Plasma processing apparatus and substrate processing system

Abstract

To provide a technique for reducing the difference between the top position of a plasma sheath on an edge ring and the top position of a plasma sheath on a substrate.SOLUTION: A plasma processing apparatus includes a chamber, a substrate support, an edge ring, a lifter, a plasma generator, and a bias power supply. The substrate support is disposed in the chamber. The lifter is configured to move the edge ring up and down with respect to the substrate support. The substrate support includes a base electrically coupled to the bias power supply and / or a radio-frequency power supply in the plasma generator, and an electrostatic chuck on the base. The lifter includes a conductive ring and a connector, and the conductive ring is electrically coupled to the edge ring while supporting the edge ring placed on the conductive ring. The connector is configured to maintain an electrical coupling between the conductive ring and the base in response to the movement of the edge ring and the conductive ring with the lifter.SELECTED DRAWING: Figure 3

Description

Technical Field

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

Background Art

[0002] A plasma processing apparatus is used for plasma processing on a substrate. The plasma processing apparatus includes a chamber and a substrate support part. The substrate support part is disposed in the chamber. The substrate support part includes a base and an electrostatic chuck. A bias power source for generating an electrical bias for drawing ions from the plasma to the substrate is connected to the base. The electrostatic chuck is configured to support the substrate and an edge ring surrounding the substrate. Patent Document 1 below discloses a plasma processing apparatus configured to move the edge ring up and down.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique for reducing the difference between the upper end position of the plasma sheath on the edge ring and the upper end position of the plasma sheath on the substrate.

Means for Solving the Problems

[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 generation unit, and a bias power supply. The substrate support is disposed within the chamber. The edge ring is conductive and is disposed to surround a substrate on the substrate support. The lift mechanism is configured to move the edge ring vertically. The plasma generation unit includes a high-frequency power supply and is configured to generate plasma within the chamber. The bias power supply is configured to generate an electrical bias to draw ions from the plasma to a 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 connection member. The conductive ring is electrically coupled to the edge ring while supporting the edge ring thereon. The rod extends vertically below the conductive ring. The actuator is configured to move the edge ring vertically via the rod and the conductive ring. The connection 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.

Advantages of the Invention

[0006] According to one exemplary embodiment, it is possible to reduce the difference between the upper end position of the plasma sheath on the edge ring and the upper end position of the plasma sheath on the substrate.

Brief Description of the Drawings

[0007]

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Modes for Carrying Out the Invention

[0008] Hereinafter, various exemplary embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts will be denoted 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 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 portion 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 discharge port for discharging gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 described later, and the gas discharge port is connected to an exhaust system 40 described later. The substrate support portion 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0010] The plasma generation unit 12 is configured to generate plasma from at least one process gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Also, various types of plasma generation units including an AC (alternating current) plasma generation unit and a DC (direct current) plasma generation unit may be used. In one embodiment, the AC signal (AC power) used in the AC plasma generation unit has a frequency within the range of 100 kHz to 10 GHz. Accordingly, the AC signal includes an RF (radio frequency) signal and a microwave signal. In one embodiment, the RF signal has a frequency within 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 processes described in the present disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 so as to execute the 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 is realized by, for example, 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 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 RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0012] Hereinafter, a configuration example of an inductively coupled plasma processing apparatus as an example of the plasma processing apparatus 1 will be described. FIG. 2 is a diagram for explaining a 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 unit 20, a power source 30, and an exhaust system 40. The plasma processing chamber 10 includes a dielectric window 101. Further, the plasma processing apparatus 1 includes a substrate support unit 11, a gas introduction unit, and an antenna 14. The substrate support unit 11 is disposed in 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, the side wall 102 of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 is grounded.

[0014] The substrate support unit 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. Accordingly, the central region 111a is also referred to as a substrate support surface for supporting the substrate W, and the annular region 111b is also referred to as a ring support surface for supporting the ring assembly 112.

[0015] 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 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. Also, 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 bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as a plurality of bias electrodes. Also, the electrostatic electrode 1111b may function as a bias electrode. Accordingly, the substrate support portion 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 ring is formed of a conductive material or an insulating material, and the cover ring is formed of an insulating material.

[0017] Further, the substrate support portion 11 may include a temperature control 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 control module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. Further, the substrate support portion 11 may include a heat transfer gas supply portion 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 portion is configured to introduce at least one process gas from the gas supply portion 20 into the plasma processing space 10s. In one embodiment, the gas introduction portion includes a central gas injector (CGI) 13. The central gas injector 13 is disposed above the substrate support portion 11 and attached to a central opening formed in the dielectric window 101. The central gas injector 13 has at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas introduction port 13c. The process 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 introduction port 13c. Note that the gas introduction portion may include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 102 in addition to or instead of the central gas injector 13.

[0019] 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 the corresponding gas source 21 to the gas introduction unit via the corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Further, the gas supply unit 20 may include at least one flow modulation device for modulating or pulsing the flow rate of at least one process gas.

[0020] 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 bias electrode and the antenna 14. Thereby, plasma is formed from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Also, by supplying a bias RF signal to at least one bias electrode, a bias potential is generated on the substrate W, and ions in the formed plasma can be drawn into the substrate W.

[0021] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is coupled to the antenna 14 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 generation 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 generation unit 31b is coupled to at least one bias electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generation 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] Also, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a bias DC generation unit 32a. In one embodiment, the bias DC generation unit 32a is connected to at least one bias electrode and is configured to generate a bias DC signal. The generated bias DC signal is applied to 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 pulse waveform that is rectangular, trapezoidal, triangular, or a combination thereof. In one embodiment, a waveform generation unit for generating a sequence of voltage pulses from a DC signal is connected between the bias DC generation unit 32a and at least one bias electrode. Thus, the bias DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. 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 generation unit 32a may be provided in addition to the RF power supply 31 or may be provided in place of the second RF generation unit 31b.

[0025] Antenna 14 includes one or more coils. In one embodiment, antenna 14 may include an outer coil and an inner coil arranged coaxially. In this case, RF power supply 31 may be connected to both the outer coil and the inner coil, or may be connected to either one of the outer coil and the inner coil. In the former case, the same RF generation unit may be connected to both the outer coil and the inner coil, or separate RF generation units may be separately connected to the outer coil and the inner coil.

[0026] The exhaust system 40 can be connected to, for example, the gas discharge 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] Hereinafter, refer to FIG. 3. FIG. 3 is a diagram showing a substrate support portion and a lift mechanism according to one exemplary embodiment. The substrate support portion 11 and the lift mechanism 50 shown in FIG. 3 can be employed in the plasma processing apparatus 1.

[0028] As described above, the substrate support portion 11 is configured to support the edge ring UR (upper edge ring). The edge ring UR is a part of the ring assembly 112. The edge ring UR is arranged so as to surround the substrate W on the substrate support portion 11. The edge ring UR is formed of a material having conductivity such as silicon, silicon carbide, tungsten, or the like.

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

[0030] The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a first portion P1 and a second portion P2. The first portion P1 has, as its upper surface, a substrate support surface (i.e., the central region 111a). 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 unit 11. The first portion P1 includes the above-described electrostatic electrode 1111b. When a DC voltage is applied from a DC power source to the electrostatic electrode 1111b, an electrostatic attraction is generated between the first portion P1 and the substrate W. The first portion P1 holds the substrate W by the generated electrostatic attraction.

[0031] The second portion P2 extends circumferentially around the central axis of the substrate support unit 11 so as to surround the first portion P1. The second portion P2 has, as its upper surface, a ring support surface (i.e., the annular region 111b). The second portion P2 and the ring support surface have a substantially annular planar shape. The second portion P2 may include at least one electrostatic electrode. The second portion P2 may include an electrode BEa and an electrode BEb as at least one electrostatic electrode. The electrode BEa and the electrode BEb constitute a bipolar electrode. A voltage is applied from at least one power source to the electrode BEa and the electrode BEb so that a potential difference occurs between them. Thereby, an electrostatic attraction is generated between the edge ring UR and the second portion P2. The second portion P2 holds the edge ring UR by the generated electrostatic attraction.

[0032] In one embodiment, the ring support surface extends at a position lower than the substrate support surface. In this case, the first portion P1 includes a side wall surface 111s that extends 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 side wall 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 formed of a conductive material such as silicon, silicon carbide, tungsten, or the like. Alternatively, the edge ring LR may be formed of an insulating material such as quartz. In this case, the edge ring UR is disposed on the edge ring LR. The ring support surface and the side wall surface 111s are protected by the edge ring LR.

[0033] As shown in FIG. 3, the substrate support portion 11 may further include a cover ring CR and an insulating member IM. The insulating member IM is formed of an insulating material such as quartz and has a substantially cylindrical shape. The insulating member IM extends circumferentially around the central axis of the substrate support portion 11 so as to surround the base 1110 and the electrostatic chuck 1111. The cover ring CR has a substantially 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 54.

[0035] The conductive ring 51 is formed of a metal such as aluminum or a conductive material and has a substantially ring shape. The conductive ring 51 extends circumferentially around the central axis of the substrate support portion 11 inside the insulating member IM so as to surround the base 1110 and the electrostatic chuck 1111. 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 electrically conductive 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 electrically conductive to the edge ring UR while supporting the edge ring UR placed thereon. Note that the region exposed on the surface of the conductive ring 51 may be covered with a film having resistance 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 spraying.

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

[0037] The actuator 53 is disposed below at least one rod 52 and is connected to at least one rod 52. The actuator 53 is configured to move the edge ring up and down through 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] At least one connecting member 54 provides an electrical connection between the conductive ring 51 and the base 1110 (or its conductive member). At least one connecting member 54 is configured to maintain the electrical connection in response to the movement of the conductive ring 51. At least one connecting member 54 may be configured to be deformable in response to the movement of the conductive ring 51. In addition, when the lift mechanism 50 includes a plurality of rods 52, it may include a plurality of connecting members 54 as at least one connecting member 54.

[0039] In the example shown in FIG. 3, at least one connecting member 54 includes an upper portion 54a, a deformable portion 54b, and a lower portion 54c. The upper portion 54a, the deformable 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 deformable portion 54b extends between the upper portion 54a and the lower portion 54c. The upper end of the deformable portion 54b is fixed to the upper portion 54a, and the lower end of the deformable portion 54b is fixed to the lower portion 54c. The deformable portion 54b is electrically connected to the upper portion 54a and the lower portion 54c. The deformable portion 54b may be a bellows as shown in FIG. 3.

[0041] At least one rod 52 passes through the lower part 54c, passes through the deformation part 54b, and extends to the region directly below the upper part 54a. When at least one rod 52 is moved upward by the actuator 53, the edge ring UR is moved upward through the upper part 54a and the conductive ring 51 (see FIG. 23). The edge ring UR is moved upward in accordance with the 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 when the edge ring UR is moved upward from the electrostatic chuck 1111, the electrical connection between the base 1110 and the edge ring UR is maintained by the connection member 54. In the plasma processing apparatus 1, since the edge ring UR does not become an electrically floating state, the edge ring UR can exhibit 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] Note that the connection member 54 may be a cylindrical member in which a plurality of slits are formed on its side wall surface so as to be elastically deformable in its longitudinal direction. For example, the connection member 54 may be a flexure.

[0043] Hereinafter, refer to FIG. 4. FIG. 4 is a diagram showing a substrate support portion and a lift mechanism according to another exemplary embodiment. The substrate support portion 11 and the lift mechanism 50 shown in FIG. 4 can be adopted in the plasma processing apparatus 1. Hereinafter, the embodiment of FIG. 4 will be described from the viewpoint of the differences with respect to the embodiment of FIG. 3.

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

[0045] Refer to FIG. 5 below. FIG. 5 is a diagram showing a substrate processing system according to one 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 control unit MC. The substrate processing system PS may further include bases LPa to LPd, containers FUa to FUd, a loader module LM, an aligner AN, load lock modules LL1 and LL2, and a stocker module RSM (ring stocker). Note that the number of bases, the number of containers, and the number of load lock modules in the substrate processing system PS can be any number of one or more. Also, the number of process modules in the substrate processing system PS can be any number of two or more.

[0046] The bases LPa to LPd are arranged along one edge of the loader module LM. The containers FUa to FUd are respectively mounted on the bases LPa to LPd. Each of the containers FUa to FUd is a container called, for example, 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 the control unit MC. The transfer robot LMR is configured to transfer the 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 and LL2, and between each of the load lock modules LL1 and 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 perform alignment (position adjustment) 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 decompression chamber. A gate valve is provided between the preliminary decompression chamber of each of the load lock modules LL1 and LL2 and the transfer chamber of the loader module LM. Also, a gate valve is provided between the preliminary decompression chamber of each 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 such that the internal space can be decompressed. 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 through the transfer chamber TC. The transfer robot TR is controlled by a control unit 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 the 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, in the vicinity of the gate valve that partitions the transfer module TM and the process module PM1. The position detection sensors S11 and S12 are arranged such that, for example, the distance between them is smaller than the outer diameter of the substrate W and smaller than the inner diameter of the edge ring. Similar to the position detection sensors S11 and S12, the transfer module TM may be provided with position detection sensors S21, S22, S31, S32, S41, S42, S51, S52, S61, S62, S71, and S72. The position detection sensors S21 and S22 are provided on the transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM2. The position detection sensors S31 and S32 are provided on the transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM3. The position detection sensors S41 and S42 are provided on the transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM4. The position detection sensors S51 and S52 are provided on the transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM5. The position detection sensors S61 and S62 are provided on the transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM6. The position detection sensors S71 and S72 are provided on the transfer path of the substrate W and the edge ring from the transfer module TM to the process module PM7.

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

[0052] Each of the process modules PM1 to PM7 is a device configured to perform dedicated substrate processing and has 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 a plurality of edge rings therein.

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

[0055] The plasma processing apparatus 1 used as a process module of the substrate processing system PS may include a substrate support portion 11 shown in any one of FIGS. 6 to 9. Each of FIGS. 6 to 9 is a diagram showing a substrate support portion and a lift mechanism according to still another exemplary embodiment. In each of the embodiments of FIGS. 6 to 9, the edge ring of the plasma processing apparatus 1 can be transported by the transfer robot TR and exchanged with the corresponding edge ring in the stocker module RSM.

[0056] In the embodiment of FIG. 6, the substrate support portion 11 provides a plurality of through holes penetrating therethrough along the vertical direction. The plurality of through holes of the substrate support portion 11 are arranged along the circumferential direction around the central axis of the substrate support portion 11. The plurality of through holes of the substrate support portion 11 may be arranged at equal intervals. Further, a plurality of through holes aligned with the plurality of through holes of the substrate support portion 11 are formed in the edge ring LR.

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

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

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

[0060] In the embodiment of FIG. 7, the substrate support portion 11 provides a plurality of through holes penetrating therethrough along the vertical direction. The plurality of through holes of the substrate support portion 11 are arranged along the circumferential direction around the central axis of the substrate support portion 11. The plurality of through holes of the substrate support portion 11 may be arranged at equal intervals along the circumferential direction. The edge ring LR is not formed with a plurality of through holes respectively aligned with the plurality of through holes of the substrate support portion 11.

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

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

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

[0064] In the embodiment of FIG. 8, conductive ring 51 extends up to the area on edge ring LR so as to support edge ring UR by its upper end inner edge. In the embodiment of FIG. 8, outer ring OR is disposed on conductive ring 51 so as to surround edge ring UR. Outer ring OR can be formed of an insulating material such as quartz. Also in the embodiment of FIG. 8, similar to the embodiment of FIG. 6, substrate support 11 provides a plurality of through holes penetrating therethrough. The plurality of through holes of substrate support 11 are arranged along the circumferential direction around the central axis of substrate support 11. The plurality of through holes of substrate support 11 may be arranged at equal intervals along the circumferential direction. Further, a plurality of through holes are formed in edge ring LR that are aligned with the plurality of through holes of substrate support 11, respectively.

[0065] The operations of lift mechanism 60 and transfer robot TR for replacing edge ring UR in the embodiment of FIG. 8 are the same as the operations of lift mechanism 60 and transfer robot TR for replacing edge ring UR in the embodiment of FIG. 6.

[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 arranged such that its outer edge portion protrudes radially outward with respect to the edge ring LR on the edge ring LR. The conductive ring 51 supports the outer edge portion of the edge ring UR by its upper end inner edge portion. In the embodiment of FIG. 9, the outer ring OR is arranged 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 or the like. Also, in the embodiment of FIG. 9, another outer ring BOR is arranged below the upper end portion of the conductive ring 51 so as to surround the edge ring LR. The outer ring BOR may be formed of an insulating material such as quartz or the like.

[0067] Also in the embodiment of FIG. 9, the substrate support portion 11 provides a plurality of through holes penetrating therethrough, similarly to the embodiment of FIG. 7. The plurality of through holes of the substrate support portion 11 are arranged along the circumferential direction around the central axis of the substrate support portion 11. The plurality of through holes of the substrate support portion 11 may be arranged at equal intervals along the circumferential direction. The edge ring LR is not formed with a plurality of through holes that are respectively aligned with the plurality of through holes of the substrate support portion 11.

[0068] The operations of the lift mechanism 70 and the transfer robot TR for replacing the edge ring in the embodiment of FIG. 9 are the same as the operations of the lift mechanism 70 and the transfer robot TR for replacing the edge ring in the embodiment of FIG. 7.

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

[0070] Next, a configuration example of a capacitively coupled plasma processing apparatus as another example of the plasma processing apparatus 1 will be described. FIG. 10 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. Note that the plasma processing apparatus 1 shown in FIG. 10 includes the substrate support portion 11 and the lift mechanism 50 of the plasma processing apparatus according to any of the above-described various exemplary embodiments. The plasma processing apparatus 1 shown in FIG. 10 may include the above-described lift mechanism 60 and / or lift mechanism 70. Further, the plasma processing apparatus 1 shown in FIG. 10 can be adopted as a process module in the substrate processing system PS. Hereinafter, the capacitively coupled plasma processing apparatus 1 shown in FIG. 10 will be described 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 unit includes a shower head 13A. The shower head 13A is disposed above the substrate support unit 11. In one embodiment, the shower head 13A constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13A, the side wall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 is grounded. The shower head 13A and the substrate support unit 11 are electrically insulated from the 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 a plurality of gas introduction ports 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 plurality of gas introduction ports 13Ac. Further, the shower head 13A includes at least one upper electrode. The gas introduction unit may include, in addition to the shower head 13A, one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

[0073] In the plasma processing apparatus 1 shown in FIG. 10, a high-frequency power source and / or at least one bias power source is electrically coupled to the base 1110 (or its conductive member), that is, the lower electrode. The high-frequency power source is the first RF generation unit 31a and constitutes the plasma generation unit 12. The at least one bias power source includes the second RF generation unit 31b and / or the bias DC generation unit 32a (i.e., the first DC generation unit). The at least one bias power source is configured to generate an electrical bias for attracting ions from the plasma to the substrate W on the substrate support unit 11. The electrical bias includes the bias RF signal and / or the sequence of voltage pulses described above.

[0074] In the plasma processing apparatus 1 shown in FIG. 10, the DC power supply 32 may further include a second DC generation unit 32b in addition to the bias DC generation unit 32a, that is, the first DC generation unit 32a. In one embodiment, the first DC generation unit 32a is connected to at least one lower electrode and is 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 generation unit 32b is connected to at least one upper electrode and is 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, the 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 pulse waveform that is rectangular, trapezoidal, triangular, or a combination thereof. In one embodiment, a waveform generation unit for generating a sequence of voltage pulses from the DC signal is connected between the first DC generation unit 32a and at least one lower electrode. Accordingly, the first DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. When the second DC generation unit 32b and the waveform generation unit constitute a voltage pulse generation unit, the voltage pulse generation unit 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 within one period. Note that the first and second DC generation units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generation unit 32a may be provided in place of the second RF generation unit 31b.

[0076] Refer to FIG. 11 below. FIG. 11 is a diagram showing a substrate support portion and a lift mechanism according to yet another exemplary embodiment. The substrate support portion 11 and the lift mechanism 50 shown in FIG. 11 can be employed in the inductively coupled plasma processing apparatus 1 or the capacitively coupled plasma processing apparatus 1 described above. Hereinafter, the substrate support portion 11 and the lift mechanism 50 shown in FIG. 11 will be described from the perspective of differences from the substrate support portion 11 and the lift mechanism 50 shown in FIG. 3.

[0077] Similar to the lift mechanism 50 shown in FIG. 3, the lift mechanism 50 shown in FIG. 11 can electrically couple (for example, conduct) the conductive ring 51 to the edge ring UR while supporting the edge ring UR on the conductive ring 51. That is, also in the lift mechanism 50 shown in FIG. 11, a first state in which the edge ring UR and the base 1110 are electrically coupled to each other (for example, a conductive state between the edge ring UR and the base 1110) can be formed. Further, the lift mechanism 50 shown in FIG. 11 can 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, in the lift mechanism 50 shown in FIG. 11, by separating the conductive ring 51 from the edge ring UR, a second state in which the edge ring UR and the base 1110 are electrically separated from each other (for example, a non-conductive state between the edge ring UR and the base 1110) can be formed. Therefore, the lift mechanism 50 shown in FIG. 11 constitutes a switch configured to be able to switch between the first state and the second state.

[0078] Refer to FIG. 12 below. FIG. 12 is a diagram showing a substrate support portion and a lift mechanism according to yet another exemplary embodiment. The substrate support portion 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. Hereinafter, the substrate support portion 11 and the lift mechanism 50 shown in FIG. 12 will be described from the perspective of differences from the substrate support portion 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 the ON state (closed state), a first state (for example, a conductive state between the edge ring UR and the base 1110) in which the edge ring UR and the base 1110 are electrically coupled to each other is formed. When the switching element of the switch 56 is in the OFF state (open state), a second state (for example, a non-conductive state between the edge ring UR and the base 1110) in which the edge ring UR and the base 1110 are electrically separated from each other is formed.

[0080] Hereinafter, refer to FIG. 13. FIG. 13 is a diagram showing a substrate support portion and a lift mechanism according to yet another exemplary embodiment. The substrate support portion 11 and the lift mechanism 50 shown in FIG. 13 can be adopted in the inductively coupled plasma processing apparatus 1 or the capacitively coupled plasma processing apparatus 1 described above. Hereinafter, the substrate support portion 11 and the lift mechanism 50 shown in FIG. 13 will be described from the viewpoint of the differences with respect to the substrate support portion 11 and the lift mechanism 50 shown in FIG. 6.

[0081] The plasma processing apparatus 1 including the lift mechanism 60 shown in FIG. 13 includes a lift mechanism 60 as a switch configured to be able to switch between the above-described first state and second state. In the lift mechanism 60, all the lift pins 61 are formed 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, a first state (for example, 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, a second state (for example, a non-conductive state between the edge ring UR and the base 1110) is formed.

[0082] According to the switch described with reference to FIGS. 11 to 13, it is possible to switch between the above-described 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] Refer to FIGS. 14(a) and 15(a). FIG. 14 is a flowchart showing a plasma processing method according to one exemplary embodiment. FIG. 15(a) is a diagram showing an example of an imaging device used together with plasma processing apparatuses according to various exemplary embodiments. In the plasma processing method (hereinafter referred to as "method MT") shown in FIG. 14, the imaging device 80 shown in FIG. 15(a) can be used. The imaging device 80 can be disposed inside the aligner AN. The imaging device 80 may be disposed at any location as long as it can acquire an image of the substrate W.

[0084] Method MT is performed with the substrate W placed on the substrate support portion 11. Method MT starts at step STa. In step STa, a recipe is read by the control unit 2.

[0085] In the subsequent step STJ, it is determined by the control unit 2 whether an electrical connection (for example, conduction) between the edge ring UR and the base 1110 is necessary. In step STJ, when the control unit 2 determines that the density of plasma on the edge ring UR should be increased, it may determine that an electrical connection between the edge ring UR and the base 1110 is necessary. On the other hand, in step STJ, when the control unit 2 determines that the density of plasma on the edge ring UR should not be increased, it may determine that an electrical connection between the edge ring UR and the base 1110 is not necessary.

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

[0087] Next, step STd is performed. In step STd, each part of the plasma processing apparatus 1 is controlled by the control unit 2 so as to perform plasma processing according to the above-described recipe. When the edge ring UR and the base 1110 are electrically coupled to each other (for example, when they are conductive with each other) while step STd is being performed, the source RF signal and / or the electrical bias supplied from the base 1110 to the edge ring UR via the conductive ring 51 increases the plasma density on the edge ring UR.

[0088] The control unit 2 may acquire, from the imaging device 80, an image of the upper surface of the substrate W that has been processed using the same recipe in the plasma processing apparatus 1 prior to the substrate W placed on the substrate support unit 11 for the determination in step STJ. 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 step STd, a plurality of holes may be formed in the substrate W by plasma processing based on the recipe. In this case, when the control unit 2 determines in step STJ that the roundness of the holes in the edge region of the substrate W and on the upper surface of the substrate W is equal to or less than the threshold value from the image acquired from the imaging device 80, it performs step STb. On the other hand, when the control unit 2 determines in step STJ that the roundness is greater than the threshold value from the image acquired from the imaging device 80, it performs step STc. Note that the roundness may be the ratio of the minimum width to the maximum width of the holes in the edge region of the substrate W and on the upper surface of the substrate W.

[0089] Hereinafter, refer to (b) of FIG. 15 together with FIG. 14. (b) of FIG. 15 is a diagram showing an example of a measuring instrument used together with a plasma processing apparatus according to various exemplary embodiments. In the method MT, the measuring instrument 82 shown in (b) of FIG. 15 may be used. The measuring instrument 82 is attached to the pick TP. The measuring instrument 82 is configured to measure the thickness of the deposit on the edge ring UR. The measuring instrument 82 may include an image sensor that acquires an image of the edge ring UR, or may include other optical sensors configured to measure the thickness of the deposit on the edge ring UR.

[0090] The control unit 2 may determine whether to increase the density of the plasma on the edge ring UR according to the thickness of the deposit on the edge ring UR measured by the measuring instrument 82. In one embodiment, in step STd, cleaning inside the chamber 10 is performed by plasma processing based on a recipe. In this case, when the control unit 2 determines in step STJ that the thickness of the deposit on the edge ring UR measured by the measuring instrument 82 is equal to or greater than the threshold value, step STb is performed. On the other hand, when the control unit 2 determines in step STJ that the thickness of the deposit on the edge ring UR measured by the measuring instrument 82 is less than the threshold value, step STc is performed. When step STd is performed after step STb, the density of the plasma on the edge ring UR increases, and the removal of the deposit on the edge ring UR is promoted. In the cleaning of step STd, a cleaning gas containing an oxygen-containing gas such as O2 gas or other gas may be used, and cleaning may be performed by the plasma generated from the cleaning gas. Further, during the cleaning of step STd, an object may not be placed on the central region 111a of the substrate support portion 11, or a dummy wafer may be placed on the central region 111a.

[0091] Refer to FIG. 16 below. FIG. 16 is a flowchart 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 the same step STa as in step STa of Method MT. Method MTA is performed with the substrate W placed on the substrate support portion 11.

[0092] In the subsequent step STAd, the control unit 2 selects the first step specified in the recipe. The recipe includes a plurality of steps, and in the recipe, setting information regarding the electrical connection (for example, conduction) between the edge ring UR and the base 1110 for each step is specified. The setting information is information specifying the above-described first state (for example, conduction state) or second state (for example, non-conduction state).

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

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

[0095] Refer to FIGS. 17 and 18 below. FIG. 17 is a flowchart showing a plasma processing method according to yet another exemplary embodiment. FIG. 18 is a diagram showing an example of a measuring instrument used together with a plasma processing apparatus according to various exemplary embodiments. In the plasma processing method (hereinafter referred to as "Method MTB") shown in FIG. 17, the measuring instrument 200 shown in FIG. 18 can be used.

[0096] The measuring instrument 200 includes a condenser lens 202, an optical fiber 204, a light source 206, a photodetector 208, and an arithmetic unit 210. The condenser lens 202 is provided above the top portion 10U of the chamber 10 and is optically coupled to the substrate W on the substrate support portion 11 through the optical window of the top portion 10U. Note that the top portion 10U is the dielectric window 101 or the shower head 13A.

[0097] The condenser lens 202 is optically connected to the light source 206 and the photodetector 208 (polychromator) through the 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 through the optical fiber 204 and the condenser lens 202. The light Ls is reflected at a plurality of locations in the substrate W where the height positions are different from each other, generating interference light Li. The interference light Li is input to the photodetector 208 through 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 arithmetic unit 210 is configured to measure the etching depth of the substrate W based on the 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 arithmetic unit 210 can specify the etching depth of the substrate W from the change in the light intensity of the interference light Li.

[0098] As shown in FIG. 17, method MTB starts with the same process STa as process STa of method MT. Method MTB is performed with the substrate W placed on the substrate support portion 11. In the subsequent step SBd, the control unit 2 starts plasma processing according to the recipe, specifically, plasma etching of the substrate W. The control unit 2 controls each part of the plasma processing apparatus 1 according to the recipe in the plasma etching. Note that at the start of the plasma etching in step STBd, a second state (for example, 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 when the plasma etching started in step STBd is being performed. In step STBJ, the control unit 2 determines whether an electrical connection (for example, conduction) between the edge ring UR and the base 1110 is required. Specifically, the control unit 2 determines whether the etching depth measured by the measuring instrument 200 has reached a threshold value. When the control unit 2 determines that the etching depth has reached the threshold value, it performs step STb. On the other hand, when the control unit 2 determines that the etching depth has not reached the threshold value, it performs step STc to maintain the second state (for example, the non-conductive state).

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

[0101] Refer to FIG. 19 below. FIG. 19 is a diagram showing 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 form a conductive state between the edge ring UR and the base 1110 as a first state by contacting the edge ring UR and being electrically connected to the edge ring UR. Alternatively, as shown in FIG. 19, the conductive ring 51 may form a conductive state between the edge ring UR and the base 1110 as a first state by being electrically connected to the edge ring UR via the member 51c. The member 51c is formed of a conductive material such as metal. The member 51c is sandwiched between the edge ring UR and the conductive ring 51 when the first state is formed. The member 51c may have elasticity. The member 51c may be a helical coil spring.

[0102] Refer to FIG. 20 below. 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 a 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 spraying a material such as yttrium oxide.

[0103] Refer to FIG. 21 below. FIG. 21 is a diagram showing a substrate support portion 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 shown in FIG. 21. As shown in FIG. 21, the edge ring LR includes an inner peripheral portion LRi, an intermediate portion LRm, and an outer peripheral portion LRo. The inner peripheral portion LRi is ring-shaped and is disposed along the side wall surface 111s on the ring support surface. The edge region of the substrate W is located above the inner peripheral portion LRi. The outer peripheral portion LRo is ring-shaped and extends radially outward with respect to the inner peripheral portion LRi. The edge ring UR is disposed on the outer peripheral portion LRo. The intermediate portion LRm is ring-shaped and extends between the inner peripheral portion LRi and the outer peripheral portion LRo. The intermediate portion LRm is interposed between the edge of the substrate W on the substrate support surface and the inner peripheral surface of the edge ring UR. The height-direction position of the upper surface of the intermediate portion LRm is higher than the height-direction position of the upper surface of the inner peripheral portion LRi and the height-direction position of the upper surface of the outer peripheral portion LRo. The intermediate portion LRm may have a thickness greater 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 in contact with the edge ring LR and disposed on 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 can 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 rise of the edge region of the substrate W is suppressed. 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, and a recess such as a hole can be formed vertically in the edge region of the substrate W. Note that the distance D may be 10 mm or less, may be 6 mm or less, or may be approximately 6 mm.

[0105] The results of the experiments conducted for the evaluation of the respective embodiments of FIGS. 3 and 21 will be described below. In the experiments, plasma etching of the silicon-containing film on the sample substrate was performed using the plasma processing apparatus 1 shown in FIG. 10, and the angle of the holes formed in the silicon-containing film was determined. The angle of the holes is 90° when the holes extend in the thickness direction of the sample substrate, that is, in the vertical direction, less than 90° when the holes are tilted outward from the sample substrate, and greater than 90° when the holes are tilted in the direction of the center of the sample substrate.

[0106] FIG. 22 is a graph showing the results of the experiments. In FIG. 22, the horizontal axis indicates the driving amount of the conductive ring 51. In the state where the edge ring UR is in contact with the edge ring LR and disposed on the edge ring LR, the driving amount is 0. The greater the distance along the vertical direction between the edge ring UR and the edge ring LR as the edge ring UR is lifted upward from the edge ring LR, the greater the driving amount. In FIG. 22, the vertical axis indicates the angle of the holes. The rectangular plots in FIG. 22 are the angles of the holes obtained when using the non-consumed edge ring UR in the plasma processing apparatus 1 having the configuration shown in FIG. 3 and with the driving amount being 0. The circular plots in FIG. 22 are the angles of the holes obtained when using an edge ring UR having a thickness 1 mm smaller than that of the non-consumed edge ring UR in the plasma processing apparatus 1 having the configuration shown in FIG. 3. The triangular plots in FIG. 22 are the angles of the holes obtained when using an edge ring UR having a thickness 1 mm smaller than that of the non-consumed edge ring UR in the plasma processing apparatus 1 having the configuration shown in FIG. 21 and having a distance D of 6 mm. As shown in FIG. 22, it was confirmed that when using the configuration of FIG. 21, similar to the case of using the configuration shown in FIG. 3, it is possible to adjust the angle of the holes according to the driving amount. Further, according to the configuration of FIG. 21, compared with the case of using the configuration of FIG. 3, the increase amount of the angle of the holes with respect to the increase in the driving amount was smaller. From this, it was confirmed that according to the configuration of FIG. 21, a high control resolution of the angle of the holes can be obtained.

[0107] Although the above-described various exemplary embodiments have been described, various additions, omissions, substitutions, and changes may be made without being limited to the above-described exemplary embodiments. Also, it is possible to form other embodiments by combining elements in different embodiments.

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

[0109] Here, various exemplary embodiments included in the present disclosure are described in the following [E1] to [E19].

[0110] [E1] A chamber, A substrate support portion disposed in the chamber, An edge ring having conductivity and disposed so as to surround a substrate on the substrate support portion, A lift mechanism configured to move the edge ring up and down, A plasma generation unit including a high-frequency power source and configured to generate plasma in the chamber, A bias power source configured to generate an electrical bias for drawing ions from the plasma to the substrate on the substrate support portion, Comprising, The substrate support portion, A base electrically coupled to the bias power source and / or the high-frequency power source, An electrostatic chuck on the base, Including, The lift mechanism, A conductive ring that electrically couples the edge ring while supporting the edge ring on which it is placed, A rod extending in the vertical direction below the conductive ring, An actuator configured to move the edge ring up and down via the rod and the conductive ring, A connection member that provides an electrical connection between the conductive ring and the base, and is configured to maintain the electrical connection in response to the movement of the conductive ring, and the connection member, including, A plasma processing apparatus.

[0111] [E2] The plasma processing apparatus according to E1, wherein the connection member is deformable in response to the 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 its side wall surface so as to be elastically deformable in its longitudinal direction.

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

[0114] [E5] The region exposed on the surface of the conductive ring is covered with a film having resistance to the plasma, and the plasma processing apparatus according to any one of E1 to E4.

[0115] [E6] The edge ring is an upper edge ring, The plasma processing apparatus further includes a lower edge ring on which the upper edge ring is disposed, The electrostatic chuck, a first portion having a substrate support surface, a second portion having a ring support surface extending at a position lower than the substrate support surface and extending outside the first portion, including, The first portion includes a side wall surface extending between the substrate support surface and the ring support surface, The lower edge ring is disposed along the side wall 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 has an inner peripheral portion disposed along the side wall surface, an outer peripheral portion that extends radially outward from the inner peripheral portion and on which the upper edge ring is disposed, and an intermediate portion that extends between the inner peripheral portion and the outer peripheral portion and is interposed between the edge of the substrate on the substrate support surface and the inner peripheral surface of the upper edge ring, and includes the plasma processing apparatus according to E6.

[0117] [E8] The plasma processing apparatus according to E6 or E7, wherein the lower edge ring has conductivity.

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

[0119] [E10] The plasma processing apparatus according to any one of E6 to E9, further comprising another 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 according to 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 separated from each other.

[0121] [E12] The plasma processing apparatus according to E11, wherein the lift mechanism is the switch, and is configured to form 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 switching device includes a switching element connected between the connection member and the conductive ring or between the connection member and the base, and the plasma processing apparatus according to E11.

[0123] [E14] The switching device includes another lift mechanism configured to form the second state by lifting the edge ring from the conductive ring, and the plasma processing apparatus according to E11.

[0124] [E15] The plasma processing apparatus according to E11 further includes a control unit configured to control the switching device to form the first state or the second state according to the loaded recipe.

[0125] [E16] A measuring instrument configured to measure the etching depth of a substrate on the substrate support portion, A control unit configured to control the switching device to switch from the second state to the first state when the etching depth measured by the measuring instrument reaches a threshold value, and the plasma processing apparatus according to E11 further includes the above.

[0126] [E17] The plasma processing apparatus according to E10, A transfer module including a transfer chamber and a transfer robot connected to the plasma processing apparatus, An upper edge ring or a ring stocker configured to be able to accommodate the upper edge ring and the ring set therein, A control unit, and includes, The control unit is configured to control the another 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 through the transfer chamber. A substrate processing system.

[0127] [E18] The plasma processing apparatus described in E11, an imaging device configured to acquire an image of a substrate etched by the plasma processing apparatus, a control unit, and is provided with, when the circularity of the holes in the edge region of the substrate is equal to or less than a threshold value from the image of the previously processed substrate, the control unit controls the switch so as to form the first state when etching the substrate later in the plasma processing apparatus. A substrate processing system.

[0128] [E19] The plasma processing apparatus described in E11, a measuring instrument configured to measure the thickness of the deposit of the edge ring, a control unit, and is provided with, when cleaning in the chamber, the control unit controls the switch so as to form the second state when the thickness of the deposit is less than the threshold value, and to form the first normal state when the thickness of the deposit is equal to or greater than the threshold value. A substrate processing system.

[0129] From the above description, it will be understood that the various embodiments of the present disclosure are described herein for the purpose of illustration and that various changes can 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, and the true scope and spirit are indicated by the appended claims.

Explanation of Signs

[0130] 1…Plasma processing apparatus, 10…Chamber, 11…Substrate support unit, 12…Plasma generation unit, 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…Stocking module, MC…Control unit.

Claims

[Claim 1] 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.

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