JP2023109136A - Plasma processing apparatus and abnormal discharge control method - Google Patents

Abstract

An object of the present invention is to suppress the occurrence of abnormal discharge. A plasma process is performed in the chamber. A mounting table is placed in the chamber, and the substrate and the ring assembly are mounted around the substrate. The fixing part is provided on the mounting table and fixes at least one of the substrate and the ring assembly to the mounting table. The heat transfer gas supply unit supplies heat transfer gas between the mounting table and at least one of the substrate and the ring assembly. The heat transfer gas exhaust section exhausts the heat transfer gas from between the mounting table and at least one of the substrate and the ring assembly. An RF power supply supplies an RF (Radio Frequency) signal for plasma generation into the chamber. When at least one of the substrate and the ring assembly is placed on the mounting table, the control unit adjusts the pressure of the heat transfer gas supplied from the heat transfer gas supply unit to plasma to the substrate before performing the plasma processing on the substrate. Control so that it is lower than during processing. [Selection drawing] Fig. 1

Description

The present disclosure relates to a plasma processing apparatus and an abnormal discharge suppression method.

Japanese Laid-Open Patent Publication No. 2002-100001 discloses a configuration in which a gas such as He, Ar, or Xe is supplied from a gas supply insulating boss to the rear surface of the focus ring. Further, Patent Document 1 discloses that the gas supply insulation boss is a portion that is likely to cause abnormal discharge due to the relatively high gas pressure.

U.S. Patent Application Publication No. 2008/0236751

The present disclosure provides technology for suppressing the occurrence of abnormal discharge.

A plasma processing apparatus according to one aspect of the present disclosure includes a chamber, a mounting table, a fixing section, a heat transfer gas supply section, a heat transfer gas exhaust section, an RF power supply, and a control section. The chamber is in which plasma processing is performed. A mounting table is placed in the chamber, and the substrate and the ring assembly are mounted around the substrate. The fixing part is provided on the mounting table and fixes at least one of the substrate and the ring assembly to the mounting table. The heat transfer gas supply unit supplies heat transfer gas between the mounting table and at least one of the substrate and the ring assembly. The heat transfer gas exhaust section exhausts the heat transfer gas from between the mounting table and at least one of the substrate and the ring assembly. An RF power supply supplies an RF (Radio Frequency) signal for plasma generation into the chamber. When at least one of the substrate and the ring assembly is placed on the mounting table, the control unit adjusts the pressure of the heat transfer gas supplied from the heat transfer gas supply unit to plasma to the substrate before performing the plasma processing on the substrate. Control so that it is lower than during processing.

According to the present disclosure, it is possible to suppress the occurrence of abnormal discharge.

FIG. 1 is a diagram showing an example of a schematic configuration of a plasma processing system according to an embodiment. FIG. 2 is a diagram illustrating an example of occurrence of abnormal discharge according to the embodiment. FIG. 3 is a diagram schematically showing an example of a state during seasoning according to a comparative example. FIG. 4 is a diagram schematically showing an example of a state during seasoning according to the embodiment. FIG. 5 is a diagram illustrating an example of the flow of removing impurities according to the embodiment. FIG. 6 is a diagram explaining an example of the processing order of the method for suppressing abnormal discharge according to the embodiment. FIG. 7 is a diagram illustrating another example of the flow of removing impurities according to the embodiment. FIG. 8 is a diagram explaining another example of the processing order of the method for suppressing abnormal discharge according to the embodiment.

Hereinafter, embodiments of a plasma processing apparatus and an abnormal discharge suppression method disclosed in the present application will be described in detail with reference to the drawings. Note that the present embodiment does not limit the disclosed plasma processing apparatus and method for suppressing abnormal discharge.

2. Description of the Related Art A plasma processing apparatus is known that performs plasma processing such as plasma etching on a substrate by reducing the pressure in the chamber. A plasma processing apparatus is provided with a mounting table in a chamber. A substrate is placed on the mounting table, and a ring assembly such as a focus ring is mounted so as to surround the substrate. A heat transfer gas such as helium is supplied between the substrate or ring assembly and the mounting table for heat transfer.

By the way, in a plasma processing apparatus, abnormal electrical discharge such as arcing may occur between the substrate or the ring assembly and the mounting table. Therefore, a technique for suppressing the occurrence of abnormal discharge is expected.

[Embodiment]
[Device configuration]
An example of the plasma processing apparatus of the present disclosure will be described. In the embodiments described below, a case where the plasma processing apparatus of the present disclosure is used as a plasma processing system having a system configuration will be described as an example. FIG. 1 is a diagram showing an example of a schematic configuration of a plasma processing system according to an embodiment.

A configuration example of the plasma processing system will be described below. FIG. 1 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a controller 2 . A capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10 , a gas supply section 20 , a power supply 30 and an exhaust system 40 . Further, the plasma processing apparatus 1 includes a substrate support section 11 and a gas introduction section. The gas introduction is configured to introduce at least one process gas into the plasma processing chamber 10 . The gas introduction section includes a showerhead 13 . A substrate support 11 is positioned within the plasma processing chamber 10 . The showerhead 13 is arranged above the substrate support 11 . In one embodiment, showerhead 13 forms at least a portion of the ceiling of plasma processing chamber 10 . The plasma processing chamber 10 has a plasma processing space 10 s defined by a showerhead 13 , side walls 10 a of the plasma processing chamber 10 and a substrate support 11 . The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s and at least one gas exhaust port for exhausting gas from the plasma processing space. Plasma processing chamber 10 is grounded. The showerhead 13 and substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10 .

The substrate support portion 11 includes a body portion 111 and a ring assembly 112 . The body portion 111 has a central region 111 a for supporting the substrate W and an annular region 111 b for supporting the ring assembly 112 . A wafer is an example of a substrate W; The annular region 111b of the body portion 111 surrounds the central region 111a of the body portion 111 in plan view. The substrate W is arranged on the central region 111 a of the main body 111 , and the ring assembly 112 is arranged on the annular region 111 b of the main body 111 so as to surround the substrate W on the central region 111 a 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. FIG.

The substrate support portion 11 has a fixing portion. The fixing portion fixes at least one of the substrate W and the ring assembly 112 . In this embodiment, the fixing section fixes at least one of the substrate W and the ring assembly 112 to the substrate supporting section 11 by electrostatic adsorption. In one embodiment, body portion 111 includes base 1110 and electrostatic chuck 1111 . Base 1110 includes a conductive member. A conductive member of the base 1110 can function as a bottom electrode. An electrostatic chuck 1111 is arranged on the base 1110 . The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. Ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. In this embodiment, the electrostatic chuck 1111 corresponds to the fixed part of the present disclosure. A voltage is applied to the electrostatic chuck 1111 from a DC power supply (not shown) when the substrate W and the ring assembly 112 are electrostatically attracted. The electrostatic chuck 1111 fixes the substrate W and the ring assembly 112 by electrostatic attraction. Note that another member 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 placed on the annular electrostatic chuck or the annular insulating member, or may be placed on both the electrostatic chuck 1111 and the annular insulating member. Also, at least one RF/DC electrode coupled to an RF (Radio Frequency) power source 31 and/or a DC (Direct Current) power source 32, which will be described later, may be arranged in the ceramic member 1111a. In this case, at least one RF/DC electrode functions as the bottom electrode. If a bias RF signal and/or a DC signal, described below, is applied to at least one RF/DC electrode, the RF/DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and at least one RF/DC electrode may function as a plurality of lower electrodes. Also, the electrostatic electrode 1111b may function as a lower electrode. Accordingly, the substrate support 11 includes at least one bottom electrode.

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 made of a conductive material or an insulating material, and the cover ring is made of an insulating material.

Also, the substrate supporter 11 may include a temperature control module configured to control 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 heaters, heat transfer media, channels 1110a, or combinations thereof. A heat transfer fluid, such as brine or gas, flows through flow path 1110a. In one embodiment, channels 1110 a are formed in base 1110 and one or more heaters are positioned in ceramic member 1111 a of electrostatic chuck 1111 . The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to the gap between the back surface of the substrate W and the central region 111a. Further, the substrate support section 11 may be configured such that the heat transfer gas is supplied from the heat transfer gas supply section to the gap between the back surface of the ring assembly 112 and the annular region 111b.

For example, a central region 111a of the substrate supporting portion 11 is formed with a gas supply port 111d for discharging heat transfer gas. Further, the annular region 111b of the substrate supporting portion 11 is formed with a gas supply port 111e for discharging heat transfer gas. The substrate supporting portion 11 is provided with supply channels 115a and 115b such as piping for supplying heat transfer gas. The supply channel 115a communicates with the gas supply port 111d. The supply channel 115b communicates with the gas supply port 111e. The supply channels 115 a and 115 b are connected to the gas supply section 116 . The gas supply unit 116 is configured to be capable of individually controlling the flow rate of a heat transfer gas such as helium (He) gas or hydrogen (H ₂ ) gas and supplying the gas to the supply channels 115a and 115b. Further, the gas supply unit 116 is configured to be able to exhaust the heat transfer gas from the supply passages 115a and 115b. The heat transfer gas supplied through the supply channel 115a is discharged from the gas supply port 111d and supplied to the space between the substrate W and the central region 111a. The heat transfer gas supplied through the supply channel 115b is discharged from the gas supply port 111e and supplied to the space between the ring assembly 112 and the annular region 111b. Also, the heat transfer gas supplied to the space between the substrate W and the central region 111a is exhausted through the supply channel 115a. Heat transfer gas supplied to the space between ring assembly 112 and annular region 111b is exhausted via supply channel 115b. The gas supply 116 corresponds to the heat transfer gas exhaust and heat transfer gas exhaust of the present disclosure. Note that the gas supply unit 116 may be configured by being divided into a portion that supplies the heat transfer gas and a portion that exhausts the heat transfer gas.

The showerhead 13 is configured to introduce at least one process gas from the gas supply 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas introduction ports 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s through a plurality of gas introduction ports 13c. Showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas introduction part may include one or more side gas injectors (SGI: Side Gas Injectors) attached to one or more openings formed in the side wall 10a.

Gas supply 20 may include at least one gas source 21 and at least one flow controller 22 . In one embodiment, gas supply 20 is configured to supply at least one process gas from respective gas sources 21 through respective flow controllers 22 to showerhead 13 . Each flow controller 22 may include, for example, a mass flow controller or a pressure controlled flow controller. Additionally, gas supply 20 may include one or more flow modulation devices that modulate or pulse the flow of at least one process gas.

Power supply 30 includes an RF power supply 31 coupled to plasma processing chamber 10 via at least one impedance match circuit. RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and/or at least one upper electrode. Thereby, plasma is formed from at least one processing gas supplied to the plasma processing space 10s. Accordingly, RF power source 31 may function as at least part of a plasma generator configured to generate a plasma from one or more process gases in plasma processing chamber 10 . Also, by supplying a bias RF signal to at least one lower electrode, a bias potential is generated in the substrate W, and ion components in the formed plasma can be drawn into the substrate W. FIG.

In one embodiment, the RF power supply 31 includes a first RF generator 31a and a second RF generator 31b. The first RF generator 31a is coupled to at least one lower electrode and/or at least one upper electrode via at least one impedance matching circuit to generate a source RF signal (source RF power) for plasma generation. configured as In one embodiment, the source RF signal has a frequency within the range of 10 MHz to 150 MHz. In one embodiment, the first RF generator 31a may be configured to generate multiple source RF signals having different frequencies. One or more source RF signals generated are provided to at least one bottom electrode and/or at least one top electrode.

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

Power supply 30 may also include a DC power supply 32 coupled to plasma processing chamber 10 . The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the at least one bottom electrode and configured to generate a first DC signal. A generated first bias DC signal is applied to at least one bottom electrode. In one embodiment, the second DC generator 32b is connected to the at least one top electrode and configured to generate a second DC signal. The generated second DC signal is applied to at least one top electrode.

In various embodiments, at least one of the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one bottom electrode and/or at least one top electrode. The voltage pulses may have rectangular, trapezoidal, triangular, or combinations thereof 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 the at least one bottom electrode. Therefore, 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 pulse may have a positive polarity or a negative polarity. Also, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses in one cycle. Note that the first and second DC generators 32a and 32b may be provided in addition to the RF power supply 31, and the first DC generator 32a may be provided instead of the second RF generator 31b. good.

The exhaust system 40 may be connected to a gas outlet 10e provided at the bottom of the plasma processing chamber 10, for example. Exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure regulating valve regulates the pressure in the plasma processing space 10s. Vacuum pumps may include turbomolecular pumps, dry pumps, or combinations thereof.

Controller 2 processes computer-executable instructions that cause plasma processing apparatus 1 to perform the various steps described in this disclosure. Controller 2 may be configured to control elements of plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the controller 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 implemented by, for example, a computer 2a. Processing unit 2a1 can be configured to perform various control operations by reading a program from 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, read from the storage unit 2a2 and executed by the processing unit 2a1. 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 RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), 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).

Next, a flow of performing plasma processing such as plasma etching on the substrate W by the plasma processing system according to the embodiment will be briefly described. The substrate W is placed on the substrate supporting portion 11 by a transport mechanism such as a transport arm (not shown). When performing plasma processing on the substrate W, the plasma processing apparatus 1 reduces the pressure in the plasma processing chamber 10 by the exhaust system 40 . The electrostatic chuck 1111 fixes the substrate W and the ring assembly 112 by electrostatic attraction. When the electrostatic chuck 1111 electrostatically attracts, the control unit 2 controls the power supply 30 to apply high-frequency power for attraction to the substrate supporting part 11 . For example, the control unit 2 controls the power supply 30 to apply high-frequency power to the substrate supporting unit 11 so that the electrostatic chuck 1111 can electrostatically attract the substrate W and the ring assembly 112 . The plasma processing apparatus 1 supplies the processing gas from the gas supply unit 20 and introduces the processing gas into the plasma processing chamber 10 from the shower head 13 . Then, the plasma processing apparatus 1 supplies at least one RF signal from the RF power source 31 to generate plasma in the plasma processing space 10s, and subjects the substrate W to plasma processing.

By the way, in the plasma processing apparatus 1 , a problem may occur between the substrate W or the ring assembly 112 and the substrate supporting portion 11 . For example, abnormal discharge such as arcing may occur between the substrate W or the ring assembly 112 and the substrate support portion 11 .

FIG. 2 is a diagram illustrating an example of occurrence of abnormal discharge according to the embodiment. FIG. 2 schematically shows an enlarged view of the vicinity of the substrate support 11 of the plasma processing chamber 10 . The substrate supporting portion 11 has a central region 111a on which the substrate W is mounted, and a ring assembly 112 on the annular region 111b so as to surround the substrate W. As shown in FIG. A gas supply port 111d is formed in the central region 111a of the substrate supporting portion 11 . A gas supply port 111 e is formed in the annular region 111 b of the substrate supporting portion 11 . The gas supply port 111d communicates with the supply channel 115a, and the heat transfer gas is supplied from the gas supply unit 116 through the supply channel 115a. The gas supply port 111e communicates with the supply channel 115b, and the heat transfer gas is supplied from the gas supply unit 116 via the supply channel 115b. The gas supply port 111 d and the gas supply port 111 e discharge the heat transfer gas supplied from the gas supply section 116 .

An annular band is provided along the outer periphery of the substrate W on the substrate support surface 111a, and the outer periphery of the substrate W is supported by the band. Further, dots (not shown) for supporting the substrate W are formed on the substrate supporting surface 111a. A space is formed between the substrate W and the central region 111a to allow the heat transfer gas to flow.

The annular region 111b is provided with annular bands along the inner and outer circumferences of the ring assembly 112, respectively, and supports the inner and outer circumferences of the ring assembly 112 with the bands. Also, dots (not shown) that support the ring assembly 112 are formed in the annular region 111b. A space is formed between the ring assembly 112 and the annular region 111b to allow the heat transfer gas to flow.

In the plasma processing apparatus 1, the ring assembly 112 is gradually consumed by plasma processing. Ring assembly 112 is replaced when worn. Moisture is attached to the ring assembly 112 to be replaced. In the plasma processing apparatus 1, when the ring assembly 112 is replaced, seasoning (start-up processing) for repeating plasma generation is performed in order to stabilize the state inside the plasma processing chamber 10, such as removing moisture. For example, when performing seasoning, the plasma processing apparatus 1 decompresses the inside of the plasma processing chamber 10 by the exhaust system 40 in the same manner as in plasma processing. The electrostatic chuck 1111 fixes the substrate W and the ring assembly 112 by electrostatic attraction. When the electrostatic chuck 1111 electrostatically attracts the substrate, the plasma processing apparatus 1 applies high-frequency power for attraction from the power supply 30 to the substrate supporting portion 11 . The plasma processing apparatus 1 supplies the processing gas from the gas supply unit 20 and introduces the processing gas into the plasma processing chamber 10 from the shower head 13 . The process gas may be similar to the plasma process or may be a specific type of gas for seasoning. Then, the plasma processing apparatus 1 supplies at least one RF signal from the RF power source 31 to generate plasma in the plasma processing space 10s to perform seasoning. In the seasoning, plasma is repeatedly generated until the inside of the plasma processing chamber 10 reaches a stable state. The seasoning is performed before the substrate W is subjected to plasma processing in the manufacturing process of manufacturing semiconductor devices. The seasoning may be performed by placing the substrate W such as a dummy wafer on the substrate supporting portion 11 .

However, during seasoning, residual moisture may cause abnormal discharge such as arcing between the ring assembly 112 and the substrate support 11 . For example, when the ring assembly 112 is replaced, abnormal electrical discharge such as arcing may occur in the vicinity of the gas supply port 111e or in the supply channel 115b.

Imperfections may also occur due to impurities adhering to the substrate W and the rear surface of the ring assembly 112 . For example, when the substrate W or ring assembly 112 is replaced, abnormal discharge such as arcing may occur near the gas supply port 111d, near the gas supply port 111e, and within the supply channels 115a and 115b.

Therefore, in the present embodiment, when at least one of the substrate W and the ring assembly 112 is replaced, the control unit 2 reduces the heat transfer gas supplied from the gas supply unit 116 before performing plasma processing on the substrate W. The pressure is controlled to be lower than when the substrate W is processed with plasma.

For example, when the ring assembly 112 is replaced, the control unit 2 adjusts the pressure of the heat transfer gas supplied from the gas supply unit 116 to between the substrate support unit 11 and the ring assembly 112 during seasoning. The power of the high-frequency power supplied from the power source 30 is controlled to be less than the time of plasma processing on the substrate W. FIG.

Further, when the substrate W or the ring assembly 112 is replaced, the control unit 2 controls the transmission between the replaced substrate W or the ring assembly 112 and the substrate supporting unit 11 before performing the plasma processing on the substrate W. The gas supply 116 is controlled to supply and exhaust hot gas at least once.

The amount of moisture removed from the silicon surface increases at 200°C or higher, and increases from 300°C to 400°C. Therefore, during seasoning, the temperature of the ring assembly 112 is preferably 200° C. or higher, more preferably 300° C. or higher. For example, during seasoning, the temperature of the ring assembly 112 is more preferably 300°C to 400°C.

Here, as a comparative example, when the plasma processing apparatus 1 performs seasoning, the pressure of the heat transfer gas supplied from the gas supply unit 116 and the power of the high frequency power supplied from the power source 30 are adjusted to the same values as during the plasma processing of the substrate W. Seasoning shall be carried out in the same way. In this case, the temperature of the ring assembly 112 can be sufficiently raised by the heat input from the plasma, so that the water adhering to the ring assembly 112 can be removed in a short time. FIG. 3 is a diagram schematically showing an example of a state during seasoning according to a comparative example. FIG. 3 schematically shows the state of the substrate supporting portion 11 in the vicinity of the annular region 111b. FIG. 3 shows a case where the pressure of the heat transfer gas supplied from the gas supply unit 116 and the power of the high-frequency power supplied from the power source 30 are the same as those for the plasma processing of the substrate W during seasoning. In FIG. 3, the temperature of the ring assembly 112 is 350 degrees Celsius. This causes a rapid release of moisture from the ring assembly 112 . However, due to the influence of moisture released from the ring assembly 112, abnormal electrical discharge such as arcing may occur near the gas supply port 111e or inside the supply channel 115b. Therefore, during seasoning, the power of the high-frequency power supplied from the power supply 30 may be lower than that during the plasma processing of the substrate W to suppress the occurrence of abnormal discharge. However, when the power of the high frequency power is lowered, the heat input from the plasma to the ring assembly 112 is lowered, and the temperature of the ring assembly 112 does not rise sufficiently. As a result, although the occurrence of abnormal discharge can be suppressed, the time required to remove the moisture is lengthened, and the seasoning time is lengthened.

Therefore, in the present embodiment, when the ring assembly 112 is replaced, the control unit 2 adjusts the pressure of the heat transfer gas supplied from the gas supply unit 116 between the substrate support unit 11 and the ring assembly 112 during seasoning to The power of the high-frequency power supplied from the power supply 30 is controlled to be lower than that during the plasma processing of the substrate W and below that during the plasma processing of the substrate W. FIG.

For example, the control unit 2 controls the pressure of the heat transfer gas supplied from the gas supply unit 116 to between the substrate support unit 11 and the ring assembly 112 to be 15 Torr or less during seasoning. For example, the control unit 2 controls the supply of the heat transfer gas from the gas supply unit 116 to a state in which the supply of the heat transfer gas is stopped, or the supply of the heat transfer gas is minimized to minimize the supply of the heat transfer gas. As a result, heat transfer from the substrate W to the annular region 111b of the substrate supporting portion 11 is reduced, and the temperature of the ring assembly 112 can be sufficiently raised even when the power of the high frequency power is lowered.

As described above, the amount of moisture removed from the surface of silicon increases at 200° C. or higher. During seasoning, the control unit 2 controls the power source 30 to supply high-frequency power with a power that is lower than that for the plasma processing of the substrate W and that raises the temperature of the substrate W to 200° C. or higher. For example, even if the pressure of the heat transfer gas is lowered, the power of the high-frequency power that causes the temperature of the substrate W to be 200° C. or higher is determined in advance by experiments or simulations. As an example, the power of the high-frequency power that makes the temperature of the substrate W 300° C. to 400° C. is obtained. The control unit 2 controls the power supply 30 to supply the high-frequency power obtained in advance. FIG. 4 is a diagram schematically showing an example of a state during seasoning according to the embodiment. FIG. 4 schematically shows the state of the substrate supporting portion 11 in the vicinity of the annular region 111b. In FIG. 4, during seasoning, the pressure of the heat transfer gas supplied from the gas supply unit 116 is lowered below that during the plasma processing of the substrate W, and the power of the high-frequency power supplied from the power source 30 is lowered below that during the plasma processing of the substrate W. shows the case. In FIG. 4, the temperature of the ring assembly 112 is 400.degree. As a result, water adhering to the ring assembly 112 can be removed in a short period of time. Also, by lowering the pressure of the heat transfer gas, it is possible to suppress the occurrence of abnormal discharge such as arcing near the gas supply port 111e and inside the supply flow path 115b.

In addition, as described above, imperfections may occur due to impurities adhering to the substrate W or the rear surface of the ring assembly 112 . For example, when the substrate W or ring assembly 112 is replaced, abnormal discharge such as arcing may occur near the gas supply port 111d, near the gas supply port 111e, and within the supply channels 115a and 115b.

Therefore, in the present embodiment, when the substrate W or the ring assembly 112 is replaced, the controller 2 separates the replaced substrate W or the ring assembly 112 and the substrate supporting portion 11 before performing the plasma processing on the substrate W. The gas supply unit 116 is controlled so that the heat transfer gas is supplied and exhausted at least once between . For example, the control unit 2 controls the gas supply unit 116 to alternately supply and exhaust the heat transfer gas a plurality of times. FIG. 5 is a diagram illustrating an example of the flow of removing impurities according to the embodiment. FIG. 5 schematically shows the state of the substrate supporting portion 11 in the vicinity of the annular region 111b. The upper side of FIG. 5 shows a state in which the heat transfer gas is supplied between the ring assembly 112 and the substrate support section 11 . The lower side of FIG. 5 shows the state in which the heat transfer gas between the ring assembly 112 and the substrate support 11 is exhausted. Impurities 120 adhere to the back surface of ring assembly 112 on the upper side of FIG. By evacuating the heat transfer gas to reduce the pressure of the heat transfer gas and lowering the pressure of the heat transfer gas below that during plasma processing of the substrate W, impurities 120 are supplied as shown in the lower portion of FIG. It flows into the channel 115b and is removed. Thereby, abnormal discharge such as arcing caused by the impurities 120 can be suppressed.

Next, the process flow of the method for suppressing abnormal discharge performed by the plasma processing apparatus 1 according to the embodiment will be described. FIG. 6 is a diagram explaining an example of the processing order of the method for suppressing abnormal discharge according to the embodiment. FIG. 6 shows the processing of the abnormal discharge suppression method applied to the suppression of abnormal discharge in the ring assembly 112 . The ring assembly 112 is mounted on the substrate supporting portion 11, for example, when the plasma processing apparatus 1 is newly started, maintenance of the plasma processing apparatus 1, replacement due to wear of the ring assembly 112, or the like. The plasma processing apparatus 1 performs seasoning of the ring assembly 112 when the ring assembly 112 is placed on the substrate support 11 . The process illustrated in FIG. 6 is performed when seasoning the ring assembly 112 .

The controller 2 controls the exhaust system 40 to reduce the pressure in the plasma processing chamber 10 (S10).

The controller 2 fixes the ring assembly 112 to the substrate support 11 (S11). For example, the control unit 2 controls a DC power supply (not shown) to apply a voltage to the electrostatic chuck 1111 , and controls the power supply 30 to apply high-frequency power for attraction from the power supply 30 to the substrate supporting unit 11 . , the ring assembly 112 is fixed to the substrate support 11 by electrostatic adsorption.

The control unit 2 controls the gas supply unit 116 to supply heat transfer gas between the ring assembly 112 and the substrate support unit 11 from the gas supply unit 116 (S12). The control unit 2 controls the gas supply unit 116 to exhaust the heat transfer gas between the ring assembly 112 and the substrate support unit 11 through the gas supply unit 116 (S13).

The control unit 2 determines whether the supply and exhaust of the heat transfer gas have been repeated a predetermined number of times (S14). The predetermined number of times is determined in advance by experiments or simulations as the number of times that the impurity 120 can be removed. If it has not been performed a predetermined number of times (S14: No), the process proceeds to S12 described above.

On the other hand, if it has been performed a predetermined number of times (S14: Yes), the controller 2 performs the process of removing moisture (S15). For example, the control unit 2 controls the gas supply unit 20 to supply the processing gas from the gas supply unit 20 and introduce the processing gas into the plasma processing chamber 10 from the shower head 13 . The control unit 2 also controls the gas supply unit 116 to lower the pressure of the heat transfer gas supplied from the gas supply unit 116 to between the substrate supporting unit 11 and the ring assembly 112 than when the substrate W is subjected to plasma processing. Further, the control unit 2 controls the power supply 30 so that the power of the high-frequency power supplied from the power supply 30 is set to the level lower than that for the plasma processing of the substrate W. FIG. For example, the control unit 2 controls the power supply 30 to supply an RF signal having power equal to or lower than that for the plasma processing of the substrate W and to raise the temperature of the substrate W to 200° C. or higher. Note that the control unit 2 may perform the processing of S15 in parallel with the processing of S12 and S13. Thereby, in the plasma processing apparatus 1 , plasma is generated in the plasma processing chamber 10 and moisture is removed from the ring assembly 112 .

As a result, the occurrence of abnormal electrical discharge such as arcing between the ring assembly 112 and the substrate supporting portion 11 can be suppressed.

In the above-described embodiment, the case where the process of the abnormal discharge suppression method is performed in the seasoning has been described as an example. However, it is not limited to this. The abnormal discharge suppression method may be performed when the substrate W is replaced. For example, impurities 120 adhering to the back surface of the substrate W may cause imperfections. Therefore, when the substrate W is replaced, the control unit 2 at least supplies and exhausts the heat transfer gas between the replaced substrate W and the substrate supporting unit 11 before performing the plasma processing on the substrate W. The gas supply unit 116 may be controlled to perform one time. FIG. 7 is a diagram illustrating another example of the flow of removing impurities according to the embodiment. FIG. 7 schematically shows the state of the vicinity of the central region 111a of the substrate supporting portion 11. As shown in FIG. The upper side of FIG. 7 shows the state in which the heat transfer gas is supplied between the substrate W and the substrate supporting portion 11 . The lower side of FIG. 7 shows a state in which the heat transfer gas between the substrate W and the substrate supporting portion 11 is exhausted. Impurities 120 are attached to the back surface of the substrate W on the upper side of FIG. By evacuating the heat transfer gas to lower the pressure of the heat transfer gas and lowering the pressure of the heat transfer gas below that during plasma processing of the substrate W, the impurities 120 are supplied as shown in the lower portion of FIG. It flows into the channel 115a and is removed. As a result, the impurities 120 adhering to the back surface of the substrate W can be removed, and abnormal discharge such as arcing caused by the impurities 120 can be suppressed.

FIG. 8 is a diagram explaining another example of the processing order of the method for suppressing abnormal discharge according to the embodiment. FIG. 8 shows the processing of the method for suppressing abnormal discharge according to the embodiment applied to the suppression of abnormal discharge on the substrate W. FIG. The substrate W is placed on the substrate supporting portion 11 when plasma processing is performed in the plasma processing apparatus 1, for example. When the substrate W is placed on the substrate supporting portion 11, the plasma processing apparatus 1 performs the processing shown in FIG. 8 before performing the plasma processing on the substrate W. As shown in FIG.

The controller 2 controls the exhaust system 40 to reduce the pressure in the plasma processing chamber 10 by the exhaust system 40 (S20).

The control unit 2 controls the gas supply unit 116 to introduce the processing gas from the gas supply unit 116 into the plasma processing chamber 10 (S21). For example, the control unit 2 controls the gas supply unit 116 to supply the processing gas from the gas supply unit 116 and introduce Ar gas into the plasma processing chamber 10 .

The control unit 2 controls the power supply 30 to supply an RF signal with a power lower than that during plasma processing of the substrate W from the RF power supply 31 into the plasma processing chamber 10 (S22). For example, the control unit 2 supplies a relatively low-power RF signal such as 300 W from the RF power supply 31 to the conductive member functioning as the lower electrode of the base 1110 to generate a weak plasma. Plasma is applied to the substrate W;

In the processing of S21, the case where the processing gas is Ar gas and the plasma of Ar gas is applied to the substrate W has been described. However, the gas type of the processing gas is not limited to this. The process gas may be, for example, a gas such as _O2 gas, _CF4 gas, _N2 gas. However, the processing gas is required to be a gas species that causes less undesirable effects such as etching on the substrate W and the inner wall of the plasma processing chamber 10 when the plasma generated by the gas is generated. In addition, the processing gas must be a gas that easily ignites plasma. Further, the optimum type of processing gas may change depending on what kind of processing the substrate W to be plasma-processed has undergone in the previous process. It is preferable to appropriately select the processing gas in consideration of these factors.

Here, the reason why the weak plasma is applied to the substrate W is as follows. The state of the substrate W to be plasma-processed is not uniform due to the state of processing in the previous process (for example, a film formation process such as CVD). For example, the substrate W may have charge stored therein. If a strong plasma acts on the substrate W while electric charges are accumulated inside, there is a high possibility that surface arcing or the like will occur. Therefore, weak plasma is applied to the substrate W before strong plasma is applied. When the weak plasma acts on the substrate W, the state of charges accumulated inside the substrate W is uniformly adjusted (initialized).

A weak plasma is applied to the substrate W while no DC voltage (HV) is applied to the electrostatic chuck 1111 . This makes it easier for the charges inside the substrate W to move.

The RF signal power for generating such weak plasma is about 0.15 W/cm 2 to 1.0 W/cm ² , for example, about 100 to 500 W. The time for applying the weak plasma to the substrate W is, for example, about 5 to 20 seconds.

The controller 2 fixes the substrate W to the substrate support 11 by electrostatic adsorption (S23). For example, the control unit 2 controls a DC power supply (not shown) to apply a voltage to the electrostatic chuck 1111 and fix the substrate W to the substrate supporting unit 11 by electrostatic adsorption.

The control unit 2 controls the gas supply unit 116 to supply the heat transfer gas between the substrate W and the substrate support unit 11 from the gas supply unit 116 (S24). The control unit 2 controls the gas supply unit 116 to exhaust the heat transfer gas between the substrate W and the substrate support unit 11 through the gas supply unit 116 (S25).

The controller 2 determines whether the supply and exhaust of the heat transfer gas have been repeated a predetermined number of times (S26). The predetermined number of times is determined in advance by experiments or simulations as the number of times that the impurity 120 can be removed. If it has not been performed the predetermined number of times (S26: No), the process proceeds to S24 described above.

On the other hand, if it has been performed a predetermined number of times (S26: Yes), the control unit 2 performs the process of removing moisture (S27). For example, the control unit 2 controls the gas supply unit 20 to supply the processing gas from the gas supply unit 20 and introduce the processing gas into the plasma processing chamber 10 from the shower head 13 . Further, the control unit 2 controls the gas supply unit 116 so that the pressure of the heat transfer gas supplied from the gas supply unit 116 to between the substrate supporting unit 11 and the substrate W is made lower than when the substrate W is subjected to plasma processing. Further, the control unit 2 controls the power supply 30 so that the power of the high-frequency power supplied from the power supply 30 is set to the level lower than that for the plasma processing of the substrate W. FIG. For example, the control unit 2 controls the power supply 30 to supply an RF signal having power equal to or lower than that for the plasma processing of the substrate W and to raise the temperature of the substrate W to 200° C. or higher. Note that the control unit 2 supplies a bias RF signal from the RF power supply 31 to the substrate supporting unit 11 during the steps S24, S25 and S27. The control unit 2 may perform the processing of S27 in parallel with the processing of S24 and S25. Thereby, in the plasma processing apparatus 1, plasma is generated in the plasma processing chamber 10, and moisture is removed from the substrate W. FIG.

Thereby, the occurrence of abnormal discharge such as arcing between the substrate W and the substrate supporting portion 11 can be suppressed.

As described above, the plasma processing apparatus 1 according to the embodiment includes the plasma processing chamber 10, the substrate support section 11 (mounting table), the electrostatic chuck 1111 (fixing section), and the gas supply section 116 (heat transfer gas supply section). section, heat transfer gas exhaust section), a power supply 30 (RF power supply), and a control section 2 . Plasma processing chamber 10 is used in which plasma processing is performed. The substrate support 11 is positioned within the plasma processing chamber 10 with a substrate W and a ring assembly 112 mounted therearound. The electrostatic chuck 1111 is provided on the substrate support 11 and fixes at least one of the substrate W and the ring assembly 112 to the substrate support 11 . The gas supply section 116 supplies heat transfer gas between the substrate W support section 11 and at least one of the substrate W and the ring assembly 112 . The gas supply section 116 exhausts the heat transfer gas from between the substrate W support section 11 and at least one of the substrate W and the ring assembly 112 . Power supply 30 provides RF signals for plasma generation within plasma processing chamber 10 . When at least one of the substrate W and the ring assembly 112 is placed on the substrate support portion 11, the control portion 2 controls the pressure of the heat transfer gas supplied from the gas supply portion 116 before plasma processing is performed on the substrate W. is controlled to be lower than when the substrate W is subjected to plasma processing. Thereby, the plasma processing apparatus 1 can suppress the occurrence of abnormal electrical discharge such as arcing between the substrate W or the ring assembly 112 and the substrate supporting portion 11 .

The controller 2 performs (a) a step of supplying a heat transfer gas between the substrate support 11 and the ring assembly 112 (S12), and (b) a step of supplying a heat transfer gas between the substrate support 11 and the ring assembly 112. A step (S13) of lowering the pressure of the hot gas below (a) is performed. Thereby, the plasma processing apparatus 1 can suppress the occurrence of abnormal electrical discharge such as arcing between the ring assembly 112 and the substrate support portion 11 .

Further, the control unit 2 causes the gas supply unit 116 to supply and exhaust the heat transfer gas between the ring assembly 112 and the substrate support unit 11 at least once before performing plasma processing on the substrate W. to control. Thereby, the plasma processing apparatus 1 can remove the impurities 120 adhering to the rear surface of the ring assembly 112 and suppress the occurrence of abnormal discharge such as arcing caused by the impurities 120 .

In the steps (a) and (b) (S12 and S13), the control unit 2 supplies, from the power source 30, an RF signal with a power that is equal to or less than the time of the plasma processing of the substrate W and that the temperature of the substrate W becomes 200° C. or more. control to Thereby, the plasma processing apparatus 1 can quickly remove moisture attached to the ring assembly 112 .

In the step (S13) of (b), the control section 2 controls the pressure of the heat transfer gas supplied from the gas supply section 116 to between the substrate supporting section 11 and the ring assembly 112 to 15 Torr or less. Thereby, the plasma processing apparatus 1 can suppress the occurrence of abnormal discharge such as arcing between the ring assembly 112 and the substrate support 11 even when the RF signal is supplied into the plasma processing chamber 10 .

The control unit 2 controls the gas supply unit 116 so as to alternately supply and exhaust the heat transfer gas a plurality of times. Thereby, the plasma processing apparatus 1 can remove the impurities 120 adhering to the substrate W or the rear surface of the ring assembly 112 .

The electrostatic chuck 1111 fixes the ring assembly 112 to the substrate support 11 by electrostatic adsorption. Thereby, the plasma processing apparatus 1 can stably fix the ring assembly 112 to the substrate supporting portion 11 .

The heat transfer gas is helium gas or hydrogen gas. Thereby, the plasma processing apparatus 1 can stably transfer heat between the substrate W supporting portion 11 and the substrate W and the ring assembly 112 .

When the substrate W is placed on the substrate supporting portion 11, the control portion 2 causes the heat transfer gas to be supplied and exhausted between the substrate W and the substrate supporting portion 11 before plasma processing is performed on the substrate W. The gas supply unit 116 is controlled to perform at least once. Thereby, the plasma processing apparatus 1 can remove the impurities 120 adhering to the back surface of the substrate W, and can suppress the occurrence of abnormal discharge such as arcing caused by the impurities 120 .

The electrostatic chuck 1111 fixes the substrate W to the substrate supporter 11 by electrostatic attraction. Thereby, the plasma processing apparatus 1 can stably fix the substrate W to the substrate supporting portion 11 .

The control unit 2 performs (a) a step of introducing a processing gas into the plasma processing chamber 10 (S21), and (b) an RF power having a power lower than that during plasma processing of the substrate W into the plasma processing chamber 10 from the RF power supply. a step of supplying a signal (S22); (c) a step of electrostatically attracting the substrate W to the substrate support 11 (S23); and (d) supplying a heat transfer gas between the substrate W and the substrate support 11. and exhausting at least once (S24, S25), and (e) supplying a processing gas and an RF signal for plasma generation into the plasma processing chamber 10 (S26). Thereby, the plasma processing apparatus 1 can suppress the occurrence of abnormal electrical discharge such as arcing between the substrate W and the substrate supporting portion 11 .

The control unit 2 performs a step of supplying a bias RF signal (bias signal) from the RF power supply 31 (bias power supply) to the substrate supporting unit 11 between steps S24, S25 and S27. As a result, the plasma processing apparatus 1 generates a bias potential on the substrate W, and can attract ion components in the formed plasma to the substrate W. As shown in FIG.

Although the embodiments have been described above, the embodiments disclosed this time should be considered as examples and not restrictive in all respects. Indeed, the above-described embodiments may be embodied in many different forms. Moreover, the embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the claims.

For example, in the above embodiment, the plasma processing is performed on a semiconductor wafer as the substrate W, but the present invention is not limited to this. The substrate W may be any.

Further, in the above-described embodiment, the supply passages 115a and 115b are used to supply and exhaust the heat transfer gas in the same passage, but the present invention is not limited to this. A flow path for supplying the heat transfer gas and a flow path for discharging the heat transfer gas may be separately provided.

Further, in the above-described embodiment, the case where the substrate W and the ring assembly 112 are fixed to the substrate support portion 11 by electrostatic attraction by the electrostatic chuck 1111 has been described as an example, but the present invention is not limited to this. The substrate W and ring assembly 112 may be secured to the substrate support 11 by physical securing mechanisms such as hooks.

Further, in the above-described embodiment, the plasma processing apparatus 1 has been described as an example in which plasma etching is performed as plasma processing, but the present invention is not limited to this. The plasma processing apparatus 1 may be any apparatus that performs plasma processing on the substrate W. FIG. For example, the plasma processing apparatus 1 may be a film forming apparatus that forms a film by generating plasma.

It should be noted that the embodiments disclosed this time should be considered as examples in all respects and not restrictive. Indeed, the above-described embodiments may be embodied in many different forms. Also, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

In addition, the following additional remarks are disclosed regarding the above embodiment.

(Appendix 1)
a chamber in which plasma processing is performed;
a mounting table disposed in the chamber on which the substrate and the ring assembly are mounted around the substrate;
a fixing part provided on the mounting table for fixing at least one of the substrate and the ring assembly to the mounting table;
a heat transfer gas supply unit that supplies a heat transfer gas between the mounting table and at least one of the substrate and the ring assembly;
a heat transfer gas exhaust unit for exhausting the heat transfer gas from between the mounting table and at least one of the substrate and the ring assembly;
an RF power supply that supplies an RF (Radio Frequency) signal for plasma generation into the chamber;
When at least one of the substrate and the ring assembly is mounted on the mounting table, the pressure of the heat transfer gas supplied from the heat transfer gas supply unit is set to the pressure of the substrate before plasma processing is performed on the substrate. A control unit that controls to lower than during plasma processing for
A plasma processing apparatus having

(Appendix 2)
The control unit
(a) supplying a heat transfer gas between the mounting table and the ring assembly;
(b) lowering the pressure of the heat transfer gas supplied between the mounting table and the ring assembly below that in (a);
The plasma processing apparatus according to Supplementary Note 1, wherein

(Appendix 3)
The control unit controls the heat transfer gas supply unit and the heat transfer gas supply unit so as to supply and exhaust heat transfer gas between the ring assembly and the mounting table at least once before plasma processing is performed on the substrate. The plasma processing apparatus according to appendix 2, wherein the heat transfer gas exhaust section is controlled.

(Appendix 4)
In steps (a) and (b), the control unit controls the RF power source to supply an RF signal having a power that is equal to or lower than that for plasma processing of the substrate and that the temperature of the substrate is 200° C. or higher. The plasma processing apparatus according to appendix 2.

(Appendix 5)
The plasma processing according to appendix 2, wherein in the step (b), the control unit controls the pressure of the heat transfer gas supplied from the heat transfer gas supply unit to between the mounting table and the ring assembly to 15 Torr or less. Device.

(Appendix 6)
The plasma processing apparatus according to appendix 3, wherein the control unit controls the heat transfer gas supply unit so as to alternately supply and exhaust the heat transfer gas a plurality of times.

(Appendix 7)
The plasma processing apparatus according to any one of appendices 1 to 6, wherein the fixing section fixes the ring assembly to the mounting table by electrostatic attraction.

(Appendix 8)
The plasma processing apparatus according to any one of appendices 1 to 7, wherein the heat transfer gas is helium gas or hydrogen gas.

(Appendix 9)
When the substrate is mounted on the mounting table, the control unit performs at least one supply and exhaust of a heat transfer gas between the substrate and the mounting table before plasma processing is performed on the substrate. The plasma processing apparatus according to appendix 1, wherein the heat transfer gas supply unit and the heat transfer gas exhaust unit are controlled so as to rotate.

(Appendix 10)
The plasma processing apparatus according to appendix 9, wherein the control unit controls the heat transfer gas supply unit and the heat transfer gas exhaust unit so as to alternately supply and exhaust the heat transfer gas a plurality of times.

(Appendix 11)
11. The plasma processing apparatus according to any one of appendices 1 to 10, wherein the fixing unit fixes the substrate to the mounting table by electrostatic adsorption.

(Appendix 12)
The control unit
(a) introducing a process gas into the chamber;
(b) supplying an RF signal from the RF power source into the chamber at a power lower than that during plasma processing of the substrate;
(c) electrostatically attracting the substrate to the mounting table;
(d) supplying and exhausting a heat transfer gas between the substrate and the mounting table at least once;
(e) supplying a processing gas and the RF signal for plasma generation into the chamber.

(Appendix 13)
further comprising a bias power supply;
The control unit performs a step of supplying a bias signal from the bias power source to the mounting table between steps (d) and (e).
13. The plasma processing apparatus according to appendix 12.

(Appendix 14)
placing at least one of the substrate and the ring assembly mounted around the substrate on a mounting table arranged in a chamber in which plasma processing is performed;
a step of lowering the pressure of the heat transfer gas supplied between the mounting table and at least one of the substrate and the ring assembly before performing the plasma processing on the substrate, compared with that during the plasma processing on the substrate; ,
Abnormal discharge suppression method having.

(Appendix 15)
a chamber in which plasma processing is performed;
a mounting table disposed in the chamber on which the substrate and the ring-shaped ring assembly are mounted around the substrate;
a fixing part that is provided on the mounting table and fixes at least one of the substrate and the ring assembly;
a supply unit that supplies a heat transfer gas between the mounting table and at least one of the substrate and the ring assembly;
a power supply that supplies high-frequency power for generating plasma in the chamber;
When at least one of the substrate and the ring assembly is replaced, before performing plasma processing on the substrate, the pressure of the heat transfer gas supplied from the supply unit is made lower than that during plasma processing on the substrate. a control unit that controls
A plasma processing apparatus having

(Appendix 16)
The supply unit supplies a heat transfer gas between the mounting table and the ring assembly,
When the ring assembly is replaced, the control unit adjusts the pressure of the heat transfer gas supplied from the supply unit between the mounting table and the ring assembly during seasoning in the chamber so as to perform plasma processing on the substrate. 16. The plasma processing apparatus according to appendix 15, wherein the power of the high-frequency power supplied from the power supply unit is controlled to be lower than the time of the plasma processing on the substrate.

(Appendix 17)
When the substrate or the ring assembly is replaced, the control unit causes a heat transfer gas to flow between the replaced substrate or the ring assembly and the mounting table before plasma processing is performed on the substrate. 18. The plasma processing apparatus according to appendix 16 or 17, wherein the supply unit is controlled to perform supply and exhaust at least once.

(Appendix 18)
16. According to appendix 16, during the seasoning, the control unit controls the power supply unit to supply high-frequency power with a power that is equal to or lower than that for plasma processing of the substrate and that causes the temperature of the substrate to be 200° C. or higher. Plasma processing equipment.

(Appendix 19)
19. The control unit according to any one of appendices 16 to 18, wherein during the seasoning, the pressure of the heat transfer gas supplied from the supply unit to between the mounting table and the ring assembly is controlled to 15 Torr or less. plasma processing equipment.

(Appendix 20)
18. The plasma processing apparatus according to appendix 17, wherein the control unit controls the supply unit to alternately supply and exhaust the heat transfer gas a plurality of times.

(Appendix 21)
21. The plasma processing apparatus according to any one of appendices 15 to 20, wherein the fixing section fixes at least one of the substrate and the ring assembly to the mounting table by electrostatic adsorption.

(Appendix 22)
The power supply unit can supply high-frequency power to the mounting table,
22. The plasma processing apparatus according to Supplementary note 21, wherein the control unit performs control such that, when the fixing unit electrostatically attracts, high-frequency power for attraction is applied from the power supply unit to the mounting table.

(Appendix 23)
The plasma processing apparatus according to any one of appendices 15 to 22, wherein the heat transfer gas is helium gas or hydrogen gas.

(Appendix 24)
exchanging at least one of a substrate mounted on a mounting table arranged in a chamber in which plasma processing is performed and a ring-shaped ring assembly mounted around the substrate;
When at least one of the substrate and the ring assembly is replaced, before plasma processing is performed on the substrate, a heat transfer gas supplied between the mounting table and at least one of the substrate and the ring assembly is reduced. lowering the pressure below that during plasma treatment of the substrate;
Abnormal discharge suppression method having.

1 plasma processing apparatus 2 control unit 10 plasma processing chamber 11 substrate support unit 30 power source 112 ring assembly 116 gas supply unit 1111 electrostatic chuck W substrate

Claims (14)

a chamber in which plasma processing is performed;
a mounting table disposed in the chamber on which the substrate and the ring assembly are mounted around the substrate;
a fixing part provided on the mounting table for fixing at least one of the substrate and the ring assembly to the mounting table;
a heat transfer gas supply unit that supplies a heat transfer gas between the mounting table and at least one of the substrate and the ring assembly;
a heat transfer gas exhaust unit for exhausting the heat transfer gas from between the mounting table and at least one of the substrate and the ring assembly;
an RF power supply that supplies an RF (Radio Frequency) signal for plasma generation into the chamber;
When at least one of the substrate and the ring assembly is mounted on the mounting table, the pressure of the heat transfer gas supplied from the heat transfer gas supply unit is set to the pressure of the substrate before plasma processing is performed on the substrate. A control unit that controls to lower than during plasma processing for
A plasma processing apparatus having The control unit
(a) supplying a heat transfer gas between the mounting table and the ring assembly;
(b) lowering the pressure of the heat transfer gas supplied between the mounting table and the ring assembly below that in (a);
The plasma processing apparatus according to claim 1, wherein The control unit controls the heat transfer gas supply unit and the heat transfer gas supply unit so as to supply and exhaust heat transfer gas between the ring assembly and the mounting table at least once before plasma processing is performed on the substrate. The plasma processing apparatus according to claim 2, wherein said heat transfer gas exhaust section is controlled. In steps (a) and (b), the control unit controls the RF power source to supply an RF signal having a power that is equal to or lower than that for plasma processing of the substrate and that the temperature of the substrate is 200° C. or higher. The plasma processing apparatus according to claim 2. 3. The plasma according to claim 2, wherein in the step (b), the control section controls the pressure of the heat transfer gas supplied from the heat transfer gas supply section to between the mounting table and the ring assembly to 15 Torr or less. processing equipment. 4. The plasma processing apparatus according to claim 3, wherein the control unit controls the heat transfer gas supply unit so as to alternately supply and exhaust the heat transfer gas a plurality of times. 3. The plasma processing apparatus according to claim 2, wherein the fixing section fixes the ring assembly to the mounting table by electrostatic adsorption. The plasma processing apparatus according to claim 1, wherein the heat transfer gas is helium gas or hydrogen gas. When the substrate is mounted on the mounting table, the control unit performs at least one supply and exhaust of a heat transfer gas between the substrate and the mounting table before plasma processing is performed on the substrate. 2. The plasma processing apparatus according to claim 1, wherein said heat transfer gas supply unit and said heat transfer gas exhaust unit are controlled so as to rotate. 10. The plasma processing apparatus according to claim 9, wherein the control unit controls the heat transfer gas supply unit and the heat transfer gas exhaust unit so as to alternately supply and exhaust the heat transfer gas a plurality of times. The plasma processing apparatus according to claim 9, wherein the fixing section fixes the substrate to the mounting table by electrostatic adsorption. The control unit
(a) introducing a process gas into the chamber;
(b) supplying an RF signal from the RF power source into the chamber at a power lower than that during plasma processing of the substrate;
(c) electrostatically attracting the substrate to the mounting table;
(d) supplying and exhausting a heat transfer gas between the substrate and the mounting table at least once;
12. The plasma processing apparatus of claim 11, further comprising: (e) supplying a process gas and an RF signal for generating the plasma into the chamber. further comprising a bias power supply;
The control unit performs a step of supplying a bias signal from the bias power source to the mounting table between steps (d) and (e).
The plasma processing apparatus according to claim 12. placing at least one of the substrate and the ring assembly mounted around the substrate on a mounting table arranged in a chamber in which plasma processing is performed;
a step of lowering the pressure of the heat transfer gas supplied between the mounting table and at least one of the substrate and the ring assembly before performing the plasma processing on the substrate, compared with that during the plasma processing on the substrate; ,
Abnormal discharge suppression method having.

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