Method for determining the amount of wear on an edge ring, plasma processing apparatus, and substrate processing system

Abstract

Disclosed is a method comprising a step (a) for generating plasma in a chamber of a plasma processing device. The plasma processing device comprises a substrate support unit provided in the chamber. The substrate support unit includes a first region for supporting the substrate, and a second region for supporting an edge ring. The first region includes a first electrode, and the second region includes a second electrode. The method further comprises a step (b) for applying a voltage pulse to each of the first electrode and the second electrode periodically so as to draw an ion from the plasma to the substrate support unit. The method further comprises a step (c) for determining the amount of wear of the edge ring on the basis of a first voltage value of the first electrode and a second voltage value of the second electrode when the voltage pulse is being applied to each of the first electrode and the second electrode.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a method for determining a consumption amount of an edge ring, a plasma processing apparatus, and a substrate processing system.

Background Art

[0002] A plasma processing apparatus is used for performing plasma processing on a substrate. The plasma processing apparatus includes a substrate support in a chamber. The substrate support supports a substrate placed thereon. The substrate support may further support an edge ring. The substrate is arranged on the substrate support and within a region surrounded by the edge ring. As described in Patent Document 1 below, the plasma processing apparatus may be configured to apply a voltage to the edge ring.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of Invention

Problem to be Solved by Invention

[0004] The present disclosure provides a technique for determining the consumption amount of an edge ring.

Means for Solving Problem

[0005] In one exemplary embodiment, a method for determining the wear of an edge ring is provided. The method includes (a) generating plasma in a chamber of a plasma processing apparatus. The plasma processing apparatus includes a substrate support provided in the chamber. The substrate support includes a first region for supporting a substrate placed thereon and a second region for supporting an edge ring placed thereon. The first region includes a first electrode, and the second region includes a second electrode. The method further includes (b) periodically applying pulses of voltage to the first electrode and the second electrode, respectively, in order to draw ions from the plasma to the substrate support while the plasma is being generated in step (a). The method further includes (c) determining the wear of the edge ring based on a first voltage value of the first electrode and a second voltage value of the second electrode when pulses are applied to the first electrode and the second electrode, respectively, in step (b). [Effects of the Invention]

[0006] According to one exemplary embodiment, a technique for determining the wear amount of an edge ring is provided. [Brief explanation of the drawing]

[0007] [Figure 1] This is a flowchart illustrating a method for determining the wear amount of an edge ring according to one exemplary embodiment. [Figure 2] This is a diagram illustrating an example configuration of a plasma processing system. [Figure 3] This is a diagram illustrating an example configuration of a capacitively coupled plasma processing apparatus. [Figure 4] This figure shows an example of a voltage pulse. [Figure 5] This figure shows one embodiment of step STc of the method shown in Figure 1. [Figure 6] This figure shows an example of the relationship between the ratio of the time change of the second voltage value to the time change of the first voltage value and the wear rate of the edge ring. [Figure 7] This is a flowchart illustrating a method for determining the wear amount of an edge ring according to another exemplary embodiment. [Figure 8]This figure shows an example of the relationship between the ratio of the second voltage value to the first voltage value and the thickness of the edge ring. [Figure 9] This figure shows a substrate processing system according to one exemplary embodiment. [Modes for carrying out the invention]

[0008] Various exemplary embodiments will be described in detail below with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals.

[0009] Figure 1 is a flowchart of a method for determining the wear amount of an edge ring according to one exemplary embodiment. The method MT shown in Figure 1 is performed to determine the wear amount of an edge ring in a plasma processing apparatus.

[0010] Figure 2 is a diagram illustrating an example configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support unit 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space, and at least one gas outlet for discharging gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20, which will be described later, and the gas outlet is connected to an exhaust system 40, which will be described later. The substrate support unit 11 is located in the plasma processing space and has a substrate support surface for supporting a substrate.

[0011] The plasma generation unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR), a helicon wave-excited plasma (HWP), or a surface wave plasma (SWP), etc.

[0012] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described herein. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform 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 implemented, for example, by a computer 2a. The processing unit 2a1 may be configured to perform various control operations by reading a program from the storage unit 2a2 and executing the read program. This program may be stored in the storage unit 2a2 in advance, or it may be obtained via a medium when needed. The obtained program is stored in the storage unit 2a2 and 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 it may be a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The memory 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 device 1 via a communication line such as a LAN (Local Area Network).

[0013] The following describes an example configuration of a capacitively coupled plasma processing apparatus as an example of plasma processing apparatus 1. Figure 3 is a diagram illustrating an example configuration of a capacitively coupled plasma processing apparatus.

[0014] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is located inside the plasma processing chamber 10. The shower head 13 is located above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the side walls 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 is grounded. The shower head 13 and the substrate support unit 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0015] The substrate support portion 11 includes a main body portion 111 and an edge ring 112. The main body portion 111 has a first region 111a (central region) for supporting the substrate W and a second region 111b (annular region) for supporting the edge ring 112. A wafer is an example of a substrate W. The second region 111b of the main body portion 111 surrounds the first region 111a of the main body portion 111 in a plan view. The substrate W is placed on the first region 111a of the main body portion 111, and the edge ring 112 is placed on the second region 111b of the main body portion 111 so as to surround the substrate W on the first region 111a of the main body portion 111.

[0016] In one embodiment, the main body portion 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. 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 forms a first region 111a. In one embodiment, the ceramic member 1111a further forms a second region 111b. Note that other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may also form the second region 111b. In this case, the edge ring 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.

[0017] The edge ring 112 includes one or more annular members. The edge ring 112 is formed of a conductive material or an insulating material.

[0018] In addition, the substrate support portion 11 may include a temperature control module configured to adjust the temperature of at least one of the electrostatic chuck 1111, the edge ring 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. In addition, the substrate support portion 11 may include a heat transfer gas supply unit configured to supply heat transfer gas to the gap between the back surface of the substrate W and the first region 111a.

[0019] The showerhead 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas inlet 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 the plurality of gas inlet ports 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

[0020] 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 processing gas to the shower head 13 from a corresponding gas source 21 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include at least one flow modulation device that modulates or pulses the flow rate of at least one processing gas.

[0021] The exhaust system 40 may be connected to, for example, a gas outlet 10e located 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 regulating valve regulates the pressure in the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0022] The first region 111a described above includes a first electrode 121. The first electrode 121 may be located within the ceramic member 1111a of the electrostatic chuck 1111. The first electrode 121 may be a film formed from a conductive material. The planar shape of the first electrode 121 may be circular. The second region 111b includes a second electrode 122. The second electrode 122 may be located within the ceramic member 1111a of the electrostatic chuck 1111. The second electrode 122 may be a film formed from a conductive material. The planar shape of the second electrode 122 may be substantially annular.

[0023] The plasma processing apparatus 1 further comprises a high-frequency power supply 31. The high-frequency power supply 31 constitutes a plasma generation unit 12 in one embodiment. The high-frequency power supply 31 is configured to generate source high-frequency power RF. The source high-frequency power RF has a source frequency f RF It includes. Source frequency f RF The frequency can be in the range of 10 MHz to 150 MHz. The high-frequency power supply 31 is electrically connected to the high-frequency electrode via a matching unit 33 and is configured to supply source high-frequency power RF to the high-frequency electrode. The high-frequency electrode may be a conductive member of the base 1110, at least one electrode provided in the ceramic member 1111a, or an upper electrode. When source high-frequency power RF is supplied to the high-frequency electrode, plasma is generated from the gas in the chamber 10.

[0024] The matching circuit 33 has a variable impedance. The variable impedance of the matching circuit 33 is set to reduce reflection of the source high-frequency power RF from the load. The matching circuit 33 can be controlled, for example, by the control unit 2.

[0025] The plasma processing apparatus 1 further comprises a pulse generator 43. The pulse generator 43 is configured to periodically apply pulses of voltage having a waveform period to each of the first electrode 121 and the second electrode 122. The frequency, which is the reciprocal of the time length of the waveform period, may be a frequency in the range of 100 kHz to 60 MHz. The voltage pulse may be a negative voltage pulse or a negative DC voltage pulse. Figure 4 shows an example of a voltage pulse. As shown in Figure 4, the voltage pulse may be a rectangular pulse. The voltage pulse may have any waveform, such as a triangular pulse.

[0026] In one embodiment, the plasma processing apparatus 1 may further include a DC power supply 41, smoothing circuits 421 and 422, damping circuits 441 and 442, and filters 451 and 452. The pulse generator 43 may also include switching circuits 431 and 432. Each of the switching circuits 431 and 432 has a switching element. The opening and closing of the switching element can be controlled by the control unit 2.

[0027] The DC power supply 41 has two outputs. One output of the DC power supply 41 is connected to the first electrode 121 via a smoothing circuit 421, a switching circuit 431, a damping circuit 441, and a filter 451. The switching circuit 431 generates a voltage pulse from the DC voltage from one output of the DC power supply 41 by opening and closing, and applies this voltage pulse to the first electrode 121. A portion of the voltage pulse from the switching circuit 431 may be branched and applied to the second electrode 122. The filter 451 is a filter that blocks or reduces high-frequency power.

[0028] The other output of the DC power supply 42 is connected to the second electrode 122 via a smoothing circuit 422, a switching circuit 432, a damping circuit 442, and a filter 452. The switching circuit 432 generates a voltage pulse from the DC voltage from the other output of the DC power supply 41 by opening and closing, and applies this voltage pulse to the second electrode 122. The filter 452 is a filter that blocks or reduces high-frequency power.

[0029] As shown in Figure 3, the plasma processing apparatus 1 further includes a sensor 46. The sensor 46 is configured to measure a first voltage value V1 of the first electrode 121 and a second voltage value V2 of the second electrode 122.

[0030] The following will describe Method MT in detail, again referring to Figure 1. In the following description, we will take the case where Method MT is applied to Plasma Processing Apparatus 1 as an example. However, Method MT may also be applied to a plasma processing apparatus other than Plasma Processing Apparatus 1.

[0031] As shown in Figure 1, method MT includes steps STa to STc. In one embodiment, steps STa and STb are performed to perform plasma processing on a substrate W in a chamber 10. Multiple substrates W may be processed sequentially in steps STa and STb. That is, multiple substrates W are sequentially housed in the chamber 10 and processed using plasma in steps STa and STb. Alternatively, multiple substrates W may be sequentially loaded into the chamber 10 of the process module, which is the plasma processing apparatus 1, in a substrate processing system PS described later, and processed thereafter.

[0032] In step STa, plasma is generated in the chamber 10. In step STa, the control unit 2 controls the gas supply unit 20 to supply gas into the chamber 10. In step STa, the control unit 2 controls the exhaust system 40 to set the pressure in the chamber 10 to a specified pressure. In step STa, the control unit 2 controls the plasma generation unit 12 to generate plasma from the gas in the chamber 10. In one embodiment, the control unit 2 controls the high-frequency power supply 31 to supply source high-frequency power RF to the high-frequency electrode.

[0033] Process STb is performed while plasma is being generated in process STa. In process STb, voltage pulses are periodically applied to the first electrode 121 and the second electrode 122 in order to draw ions from the plasma into the substrate support 11. In process STb, the control unit 2 controls the pulse generator 43 to periodically apply voltage pulses to the first electrode 121 and the second electrode 122.

[0034] In process STc, the wear amount of the edge ring 112 is determined. The wear amount of the edge ring 112 is determined based on the first voltage value V1 and the second voltage value V2 acquired by the sensor 46 when the pulses are applied to the first electrode 121 and the second electrode 122, respectively, in process STb.

[0035] Figure 5 shows one embodiment of step STc of the method shown in Figure 1. In one embodiment, step STc includes steps STc1 to STc3, as shown in Figure 5. In step STc1, the ratio (dV2 / dV1) of the time change dV2 of the second voltage value V2 to the time change dV1 of the first voltage value V1 is determined. The ratio (dV2 / dV1) can be determined by the control unit 2. The time change dV1 is determined from the time series of the first voltage value V1 acquired while step STb is being executed. The time change dV2 is determined from the time series of the second voltage value V2 acquired while step STb is being executed.

[0036] In process STc2, the wear rate of the edge ring 112 corresponding to the ratio value (dV2 / dV1) is determined using a predetermined relationship between the magnitude of the ratio value (dV2 / dV1) and the wear rate of the edge ring 112. The wear rate of the edge ring 112 is the rate at which the thickness of the edge ring 112 decreases, and can be determined by the control unit 2. Figure 6 shows an example of the relationship between the ratio of the time change of the second voltage value to the time change of the first voltage value and the wear rate of the edge ring. As shown in Figure 6, there is a correlation between the ratio value (dV2 / dV1) and the wear rate of the edge ring 112. The control unit 2 has a function that represents the correlation between the ratio value (dV2 / dV1) and the wear rate of the edge ring 112. The control unit 2 can use this function to determine the wear rate of the edge ring 112 corresponding to the ratio value (dV2 / dV1).

[0037] In process STc3, the product of the wear rate of the edge ring 112 and the length of time the edge ring 112 is exposed to the plasma is determined as the amount of wear of the edge ring 112, i.e., the decrease in the thickness of the edge ring 112. The amount of wear of the edge ring 112 can be determined by the control unit 2.

[0038] In the plasma processing apparatus 1, the impedance of the substrate W does not substantially change over time, but the impedance of the edge ring 112 changes over time as the edge ring 112 wears down. Therefore, the second voltage value V2 changes over time with respect to the first voltage value V1. Consequently, the relative relationship between the first voltage value V1 and the second voltage value V2 reflects the amount of wear on the edge ring 112. Thus, according to method MT, it is possible to determine the amount of wear on the edge ring 112 based on the first voltage value V1 and the second voltage value V2.

[0039] The following describes a method for determining the wear amount of the edge ring according to another exemplary embodiment, with reference to Figure 7. Figure 7 is a flowchart of a method for determining the wear amount of the edge ring according to another exemplary embodiment. In the following description, we will take the case where the method MTB shown in Figure 7 is applied to the plasma processing apparatus 1 as an example. However, the method MTB may be applied to a plasma processing apparatus other than the plasma processing apparatus 1.

[0040] Method MTB, like Method MT, includes steps STa to STc. Method MTB may further include steps STp and STd. Steps STa to STc may be performed immediately after step STd.

[0041] In step STp, plasma treatment is performed on the substrate W within the chamber 10. In step STp, the plasma treatment may be applied sequentially to multiple substrates W. That is, multiple substrates W are sequentially housed in the chamber 10 and treated with plasma in steps STa and STb. Alternatively, the multiple substrates W may be sequentially loaded into the chamber 10 of the process module, which is the plasma processing apparatus 1, in the substrate processing system PS described later, and then processed.

[0042] In step STp, the control unit 2 controls the gas supply unit 20 to supply gas into the chamber 10. In step STp, the control unit 2 controls the exhaust system 40 to set the pressure in the chamber 10 to a specified pressure. In step STp, the control unit 2 controls the plasma generation unit 12 to generate plasma from the gas in the chamber 10. In one embodiment, the control unit 2 controls the high-frequency power supply 31 to supply source high-frequency power RF to the high-frequency electrodes. In step STp, the control unit 2 may control the pulse generator 43 to periodically apply voltage pulses to the first electrode 121 and the second electrode 122, respectively, in order to draw ions from the plasma into the substrate support unit 11.

[0043] In the subsequent step STd, the chamber 10 is dry-cleaned. In step STd, the control unit 2 controls the gas supply unit 20 to supply cleaning gas into the chamber 10. In step STd, the control unit 2 controls the exhaust system 40 to set the pressure inside the chamber 10 to a specified pressure. In step STd, the control unit 2 controls the plasma generation unit 12 to generate plasma from the cleaning gas inside the chamber 10. In one embodiment, the control unit 2 controls the high-frequency power supply 31 to supply source high-frequency power RF to the high-frequency electrode.

[0044] Steps STa and STb of Method MTB are performed to measure a first voltage value V1 and a second voltage value V2, which will be used in step STc11 described later. Steps STa and STb may be performed with the substrate W housed in the chamber 10.

[0045] Step STc of Method MTB includes steps STc11 to STc13. In step STc11, the ratio (V2 / V1) of the second voltage value V2 to the first voltage value V1 is determined. The first voltage value V1 and the second voltage value V2 are measured by the sensor 46 when voltage pulses are applied to the first electrode 121 and the second electrode 122, respectively, in step STb. The ratio (V2 / V1) can be determined by the control unit 2.

[0046] In step STc12, the thickness of the edge ring 112 corresponding to the ratio value (V2 / V1) is determined using a predetermined relationship between the magnitude of the ratio value (V2 / V1) and the thickness of the edge ring 112. The thickness of the edge ring 112 can be determined by the control unit 2. Figure 8 shows an example of the relationship between the ratio value of the second voltage value to the first voltage value and the thickness of the edge ring. As shown in Figure 8, there is a correlation between the ratio value (V2 / V1) and the thickness of the edge ring 112. The control unit 2 has a function of the correlation between the ratio value (V2 / V1) and the thickness of the edge ring 112. The control unit 2 can use this function to determine the thickness of the edge ring 112 corresponding to the ratio value (V2 / V1).

[0047] In step STc13, the wear amount of the edge ring 112 is determined. The wear amount of the edge ring 112 can be determined by the control unit 2. The wear amount of the edge ring 112 is determined by subtracting the thickness of the edge ring 112, which was determined in step STc12, from the initial value of the thickness of the edge ring 112.

[0048] As explained above, in the MTB method, it is possible to determine the wear amount of the edge ring 112 based on the first voltage value V1 and the second voltage value V2. Furthermore, the material deposited on the edge ring 112 in step STp is removed in step STd. Therefore, it is possible to measure the second voltage value V2 in step STp without being affected by the material deposited on the edge ring 112.

[0049] The following describes several steps that may be added to Method MT and Method MTB (hereinafter, Method MT and Method MTB may each be referred to as "Method M").

[0050] (Voltage application process)

[0051] In one embodiment, method M may further include a voltage application step. The voltage application step includes applying a voltage from a power supply to the edge ring 112 in order to correct the thickness of the sheath (plasma sheath) on the edge ring 112 when the amount of wear of the edge ring 112 obtained in step STc is greater than a first threshold. This power supply may be a DC power supply connected to the edge ring 112 and is controlled by the control unit 2 in the voltage application step. The voltage application step is performed when the substrate W is placed on the substrate support 11 and plasma is being generated in the chamber 10. The voltage application step may also be performed when plasma is being generated in step STa.

[0052] The position of the upper end of the sheath (plasma sheath) on the edge ring 112 decreases in proportion to the wear of the edge ring 112. The voltage level of the voltage applied to the edge ring 112 during the voltage application process is predetermined to a level corresponding to the wear of the edge ring 112, so as to reduce or eliminate the difference between the position of the upper end of the sheath on the edge ring 112 and the position of the upper end of the sheath on the substrate W.

[0053] (Parameter change process)

[0054] In one embodiment, method M may further include a parameter changing step. The parameter changing step includes changing at least one parameter if the amount of wear of the edge ring 112 obtained in step STc is greater than a first threshold. The voltage application step is performed when plasma is generated in the chamber 10 with the substrate W placed on the substrate support 11. The parameter changing step may be performed when plasma is generated in step STa.

[0055] The parameter to be changed in the parameter change process includes at least one of the following parameters: the power level of the source high-frequency power RF, the voltage level of the DC voltage pulse applied to the first electrode 121, the voltage level of the DC voltage pulse applied to the second electrode 122, the flow rate of the gas supplied from the gas supply unit 20 into the chamber 10, the pressure inside the chamber 10, the pressure of the heat transfer gas supplied from the heat transfer gas supply unit into the gap between the substrate support unit 11 and the back surface of the substrate W, and the in-plane temperature distribution at the substrate support unit 11. In the parameter change process, at least one of the high-frequency power supply 31, the gas supply unit 20, the exhaust system 40, the heat transfer gas supply unit, and the temperature control module is controlled by the control unit 2.

[0056] (Notification process)

[0057] In one embodiment, method M may further include a notification step. In the notification step, if the amount of wear of the edge ring 112 obtained in step STc is greater than a second threshold, the control unit 2 provides a notification indicating the timing for replacing the edge ring 112. This notification may be emitted as sound from a speaker by the control unit 2, or, in addition to the above, may be displayed on a display by the control unit 2. The second threshold is greater than the first threshold described above.

[0058] (Cleaning process)

[0059] In one embodiment, method M may further include a cleaning step. The cleaning step includes cleaning the chamber 10 while the feeding of substrates into the chamber 10 is stopped when the amount of wear of the edge ring 112 obtained in step STc is greater than the second threshold described above. In the cleaning step, the gas supply unit 20 is controlled by the control unit 2 to supply cleaning gas into the chamber 10. The cleaning step can be performed with a dummy substrate placed on the first region 111a or with no object placed on the first region 111a. The cleaning of the chamber 10 performed in the cleaning step may be the same as the dry cleaning in step STd.

[0060] (Edge ring replacement process)

[0061] In one embodiment, method M may further include an edge ring replacement step. Method M, including the edge ring replacement step, is performed in a substrate processing system PS.

[0062] Figure 9 shows a substrate processing system according to one exemplary embodiment. The substrate processing system PS shown in Figure 9 comprises a transport module TM (vacuum transport module), a plurality of process modules PM1 to PM7, and a control unit MC. The substrate processing system PS may further comprise tables Ta to Td, containers Fa to Fd, a loader module LM, an aligner AN, a load lock module LL1, a load lock module LL2, and a stocker module RSM. The number of tables, containers, and load lock modules in the substrate processing system PS can be one or any number. Also, the number of process modules in the substrate processing system PS can be two or any number.

[0063] The bases Ta to Td are arranged along one edge of the loader module LM. The containers Fa to Fd are each mounted on bases Ta to Td. Each of the containers Fa to Fd is, for example, a container called a FOUP (Front Opening Unified Pod). Each of the containers Fa to Fd is configured to house the substrate W inside.

[0064] The loader module LM has a transport chamber. The pressure inside the transport chamber of the loader module LM is set to atmospheric pressure. The loader module LM has a transport robot LR. The transport robot LR is controlled by the control unit MC. The transport robot LR is configured to transport the substrate W through the transport chamber of the loader module LM. The transport robot LR can transport the substrate W between each of the containers Fa to Fd 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 Fa to Fd. The aligner AN is connected to the loader module LM. The aligner AN is configured to adjust (align) the position of the substrate W.

[0065] Each of the load lock modules LL1 and LL2 is connected between the transport chamber TC of the loader module LM and the transport chamber TC of the transport module TM. Each of the load lock modules LL1 and LL2 provides a pre-pressure chamber. A gate valve is provided between the pre-pressure chamber of each of the load lock modules LL1 and LL2 and the transport chamber of the loader module LM. A gate valve is also provided between the pre-pressure chamber of each of the load lock modules LL1 and LL2 and the transport chamber TC of the transport module TM.

[0066] The transport module TM includes a transport chamber TC and a transport robot TR. The transport chamber TC is configured to allow for depressurization of the space inside it. The transport robot TR includes picks TP. The transport robot TR may include at least two picks TP. In the illustrated example, the transport robot TR includes two picks TP. One of the two picks TP is positioned above the other. The transport robot TR is configured to transport a substrate W placed on any one of the two picks TP through the transport chamber TC. The transport robot TR is controlled by a control unit MC.

[0067] The transport module TM may be provided with position detection sensors S11 and S12. Position detection sensors S11 and S12 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM1. Position detection sensors S11 and S12 are used to correct the position of the substrate W and edge ring being transported from the transport module TM to the process module PM1. Position detection sensors S11 and S12 are provided, for example, near a gate valve that separates the transport module TM and the process module PM1. Position detection sensors S11 and S12 are arranged, for example, such that the distance between them is smaller than the outer diameter of the substrate W and smaller than the inner diameter of the edge ring. The transport module TM may also be provided with position detection sensors S21, S22, S31, S32, S41, S42, S51, S52, S61, S62, S71, S72, similar to position detection sensors S11 and S12. Position detection sensors S21 and S22 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM2. Position detection sensors S31 and S32 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM3. Position detection sensors S41 and S42 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM4. Position detection sensors S51 and S52 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM5. Position detection sensors S61 and S62 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM6. Position detection sensors S71 and S72 are provided on the transport path of the substrate W and edge ring from the transport module TM to the process module PM7.

[0068] In one embodiment, the transport robot TR is configured to transport an edge ring for the substrate support of any one of the process modules PM1 to PM7. The edge ring is placed on any one of two picks TP and transported. If the edge ring is used within the process module, it may be transported using the lower of the two picks TP. If the edge ring is a replacement part to be replaced with a used one, it may be transported using the upper of the two picks TP.

[0069] Each pick TP has a sensor TS. The sensor TS is an optical sensor and is configured to measure the position of the edge ring on the substrate support.

[0070] Each of the process modules PM1 to PM7 is a device configured to perform dedicated substrate processing and has a processing chamber. A gate valve is provided between the processing chamber and the transport chamber TC. At least one of the process modules PM1 to PM7 is a plasma processing device 1.

[0071] The stocker module RSM is connected to the transport chamber TC via a gate valve. The stocker module RSM includes a chamber. The chamber of the stocker module RSM is configured to allow for depressurization of its internal space. The chamber of the stocker module RSM provides a first space and a second space. The first space may be located below the second space. A cassette is housed within the first space. The cassette is configured to house (or store) an edge ring within it.

[0072] The second space houses an aligner. The aligner includes a rotating stage and optical sensors. The aligner is configured to detect and adjust the position of the edge rings on the rotating stage using the rotating stage and optical sensors.

[0073] The control unit MC is configured to control each part of the substrate processing system PS. The control unit MC may be a computer equipped with a processor, memory, input device, display device, etc. The control unit MC executes a control program stored in the memory and controls each part of the substrate processing system PS based on the recipe data stored in the memory. The control unit MC may also be control unit 2. The control unit MC may be a separate control unit from control unit 2, or it may be configured together with control unit 2 as a control unit that controls each part of the substrate processing system PS.

[0074] The edge ring replacement process is performed when the amount of wear on the edge ring 112 obtained in process STc is greater than the second threshold described above. The edge ring replacement process is performed when the loading of substrates into the chamber 10 is stopped. In the edge ring replacement process, the control unit MC removes the edge ring 112 from the chamber 10 using the transport robot TR, while maintaining a reduced pressure in the space inside the chamber 10 (plasma processing space) in order to replace the edge ring 112 inside the chamber 10. In the edge ring replacement process, the transport module TM and its transport robot TR are controlled by the control unit MC.

[0075] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments.

[0076] For example, the plasma processing apparatus 1 may be equipped with two DC power supplies instead of the DC power supply 41 having two outputs.

[0077] Herein, various exemplary embodiments included in this disclosure are described in [E1] to [E20] below.

[0078] [E1] A method for determining the wear amount of the edge ring, (a) A step of generating plasma in a chamber of a plasma processing apparatus, the plasma processing apparatus including a substrate support portion provided in the chamber, the substrate support portion including a first region for supporting a substrate placed thereon and a second region for supporting the edge ring placed thereon, the first region including a first electrode, and the second region including a second electrode, (b) While the plasma is being generated in (a), a step of periodically applying a DC voltage pulse to the first electrode and the second electrode in order to draw ions from the plasma to the substrate support, (c) A step of determining the amount of wear of the edge ring based on the first voltage value of the first electrode and the second voltage value of the second electrode when the pulses are applied to the first electrode and the second electrode, respectively, in (b) above, A method that includes this.

[0079] Although the impedance of the substrate does not substantially change over time, the impedance of the edge ring changes over time as the edge ring wears down. Therefore, the second voltage value changes over time relative to the first voltage value. Consequently, the relative relationship between the first voltage value and the second voltage value reflects the amount of wear on the edge ring. Thus, according to the above embodiment, it is possible to determine the amount of wear on the edge ring based on the first voltage value of the first electrode and the second voltage value of the second electrode.

[0080] [E2] The above (c) is, The ratio of the time change of the second voltage value to the time change of the first voltage value is determined, Using a predetermined relationship between the magnitude of the ratio and the wear rate of the edge ring, the wear rate of the edge ring corresponding to the determined ratio is determined, The amount of wear on the edge ring is determined by calculating the product of the determined wear rate of the edge ring and the length of time the edge ring is exposed to the plasma, The method described in E1, including the method described in E1.

[0081] [E3] The above (c) is, To determine the ratio of the second voltage value to the first voltage value, Using a predetermined relationship between the magnitude of the ratio and the thickness of the edge ring, the thickness of the edge ring corresponding to the determined ratio is determined. The method described in E1, including the method described in E1.

[0082] [E4] A step of processing a substrate placed on the substrate support portion with plasma generated from a processing gas in the chamber, After the above-mentioned process of processing the substrate, a step of dry cleaning the chamber is performed, It further includes, The above (a), (b), and (c) are performed immediately after the dry cleaning process. Methods used in E3.

[0083] [E5] The method according to any one of E1 to E4, wherein the DC voltage pulse is a negative DC voltage pulse.

[0084] [E6] The method according to any one of E1 to E5, further comprising the step of applying a voltage to the edge ring to correct the thickness of the sheath on the edge ring when the amount of wear is greater than a first threshold and plasma is being generated in the chamber with the substrate placed on the substrate support.

[0085] [E7] The method according to any one of E1 to E5, further comprising the step of changing at least one parameter among the following: the power level of the high-frequency power for generating the plasma, the voltage level of the DC voltage pulse applied to the first electrode, the voltage level of the DC voltage pulse applied to the second electrode, the flow rate of the gas supplied into the chamber, the pressure inside the chamber, the pressure of the heat transfer gas supplied into the gap between the substrate support and the substrate, and the in-plane temperature distribution in the substrate support, when the amount of consumption is greater than a first threshold and the plasma is being generated in the chamber with the substrate placed on the substrate support.

[0086] [E8] The method according to E6 or E7, wherein a notification is given indicating the timing for replacing the edge ring when the amount of wear is greater than a second threshold which is greater than the first threshold.

[0087] [E9] The method according to E6 or E7, further comprising the step of cleaning the chamber while the loading of substrates into the chamber is stopped when the amount of wear is greater than a second threshold greater than the first threshold.

[0088] [E10] The process further includes replacing the edge ring while the loading of substrates into the chamber is stopped if the amount of wear is greater than a second threshold greater than the first threshold, The method according to E6 or E7, wherein the edge ring is removed from the chamber by a transport robot in a vacuum transport module connected to the chamber, while maintaining a reduced pressure in the chamber.

[0089] [E11] Chamber and, A substrate support portion provided within the chamber, comprising a first region for supporting a substrate placed thereon and a second region for supporting an edge ring placed thereon, wherein the first region includes a first electrode and the second region includes a second electrode, A gas supply unit configured to supply gas into the chamber, A plasma generation unit configured to generate plasma from gas within the chamber, A pulse generator configured to periodically apply DC voltage pulses to the first electrode and the second electrode, A sensor configured to measure the voltage value of the first electrode and the voltage value of the second electrode, Control unit and Equipped with, The control unit, (a) Control the gas supply unit and the plasma generation unit to generate plasma in the chamber, (b) When the plasma is generated in (a) above, the pulse generator is controlled to periodically apply DC voltage pulses to the first electrode and the second electrode, respectively, in order to draw ions from the plasma to the substrate support. (c) Based on the first voltage value of the first electrode and the second voltage value of the second electrode when the pulses are applied to the first electrode and the second electrode, respectively, in (b), the amount of wear of the edge ring is determined. It is structured in such a way. Plasma processing equipment.

[0090] [E12] The control unit, Determine the ratio of the time change of the second voltage value to the time change of the first voltage value. Using a predetermined relationship between the magnitude of the ratio and the wear rate of the edge ring, the wear rate of the edge ring corresponding to the determined ratio is determined. The amount of wear on the edge ring is determined by calculating the product of the determined wear rate of the edge ring and the length of time the edge ring is exposed to the plasma. A plasma processing apparatus as described in E11, configured as follows.

[0091] [E13] The control unit, Determine the ratio of the second voltage value to the first voltage value. Using the predetermined relationship between the magnitude of the ratio and the thickness of the edge ring, the thickness of the edge ring corresponding to the determined ratio is determined. A plasma processing apparatus as described in E11, configured as follows.

[0092] [E14] The control unit, The plasma generation unit and the gas supply unit are controlled to generate plasma from the processing gas in the chamber in order to process the substrate placed on the substrate support unit. Next, the plasma generation unit and the gas supply unit are controlled to generate a cleaning gas plasma within the chamber in order to perform dry cleaning of the chamber. Immediately after the dry cleaning, perform (a), (b), and (c). A plasma processing apparatus as described in E13, configured as follows.

[0093] [E15] The plasma processing apparatus according to any one of E11 to E14, wherein the pulse generator is configured to generate a pulse of negative DC voltage as the pulse of DC voltage.

[0094] [E16] The plasma processing apparatus according to any one of E11 to E15, wherein the control unit is configured to apply a voltage from a power supply to the edge ring to correct the thickness of the sheath on the edge ring when the amount of wear is greater than a first threshold and plasma is being generated in the chamber with the substrate placed on the substrate support.

[0095] [E17] Plasma processing apparatus according to any one of E11 to E15, wherein the control unit is configured to change at least one of the following parameters when the amount of consumption is greater than a first threshold, and when plasma is being generated in the chamber with a substrate placed on the substrate support: the power level of the high-frequency power for generating the plasma, the voltage level of the DC voltage pulse applied to the first electrode, the voltage level of the DC voltage pulse applied to the second electrode, the flow rate of the gas supplied into the chamber, the pressure in the chamber, the pressure of the heat transfer gas supplied to the gap between the substrate support and the substrate, and the in-plane temperature distribution in the substrate support.

[0096] [E18] The plasma apparatus according to E16 or E17, wherein the control unit is configured to give a notification indicating the timing for replacing the edge ring when the amount of wear is greater than a second threshold which is greater than the first threshold.

[0097] [E19] The plasma apparatus according to E16 or E17, wherein the control unit is configured to control the gas supply unit to supply cleaning gas into the chamber in order to clean the chamber while the loading of substrates into the chamber is stopped when the amount of consumption is greater than a second threshold greater than the first threshold.

[0098] [E20] A plasma processing apparatus described in E16 or E17, A vacuum transfer module having a transfer robot and connected to the chamber of the plasma processing apparatus, Equipped with, The control unit is configured to control the vacuum transport module so that, when the amount of wear is greater than a second threshold greater than the first threshold, the transport of substrates into the chamber is stopped, and the transport robot transports the edge ring out of the chamber in order to replace the edge ring, while maintaining a reduced pressure in the chamber. PCB processing system.

[0099] From the above description, it will be understood that the various embodiments of this disclosure are described herein for illustrative purposes and can be modified in various ways without departing from the scope and spirit of this disclosure. Accordingly, the various embodiments disclosed herein are not intended to limit the scope and spirit, and the true scope and spirit are shown by the appended claims. [Explanation of Symbols]

[0100] 1...Plasma processing apparatus, 2...Control unit, 10...Chamber, 11...Substrate support unit, 111a...First region, 111b...Second region, 121...First electrode, 122...Second electrode, 12...Plasma generation unit, 31...High-frequency power supply, 43...Pulse generator, 46...Sensor.

Claims

1. A method for determining the wear amount of the edge ring, (a) A step of generating plasma in a chamber of a plasma processing apparatus, the plasma processing apparatus includes a substrate support portion provided in the chamber, the substrate support portion includes a first region for supporting a substrate placed thereon and a second region for supporting the edge ring placed thereon, the first region includes a first electrode, and the second region includes a second electrode, the step, (b) While the plasma is being generated in (a), a step of periodically applying a DC voltage pulse to the first electrode and the second electrode in order to draw ions from the plasma to the substrate support, (c) A step of determining the amount of wear of the edge ring based on the first voltage value of the first electrode and the second voltage value of the second electrode when the pulses are applied to the first electrode and the second electrode, respectively, in (b) above, A method that includes this.

2. The above (c) is, The ratio of the time change of the second voltage value to the time change of the first voltage value is determined, Using a predetermined relationship between the magnitude of the ratio and the wear rate of the edge ring, the wear rate of the edge ring corresponding to the determined ratio is determined, The amount of wear on the edge ring is determined by calculating the product of the determined wear rate of the edge ring and the length of time the edge ring is exposed to the plasma, The method according to claim 1, including the method described in claim 1.

3. The above (c) is, To determine the ratio of the second voltage value to the first voltage value, Using a predetermined relationship between the magnitude of the ratio and the thickness of the edge ring, the thickness of the edge ring corresponding to the determined ratio is determined. The method according to claim 1, including the method described in claim 1.

4. A step of processing a substrate placed on the substrate support portion with plasma generated from a processing gas in the chamber, After the above-mentioned process of processing the substrate, a step of dry cleaning the chamber is performed, It further includes, The above (a), (b), and (c) are performed immediately after the dry cleaning process. The method according to claim 3.

5. The method according to any one of claims 1 to 4, wherein the DC voltage pulse is a negative DC voltage pulse.

6. The method according to claim 1, further comprising the step of applying a voltage to the edge ring to correct the thickness of the sheath on the edge ring when the amount of wear is greater than a first threshold and plasma is being generated in the chamber with the substrate placed on the substrate support.

7. The method according to claim 1, further comprising the step of changing at least one parameter among the following when the amount of consumption is greater than a first threshold, and when plasma is being generated in the chamber with a substrate placed on the substrate support, the power level of the high-frequency power for generating the plasma, the voltage level of the DC voltage pulse applied to the first electrode, the voltage level of the DC voltage pulse applied to the second electrode, the flow rate of the gas supplied into the chamber, the pressure in the chamber, the pressure of the heat transfer gas supplied to the gap between the substrate support and the substrate, and the in-plane temperature distribution in the substrate support, when the amount of consumption is greater than a first threshold, and when plasma is being generated in the chamber with a substrate placed on the substrate support.

8. The method according to claim 6 or 7, wherein a notification is given indicating the timing for replacing the edge ring when the amount of wear is greater than a second threshold greater than the first threshold.

9. The method according to claim 6 or 7, further comprising the step of cleaning the chamber while the loading of substrates into the chamber is stopped when the amount of consumption is greater than a second threshold greater than the first threshold.

10. The process further includes replacing the edge ring while the loading of the substrate into the chamber is stopped if the amount of wear is greater than a second threshold greater than the first threshold, The method according to claim 6 or 7, wherein the edge ring is removed from the chamber by a transport robot in a vacuum transport module connected to the chamber, while maintaining a reduced pressure in the chamber.

11. Chamber and, A substrate support portion provided within the chamber, comprising a first region for supporting a substrate placed thereon and a second region for supporting an edge ring placed thereon, wherein the first region includes a first electrode and the second region includes a second electrode, A gas supply unit configured to supply gas into the chamber, A plasma generation unit configured to generate plasma from gas within the chamber, A pulse generator configured to periodically apply DC voltage pulses to the first electrode and the second electrode, A sensor configured to measure the voltage value of the first electrode and the voltage value of the second electrode, Control unit and Equipped with, The control unit, (a) Control the gas supply unit and the plasma generation unit to generate plasma in the chamber, (b) When the plasma is generated in (a) above, the pulse generator is controlled to periodically apply DC voltage pulses to the first electrode and the second electrode, respectively, in order to draw ions from the plasma to the substrate support. (c) Based on the first voltage value of the first electrode and the second voltage value of the second electrode when the pulses are applied to the first electrode and the second electrode, respectively, in (b), the amount of wear of the edge ring is determined. It is structured in such a way. Plasma processing equipment.

12. The control unit, Determine the ratio of the time change of the second voltage value to the time change of the first voltage value. Using a predetermined relationship between the magnitude of the ratio and the wear rate of the edge ring, the wear rate of the edge ring corresponding to the determined ratio is determined. The amount of wear on the edge ring is determined by calculating the product of the determined wear rate of the edge ring and the length of time the edge ring is exposed to the plasma. The plasma processing apparatus according to claim 11, configured as described above.

13. The control unit, Determine the ratio of the second voltage value to the first voltage value. Using the predetermined relationship between the magnitude of the ratio and the thickness of the edge ring, the thickness of the edge ring corresponding to the determined ratio is determined. The plasma processing apparatus according to claim 11, configured as described above.

14. The control unit, The plasma generation unit and the gas supply unit are controlled to generate plasma from the processing gas in the chamber in order to process the substrate placed on the substrate support unit. Next, the plasma generation unit and the gas supply unit are controlled to generate a cleaning gas plasma within the chamber in order to perform dry cleaning of the chamber. Immediately after the dry cleaning, perform (a), (b), and (c). The plasma processing apparatus according to claim 13, configured as described above.

15. The plasma processing apparatus according to any one of claims 11 to 14, wherein the pulse generator is configured to generate a pulse of negative DC voltage as the pulse of DC voltage.

16. The plasma apparatus according to claim 11, wherein the control unit is configured to apply a voltage from a power supply to the edge ring to correct the thickness of the sheath on the edge ring when the amount of wear is greater than a first threshold and plasma is being generated in the chamber with the substrate placed on the substrate support.

17. The plasma processing apparatus according to claim 11, wherein the control unit is configured to change at least one of the following parameters when the amount of consumption is greater than a first threshold, and when plasma is being generated in the chamber with a substrate placed on the substrate support: the power level of the high-frequency power for generating the plasma, the voltage level of the DC voltage pulse applied to the first electrode, the voltage level of the DC voltage pulse applied to the second electrode, the flow rate of the gas supplied into the chamber, the pressure in the chamber, the pressure of the heat transfer gas supplied to the gap between the substrate support and the substrate, and the in-plane temperature distribution in the substrate support.

18. The plasma processing apparatus according to claim 16 or 17, wherein the control unit is configured to give a notification indicating the timing for replacing the edge ring when the amount of wear is greater than a second threshold which is greater than the first threshold.

19. The plasma apparatus according to claim 16 or 17, wherein the control unit is configured to control the gas supply unit to supply cleaning gas into the chamber in order to clean the chamber while the loading of substrates into the chamber is stopped when the amount of consumption is greater than a second threshold greater than the first threshold.

20. A plasma processing apparatus according to claim 16 or 17, A vacuum transfer module having a transfer robot and connected to the chamber of the plasma processing apparatus, Equipped with, The control unit is configured to control the vacuum transport module so that, when the amount of wear is greater than a second threshold greater than the first threshold, the transport of substrates into the chamber is stopped, and the transport robot transports the edge ring out of the chamber in order to replace the edge ring, while maintaining a reduced pressure in the chamber. PCB processing system.

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