0067] In the embodiment of Fig. 9, the substrate support 11 is provided with a plurality of through holes passing therethrough, similar to the embodiment of Fig. 7. The plurality of through holes in the substrate support 11 are arranged in a circumferential direction around the central axis of the substrate support 11. The plurality of through holes in the substrate support 11 may be equally spaced in the circumferential direction. The edge ring LR does not have a plurality of through holes that are aligned with the plurality of through holes in the substrate support 11.

[0068] The operations of the lift mechanism 70 and the transport robot TR for replacing the edge ring in the embodiment of FIG. 9 are similar to the operations of the lift mechanism 70 and the transport robot TR for replacing the edge ring in the embodiment of FIG.

[0069] In addition, in yet another exemplary embodiment, the plasma processing apparatus 1 may be configured to selectively replace only the edge ring UR and replace the above-mentioned ring set. For example, the plasma processing apparatus 1 may have both the lift mechanism 60 and the lift mechanism 70. In this case, the multiple lift pins 61 and the multiple lift pins 71 are alternately arranged along the circumferential direction. Above each of the multiple lift pins 71, no through-hole is formed in the edge ring LR. In this case, it is possible to selectively replace only the edge ring UR shown in FIG. 6 using the lift mechanism 60 and replace the ring set including the edge ring UR and the edge ring LR shown in FIG. 6 using the lift mechanism 70. Alternatively, it is possible to selectively replace only the edge ring UR shown in FIG. 9 using the lift mechanism 60 and replace the ring set including the edge ring UR and the edge ring LR shown in FIG. 9 using the lift mechanism 70.

[0070] A configuration example of a capacitively coupled plasma processing apparatus as another example of the plasma processing apparatus 1 will be described below. FIG. 10 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. The plasma processing apparatus 1 shown in FIG. 10 includes a substrate support 11 and a lift mechanism 50 of the plasma processing apparatus according to any one of the various exemplary embodiments described above. The plasma processing apparatus 1 shown in FIG. 10 may include the lift mechanism 60 and / or the lift mechanism 70 described above. The plasma processing apparatus 1 shown in FIG. 10 may be employed as a process module in a substrate processing system PS. The capacitively coupled plasma processing apparatus 1 shown in FIG. 10 will be described below from the viewpoint of differences from the inductively coupled plasma processing apparatus 1 shown in FIG. 2.

[0071] In the plasma processing apparatus 1 shown in FIG. 10, the gas introduction section includes a shower head 13A. The shower head 13A is disposed above a substrate support 11. In one embodiment, the shower head 13A constitutes at least a part of a ceiling of a plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13A, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 is grounded. The shower head 13A and the substrate support 11 are electrically insulated from a housing of the plasma processing chamber 10.

[0072] The shower head 13A is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13A has at least one gas supply port 13Aa, at least one gas diffusion chamber 13Ab, and multiple gas inlets 13Ac. The processing gas supplied to the gas supply port 13Aa passes through the gas diffusion chamber 13Ab and is introduced into the plasma processing space 10s from the multiple gas inlets 13Ac. The shower head 13A also includes at least one upper electrode. Note that the gas introduction unit may include, in addition to the shower head 13A, one or more side gas injectors (SGI) attached to one or more openings formed in the sidewall 10a.

[0073] In the plasma processing apparatus 1 shown in FIG. 10, a radio frequency power supply and / or at least one bias power supply are electrically coupled to the base 1110 (or a conductive member thereof), i.e., the lower electrode. The radio frequency power supply is a first RF generator 31a, which constitutes the plasma generating unit 12. The at least one bias power supply includes a second RF generator 31b and / or a bias DC generator 32a (i.e., a first DC generator). The at least one bias power supply is configured to generate an electric bias to attract ions from the plasma to the substrate W on the substrate support 11. The electric bias includes a sequence of bias RF signals and / or voltage pulses as described above.

[0074] In the plasma processing apparatus 1 shown in FIG. 10, the DC power supply 32 may further include a second DC generating unit 32b in addition to the bias DC generating unit 32a, i.e., the first DC generating unit 32a. In one embodiment, the first DC generating unit 32a is connected to at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to at least one lower electrode. In one embodiment, the second DC generating unit 32b is connected to at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to at least one upper electrode.

[0075] In various embodiments, in addition to the first DC signal, a second DC signal 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 of these pulse waveforms. In one embodiment, a waveform generator for generating a sequence of voltage pulses from a 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 a positive polarity or a negative polarity. Also, the sequence of voltage pulses may include one or more positive polarity voltage pulses and one or more negative polarity voltage pulses in one period. The first and second DC generating units 32a, 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided in place of the second RF generating unit 31b.

[0076] Reference is now made to Fig. 11. Fig. 11 is a diagram showing a substrate support and a lift mechanism according to yet another exemplary embodiment. The substrate support 11 and the lift mechanism 50 shown in Fig. 11 can be employed in the above-mentioned inductively coupled plasma processing apparatus 1 or the capacitively coupled plasma processing apparatus 1. The substrate support 11 and the lift mechanism 50 shown in Fig. 11 will be described below in terms of differences from the substrate support 11 and the lift mechanism 50 shown in Fig. 3.

[0077] 11 can electrically couple (e.g., conduct) the conductive ring 51 to the edge ring UR in a state where the edge ring UR on the conductive ring 51 is supported by the conductive ring 51, similarly to the lift mechanism 50 shown in FIG. 3. That is, the lift mechanism 50 shown in FIG. 11 can also form a first state in which the edge ring UR and the base 1110 are electrically coupled to each other (e.g., a conductive state between the edge ring UR and the base 1110). The lift mechanism 50 shown in FIG. 11 can also lower the conductive ring 51 downward via the rod 52 by the actuator 53, to separate the conductive ring 51 from the edge ring UR. That is, the lift mechanism 50 shown in FIG. 11 can form a second state in which the edge ring UR and the base 1110 are electrically separated from each other (e.g., a non-conductive state between the edge ring UR and the base 1110) by separating the conductive ring 51 from the edge ring UR. Therefore, the lift mechanism 50 shown in FIG. 11 constitutes a switch configured to be able to switch between a first state and a second state.

[0078] Reference is now made to Fig. 12. Fig. 12 is a diagram showing a substrate support and a lift mechanism according to yet another exemplary embodiment. The substrate support 11 and the lift mechanism 50 shown in Fig. 12 can be employed in the inductively coupled plasma processing apparatus 1 or the capacitively coupled plasma processing apparatus 1 described above. The substrate support 11 and the lift mechanism 50 shown in Fig. 12 will be described below in terms of differences from the substrate support 11 and the lift mechanism 50 shown in Fig. 4.

[0079] The plasma processing apparatus 1 including the lift mechanism 50 shown in FIG. 12 further includes a switch 56. The switch 56 may be a part of the lift mechanism 50. The switch 56 includes a switching element and is connected between the connection member 54 and the conductive ring 51 or between the connection member 54 and the base 1110. When the switching element of the switch 56 is in an ON state (closed state), a first state in which the edge ring UR and the base 1110 are electrically coupled to each other (e.g., a conductive state between the edge ring UR and the base 1110) is formed. When the switching element of the switch 56 is in an OFF state (open state), a second state in which the edge ring UR and the base 1110 are electrically isolated from each other (e.g., a non-conductive state between the edge ring UR and the base 1110) is formed.

[0080] Reference is now made to Fig. 13. Fig. 13 is a diagram showing a substrate support and a lift mechanism according to yet another exemplary embodiment. The substrate support 11 and the lift mechanism 50 shown in Fig. 13 can be employed in the above-mentioned inductively coupled plasma processing apparatus 1 or the capacitively coupled plasma processing apparatus 1. The substrate support 11 and the lift mechanism 50 shown in Fig. 13 will be described below in terms of differences from the substrate support 11 and the lift mechanism 50 shown in Fig. 6.

[0081] The plasma processing apparatus 1 including the lift mechanism 50 shown in FIG. 13 includes a lift mechanism 60 as a switch configured to be able to switch between the first state and the second state described above. In the lift mechanism 60, all the lift pins 61 are made of an insulating material. When the lift mechanism 60 positions all the lift pins 61 so that the edge ring UR is supported on the conductive ring 51 and electrically connected to the conductive ring 51, the first state (e.g., a conductive state between the edge ring UR and the base 1110) is formed. When the lift mechanism 60 lifts the edge ring UR upward from the conductive ring 51 and separates it from the conductive ring 51, the second state (e.g., a non-conductive state between the edge ring UR and the base 1110) is formed.

[0082] 11 to 13, it is possible to switch between the above-mentioned first state and second state as necessary. The switch can be controlled by the control unit 2. Hereinafter, with reference to FIGS. 14 to 18, a plasma processing method performed in the plasma processing apparatus 1 including the switch shown in FIGS. 11 to 13 will be described.

[0083] Please refer to Fig. 14 and Fig. 15(a). Fig. 14 is a flow chart showing a plasma processing method according to one exemplary embodiment. Fig. 15(a) is a diagram showing an example of an imaging device used with a plasma processing apparatus according to various exemplary embodiments. In the plasma processing method shown in Fig. 14 (hereinafter referred to as "method MT"), an imaging device 80 shown in Fig. 15(a) may be used. The imaging device 80 may be disposed in an aligner AN. The imaging device 80 may be disposed in any location as long as it is capable of acquiring an image of the substrate W.

[0084] The method MT is performed in a state in which the substrate W is placed on the substrate support 11. The method MT starts with a step STa. In the step STa, the control unit 2 reads a recipe.

[0085] In the subsequent step STJ, the control unit 2 determines whether or not electrical coupling (e.g., conduction) between the edge ring UR and the base 1110 is necessary. In the step STJ, when the control unit 2 determines that the plasma density on the edge ring UR should be increased, the control unit 2 may determine that electrical coupling between the edge ring UR and the base 1110 is necessary. On the other hand, in the step STJ, when the control unit 2 determines that the plasma density on the edge ring UR should not be increased, the control unit 2 may determine that electrical coupling between the edge ring UR and the base 1110 is not necessary.

[0086] When the control unit 2 determines that the plasma density on the edge ring UR should be increased, it controls the switch to form a first state (e.g., a conductive state between the edge ring UR and the base 1110) in step STb. On the other hand, when the control unit 2 determines that the plasma density on the edge ring UR should not be increased, it controls the switch to form a second state (e.g., a non-conductive state between the edge ring UR and the base 1110) in step STc.

[0087] Next, step STd is performed. In step STd, the control unit 2 controls each unit of the plasma processing apparatus 1 to perform the plasma processing according to the above-mentioned recipe. When step STd is performed, if the edge ring UR and the base 1110 are electrically coupled to each other (for example, they are conductive to each other), the plasma density on the edge ring UR is increased by the source RF signal and / or the electric bias supplied from the base 1110 to the edge ring UR via the conductive ring 51.

[0088] For the purpose of the determination in the step STJ, the control unit 2 may obtain from the imaging device 80 an image of the upper surface of the substrate W that has been processed in the plasma processing device 1 using the same recipe as the substrate W placed on the substrate support 11 before. The control unit 2 may determine whether or not the density of the plasma on the edge ring UR should be increased according to this image. In one embodiment, in the step STd, a plurality of holes may be formed in the substrate W by the plasma processing based on the recipe. In this case, when the control unit 2 determines in the step STJ from the image obtained from the imaging device 80 that the circularity of the hole in the edge region and the upper surface of the substrate W is equal to or less than the threshold value, the control unit 2 performs the step STb. On the other hand, when the control unit 2 determines in the step STJ from the image obtained from the imaging device 80 that the circularity is greater than the threshold value, the control unit 2 performs the step STc. The circularity may be the ratio of the minimum width to the maximum width of the hole in the edge region and the upper surface of the substrate W.

[0089] Reference will now be made to FIG. 15B in conjunction with FIG. 14. FIG. 15B illustrates an example of a measuring device that may be used with a plasma processing apparatus according to various exemplary embodiments. In the method MT, a measuring device 82 illustrated in FIG. 15B may be used. The measuring device 82 is attached to a pick TP. The measuring device 82 is configured to measure a thickness of a deposit on the edge ring UR. The measuring device 82 may include an image sensor that captures an image of the edge ring UR, or may include other optical sensors that are configured to measure a thickness of a deposit on the edge ring UR.

[0090] The control unit 2 may determine whether or not to increase the density of the plasma on the edge ring UR, depending on the thickness of the deposits on the edge ring UR measured by the measuring device 82. In one embodiment, in the step STd, cleaning inside the chamber 10 is performed by a plasma process based on a recipe. In this case, when the control unit 2 determines in the step STJ that the thickness of the deposits on the edge ring UR measured by the measuring device 82 is equal to or greater than the threshold value, the control unit 2 performs the step STb. On the other hand, when the control unit 2 determines in the step STJ that the thickness of the deposits on the edge ring UR measured by the measuring device 82 is smaller than the threshold value, the control unit 2 performs the step STc. When the step STd is performed after the step STb, the density of the plasma on the edge ring UR is increased, and the removal of the deposits on the edge ring UR is promoted. In the cleaning in the step STd, O 2 A cleaning gas containing an oxygen-containing gas such as a gas or other gas may be used, and cleaning may be performed by plasma generated from the cleaning gas. In addition, during cleaning in step STd, no object may be placed on the central region 111a of the substrate support 11, and a dummy wafer may be placed on the central region 111a.

[0091] Reference is now made to Fig. 16. Fig. 16 is a flow chart showing a plasma processing method according to another exemplary embodiment. The plasma processing method shown in Fig. 16 (hereinafter referred to as "method MTA") starts with step STa similar to step STa of method MT. Method MTA is performed in a state where a substrate W is placed on a substrate support 11.

[0092] In the next process STAd, the control unit 2 selects the first process specified in the recipe. The recipe includes a plurality of processes, and the recipe specifies setting information regarding the electrical coupling (e.g., conduction) between the edge ring UR and the base 1110 for each process. The setting information is information that specifies the above-mentioned first state (e.g., a conductive state) or the second state (e.g., a non-conductive state).

[0093] In the subsequent process STAJ, the control unit 2 determines whether or not electrical coupling between the edge ring UR and the base 1110 is necessary based on setting information specified in the recipe for the selected process. If the control unit 2 determines that electrical coupling between the edge ring UR and the base 1110 is necessary in the process STAJ, it performs a process STb in the same manner as in the method MT. On the other hand, if the control unit 2 determines that electrical coupling between the edge ring UR and the base 1110 is not necessary in the process STAJ, it performs a process STc in the same manner as in the method MT. Then, the control unit 2 controls each unit of the plasma processing apparatus 1 to perform the process selected in the process STAe.

[0094] In the next step STAJb, the control unit 2 determines whether or not all steps included in the recipe have been completed. If the control unit 2 determines that all steps have not been completed, it selects the next step included in the recipe in step STAf and continues processing from step STAJ. On the other hand, if the control unit 2 determines that all steps have been completed in step STAJb, it ends the method MTA.

[0095] Reference will now be made to Figures 17 and 18. Figure 17 is a flow chart showing a plasma processing method according to yet another exemplary embodiment. Figure 18 is a diagram showing an example of a measuring device used with a plasma processing apparatus according to various exemplary embodiments. In the plasma processing method shown in Figure 17 (hereinafter referred to as "method MTB"), a measuring device 200 shown in Figure 18 can be used.

[0096] The measuring device 200 includes a condenser lens 202, an optical fiber 204, a light source 206, a photodetector 208, and a calculation unit 210. The condenser lens 202 is provided above the ceiling 10U of the chamber 10, and is optically coupled to the substrate W on the substrate support 11 via an optical window in the ceiling 10U. The ceiling 10U is the dielectric window 101 or the showerhead 13A.

[0097] The condenser lens 202 is optically connected to a light source 206 and a photodetector 208 (polychrometer) via an optical fiber 204. The light source 206 emits light Ls. The light Ls emitted from the light source 206 is irradiated onto the substrate W via the optical fiber 204 and the condenser lens 202. The light Ls is reflected at a plurality of points in the substrate W at different height positions, generating interference light Li. The interference light Li is input to the photodetector 208 via the condenser lens 202 and the optical fiber 204. The photodetector 208 is configured to detect the light intensity of the interference light Li. The calculation unit 210 is configured to measure the etching depth of the substrate W based on a change in the light intensity of the interference light Li detected by the photodetector 208. The light intensity of the interference light Li changes periodically according to the etching depth of the substrate W. Therefore, the calculation unit 210 can identify the etching depth of the substrate W from the change in the light intensity of the interference light Li.

[0098] 17, method MTB starts with step STa, which is similar to step STa of method MT. Method MTB is performed with the substrate W placed on the substrate support 11. In the subsequent step SBd, the control unit 2 starts plasma processing according to the recipe, specifically, plasma etching on the substrate W. In the plasma etching, the control unit 2 controls each part of the plasma processing apparatus 1 according to the recipe. At the start of plasma etching in step STBd, a second state (e.g., a non-conductive state between the edge ring UR and the base 1110) is formed.

[0099] Steps STBJ to STBJb are performed during the period in which the plasma etching started in step STBd is being performed. In step STBJ, the control unit 2 determines whether or not electrical coupling (e.g., conduction) between the edge ring UR and the base 1110 is necessary. Specifically, the control unit 2 determines whether or not the etching depth measured by the measuring device 200 has reached a threshold value. If the control unit 2 determines that the etching depth has reached the threshold value, it performs step STb. On the other hand, if the control unit 2 determines that the etching depth has not reached the threshold value, it performs step STc and maintains the second state (e.g., non-conductive state).

[0100] In the next step STBJb, it is determined whether or not to end the process started in step STd, i.e., plasma etching. If the plasma etching is not to be ended, the process from step STBJ is repeated. On the other hand, if the plasma etching is to be ended, the control unit 2 ends the method MTB.

[0101] Reference is now made to FIG. 19. FIG. 19 is a diagram illustrating an edge ring and a conductive ring according to yet another exemplary embodiment. As described above, in various exemplary embodiments, the conductive ring 51 may contact the edge ring UR and be electrically connected to the edge ring UR to form a conductive state between the edge ring UR and the base 1110 as the first state. Alternatively, as shown in FIG. 19, the conductive ring 51 may be electrically connected to the edge ring UR via a member 51c to form a conductive state between the edge ring UR and the base 1110 as the first state. The member 51c is made of a conductive material such as a metal. When the first state is formed, the member 51c is sandwiched between the edge ring UR and the conductive ring 51. The member 51c may have elasticity. The member 51c may be a diagonally wound coil spring.

[0102] Reference is now made to FIG. 20. FIG. 20 is a diagram showing an edge ring and a conductive ring according to yet another exemplary embodiment. The conductive ring 51 may form the first state by capacitively coupling to the edge ring UR. As shown in FIG. 20, the conductive ring 51 may include a dielectric region 51f on its upper surface. In this case, the conductive ring 51 capacitively couples to the edge ring UR while supporting the edge ring UR placed on the dielectric region 51f. The dielectric region 51f may be a film formed of a dielectric material. The dielectric region 51f may cover the surface of the conductive ring 51. The dielectric region 51f may be formed by thermal spraying of a material such as yttrium oxide.

[0103] Reference is now made to FIG. 21, which illustrates a substrate support and a lift mechanism according to yet another exemplary embodiment. In the various exemplary embodiments described above, the edge ring UR and the edge ring LR may have the structure illustrated in FIG. 21. As illustrated in FIG. 21, the edge ring LR includes an inner periphery LRi, a middle portion LRm, and an outer periphery LRo. The inner periphery LRi is ring-shaped and is disposed on the ring support surface along the side wall surface 111s. The edge region of the substrate W is located above the inner periphery LRi. The outer periphery LRo is ring-shaped and extends radially outward relative to the inner periphery LRi. The edge ring UR is disposed on the outer periphery LRo. The middle portion LRm is ring-shaped and extends between the inner periphery LRi and the outer periphery LRo. The middle portion LRm is interposed between the edge of the substrate W on the substrate support surface and the inner periphery of the edge ring UR. The position of the upper surface of the intermediate portion LRm in the height direction is higher than the position of the upper surface of the inner peripheral portion LRi in the height direction and the position of the upper surface of the outer peripheral portion LRo in the height direction. The intermediate portion LRm may have a thickness larger than the thickness of the inner peripheral portion LRi and the thickness of the outer peripheral portion LRo.

[0104] When the edge ring UR is disposed on the edge ring LR in contact with the edge ring LR, the edge ring UR exchanges heat with the base 1110 via the edge ring LR and the electrostatic chuck 1111. On the other hand, when the edge ring UR is lifted upward with respect to the edge ring LR, the temperature of the edge ring UR may rise. According to the intermediate portion LRm, as shown in FIG. 21, the inner peripheral surface of the edge ring UR is separated from the edge of the substrate W by a distance D in the radial direction. Therefore, even if the temperature of the edge ring UR rises, the temperature of the edge region of the substrate W is suppressed from rising. Also, when the edge ring UR shown in FIG. 21 is used, the difference between the upper end position of the plasma sheath on the substrate W and the upper end position of the plasma sheath on the edge ring UR can be reduced. As a result, ions can be supplied vertically to the edge region of the substrate W to vertically form a recess such as a hole in the edge region of the substrate W. The distance D may be 10 mm or less, 6 mm or less, or approximately 6 mm.

[0105] Hereinafter, the results of an experiment conducted to evaluate the embodiments shown in Fig. 3 and Fig. 21 will be described. In the experiment, plasma etching was performed on a silicon-containing film of a sample substrate using the plasma processing apparatus 1 shown in Fig. 10, and the angle of a hole formed in the silicon-containing film was obtained. The hole angle was 90° when the hole extended in the thickness direction, i.e., the vertical direction, of the sample substrate, was smaller than 90° when the hole was inclined toward the outside of the sample substrate, and was larger than 90° when the hole was inclined toward the center of the sample substrate.

[0106] FIG. 22 is a graph showing the results of the experiment. In FIG. 22, the horizontal axis indicates the driving amount of the conductive ring 51. In a state where the edge ring UR is in contact with the edge ring LR and is disposed on the edge ring LR, the driving amount is 0. As the edge ring UR is raised upward from the edge ring LR and the vertical distance between the edge ring UR and the edge ring LR is larger, the driving amount is larger. In FIG. 22, the vertical axis indicates the hole angle. In FIG. 22, the rectangular plot is the hole angle obtained when the edge ring UR that is not worn is used in the plasma processing apparatus 1 having the configuration shown in FIG. 3 and the driving amount is 0. In FIG. 22, the circular plot is the hole angle obtained when the edge ring UR that is 1 mm smaller in thickness than the edge ring UR that is not worn is used in the plasma processing apparatus 1 having the configuration shown in FIG. 3. In FIG. 22, the triangular plot is the hole angle obtained when the edge ring UR that is 1 mm smaller in thickness than the edge ring UR that is not worn and has a distance D of 6 mm is used in the plasma processing apparatus 1 having the configuration shown in FIG. 21. As shown in Fig. 22, it was confirmed that the hole angle can be adjusted according to the drive amount when the configuration of Fig. 21 is used, as in the case of using the configuration shown in Fig. 3. Furthermore, with the configuration of Fig. 21, the increase in the hole angle with respect to the increase in the drive amount was smaller than when using the configuration of Fig. 3. From this, it was confirmed that the configuration of Fig. 21 can obtain a high control resolution of the hole angle.

[0107] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. In addition, elements in different embodiments can be combined to form other embodiments.

[0108] For example, any one of the above-mentioned containers FUa to FUd may be used as the stocker module RSM.

[0109] Various exemplary embodiments included in the present disclosure are now described in [E1] to [E19] below.

[0110] [E1] A chamber; a substrate support disposed within the chamber; an edge ring having electrical conductivity and disposed to surround the substrate on the substrate support; a lift mechanism configured to move the edge ring up and down; A plasma generating unit including a high frequency power source and configured to generate plasma in the chamber; a bias power supply configured to generate an electrical bias to attract ions from the plasma to the substrate on the substrate support; Equipped with The substrate support includes: a base electrically coupled to the bias power supply and / or the high frequency power supply; an electrostatic chuck on the base; Including, The lift mechanism includes: a conductive ring that is electrically coupled to the edge ring while supporting the edge ring placed thereon; a rod extending vertically below the conductive ring; an actuator configured to move the edge ring up and down via the rod and the conductive ring; a connecting member providing an electrical connection between the conductive ring and the base, the connecting member being configured to maintain the electrical connection in response to movement of the conductive ring; and Including, Plasma processing equipment.

[0111] [E2] The plasma processing apparatus according to E1, wherein the connection member is deformable in response to movement of the conductive ring.

[0112] [E3] The plasma processing apparatus according to E2, wherein the connection member includes a bellows, a contact band, or a cylindrical member having a plurality of slits formed in a side wall surface thereof so as to be elastically deformable in the longitudinal direction.

[0113] [E4] The plasma processing apparatus according to any one of E1 to E3, wherein the rod has insulating properties.

[0114] [E5] The plasma processing apparatus according to any one of E1 to E4, wherein an exposed area on a surface of the conductive ring is covered with a film resistant to the plasma.

[0115] [E6] the edge ring is a top edge ring; The plasma processing apparatus further comprises a lower edge ring on which the upper edge ring is disposed; The electrostatic chuck comprises: a first portion having a substrate support surface; a second portion having a ring support surface extending below the substrate support surface and extending outwardly of the first portion; Including, the first portion includes a sidewall surface extending between the substrate support surface and the ring support surface; the lower edge ring is disposed along the sidewall surface and on the ring support surface. The plasma processing apparatus according to any one of E1 to E5.

[0116] [E7] The lower edge ring is an inner periphery disposed along the side wall surface; an outer periphery extending radially outwardly from the inner periphery and on which the upper edge ring is disposed; an intermediate portion extending between the inner periphery and the outer periphery and interposed between an edge of a substrate on the substrate support surface and an inner periphery of the upper edge ring; Including, The plasma processing apparatus according to E6.

[0117] [E8] The plasma processing apparatus of E6 or E7, wherein the lower edge ring is conductive.

[0118] [E9] The plasma processing apparatus according to E6 or E7, wherein the lower edge ring is insulating.

[0119] [E10] The plasma processing apparatus of any one of E6 to E9, further comprising a separate lift mechanism configured to lift the upper edge ring or a ring set including the upper edge ring and the lower edge ring from the electrostatic chuck.

[0120] [E11] The plasma processing apparatus of any one of E1 to E10, further comprising a switch configured to be able to switch between a first state in which the edge ring and the base are electrically coupled to each other and a second state in which the edge ring and the base are electrically isolated from each other.

[0121] [E12] The plasma processing apparatus of E11, wherein the lift mechanism is the switch and is configured to create the second state by lowering the conductive ring by the actuator so as to separate the conductive ring from the edge ring.

[0122] [E13] The plasma processing apparatus according to E11, wherein the switch includes a switching element connected between the connection member and the conductive ring or between the connection member and the base.

[0123] [E14] The plasma processing apparatus of E11, wherein the switch includes another lift mechanism configured to create the second state by lifting the edge ring off the conductive ring.

[0124] [E15] The plasma processing apparatus of E11, further comprising a control unit configured to control the switch to form the first state or the second state according to a loaded recipe.

[0125] [E16] a measurement device configured to measure an etch depth of a substrate on the substrate support; a controller configured to control the switch to switch from the second state to the first state when the etching depth measured by the measuring device reaches a threshold value; The plasma processing apparatus according to E11, further comprising:

[0126] [E17] E10, a plasma processing apparatus according to the present invention; a transfer module including a transfer chamber and a transfer robot connected to the plasma processing apparatus; a ring stocker configured to accommodate the upper edge ring or the upper edge ring and the ring set therein; A control unit; Equipped with The control unit controls the separate lift mechanism and the transfer robot to move the upper edge ring or the ring set in the chamber of the plasma processing apparatus to the Ring Stocker via the transfer chamber. Substrate processing system.

[0127] [E18] A plasma processing apparatus according to E11, an imaging device configured to capture an image of a substrate etched by the plasma processing device; A control unit; Equipped with the control unit is configured to control the switch to form the first state when etching the substrate later in the plasma processing apparatus when the circularity of a hole in an edge region of a previously processed substrate is equal to or less than a threshold value from the image of the substrate. Substrate processing system.

[0128] [E19] A plasma processing apparatus according to E11, a gage configured to measure a thickness of the edge ring deposit; and A control unit; Equipped with The control unit is configured to control the switch to form the second state when a thickness of the deposit is less than a threshold value during a cleaning process in the chamber, and to form the first state when a thickness of the deposit is equal to or greater than the threshold value. Substrate processing system.

[0129] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims. [Explanation of symbols]

[0130] 1...plasma processing apparatus, 10...chamber, 11...substrate support portion, 12...plasma generation portion, 1110...base, 1111...electrostatic chuck, 50...lift mechanism, 51...conductive ring, 52...rod, 53...actuator, 54...connection member, PS...substrate processing system, TM...transfer module, RSM...storage module, MC...control portion.

Claims

1. a chamber; a substrate support disposed within the chamber; an edge ring that is electrically conductive and that is disposed to surround the substrate on the substrate support; a lift mechanism configured to move the edge ring up and down; a plasma generating unit including a high frequency power source and configured to generate plasma within the chamber; a bias power supply configured to generate an electrical bias to attract ions from the plasma to the substrate on the substrate support; Equipped with The substrate support includes: a base electrically coupled to the bias power supply and / or the high frequency power supply; an electrostatic chuck on the base; Including, The lift mechanism includes: a conductive ring that supports the edge ring and is electrically coupled to the edge ring; a rod extending vertically below the conductive ring; an actuator configured to move the edge ring up and down via the rod and the conductive ring; a connecting member that provides an electrical connection between the conductive ring and the base, the connecting member being configured to maintain the electrical connection in response to movement of the conductive ring; Including, Plasma processing equipment.

2. The plasma processing apparatus according to claim 1 , wherein the connecting member is deformable in response to movement of the conductive ring.

3. 3. The plasma processing apparatus according to claim 2, wherein the connecting member includes a bellows, a contact band, or a cylindrical member having a plurality of slits formed in a sidewall surface thereof so as to be elastically deformable in the longitudinal direction.

4. 4. The plasma processing apparatus according to claim 1, wherein the rod has insulating properties.

5. 4. The plasma processing apparatus according to claim 1, wherein an exposed area on the surface of said conductive ring is covered with a film that is resistant to said plasma.

6. the edge ring is a top edge ring; The plasma processing apparatus further includes a lower edge ring on which the upper edge ring is disposed; The electrostatic chuck comprises: a first portion having a substrate support surface; a second portion having a ring support surface extending below the substrate support surface and extending outwardly of the first portion; Including, the first portion includes a sidewall surface extending between the substrate support surface and the ring support surface; the lower edge ring is disposed along the sidewall surface and on the ring support surface. The plasma processing apparatus according to any one of claims 1 to 3.

7. The lower edge ring is an inner periphery disposed along the side wall surface; an outer periphery extending radially outward from the inner periphery and on which the upper edge ring is disposed; an intermediate portion extending between the inner periphery and the outer periphery and interposed between an edge of a substrate on the substrate support surface and an inner periphery of the upper edge ring; Including, The plasma processing apparatus according to claim 6 .

8. The plasma processing apparatus of claim 6 , wherein the lower edge ring is electrically conductive.

9. The plasma processing apparatus of claim 6 , wherein the lower edge ring is insulating.

10. The plasma processing apparatus of claim 6 , further comprising a separate lift mechanism configured to lift the upper edge ring or a ring set including the upper edge ring and the lower edge ring from the electrostatic chuck.

11. A plasma processing apparatus as described in any one of claims 1 to 3, further comprising a switch configured to switch between a first state in which the edge ring and the base are electrically coupled to each other and a second state in which the edge ring and the base are electrically isolated from each other.

12. 12. The plasma processing apparatus of claim 11, wherein the lift mechanism is the switch and is configured to create the second state by lowering the conductive ring with the actuator so as to separate the conductive ring from the edge ring.

13. The plasma processing apparatus according to claim 11 , wherein the switch includes a switching element connected between the connection member and the conductive ring or between the connection member and the base.

14. The plasma processing apparatus of claim 11 , wherein the switch includes another lift mechanism configured to lift the edge ring from the conductive ring to create the second state.

15. The plasma processing apparatus of claim 11 , further comprising: a control unit configured to control the switch to form the first state or the second state according to a loaded recipe.

16. a measurement device configured to measure an etch depth of a substrate on the substrate support; a controller configured to control the switch to switch from the second state to the first state when the etching depth measured by the measuring device reaches a threshold value; The plasma processing apparatus of claim 11 further comprising:

17. The plasma processing apparatus according to claim 10; a transfer module including a transfer chamber and a transfer robot connected to the plasma processing apparatus; a ring stocker configured to accommodate the upper edge ring or the upper edge ring and the ring set therein; A control unit; Equipped with the control unit is configured to control the separate lift mechanism and the transfer robot to exchange the upper edge ring or the ring set in the chamber of the plasma processing apparatus with the upper edge ring or the ring set in the ring stocker via the transfer chamber. Substrate processing system.

18. The plasma processing apparatus according to claim 11; an imaging device configured to capture an image of a substrate etched by the plasma processing device; A control unit; Equipped with the control unit is configured to control the switch to form the first state when etching the substrate later in the plasma processing apparatus when the circularity of the hole in the edge region of the previously processed substrate is equal to or less than a threshold value from the image of the substrate. Substrate processing system.

19. The plasma processing apparatus according to claim 11; a measuring device configured to measure the thickness of the edge ring deposit; A control unit; Equipped with the control unit is configured to control the switch to establish the second state when the thickness of the deposit is smaller than a threshold value during the cleaning process in the chamber, and to establish the first state when the thickness of the deposit is equal to or greater than the threshold value. Substrate processing system.

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