Substrate processing system and gas measurement method

Abstract

To provide a substrate processing system in which deterioration in a filament is suppressed and which therefore enables stability of gas measurement to be improved, and a gas measurement method for the substrate processing system.SOLUTION: A substrate processing system is provided, including: a chamber; a substrate support unit that is provided in the chamber and supports a substrate; a gas supply unit supplying processing gas into the chamber; an RF power source supplying a RF signal to generate plasma of the processing gas in the chamber; a gas measurement unit measuring gas in the plasma; and a control unit. The gas measurement unit has a first filament and a second filament having a material different from that of the first filament.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing system and a gas measurement method. [Background technology]

[0002] Patent Document 1 discloses a substrate processing system including a gas analyzer that collects and analyzes gas in a chamber via a gas collection pipe and a valve, and discloses the use of, for example, a quadrupole mass analyzer as the gas analyzer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-27787 Summary of the Invention [Problem to be solved by the invention]

[0004] In one aspect, the present disclosure provides a substrate processing system and a gas measurement method that suppresses filament degradation and improves the stability of gas measurement. [Means for solving the problem]

[0005] In order to solve the above problem, according to one aspect, there is provided a substrate processing system comprising: a chamber; a substrate support section disposed within the chamber and configured to support a substrate; a gas supply section configured to supply a processing gas into the chamber; an RF power supply section configured to supply an RF signal to generate a plasma of the processing gas within the chamber; a gas measurement section configured to measure a gas in the plasma; and a control section, wherein the gas measurement section has a first filament and a second filament made of a material different from that of the first filament. [Effects of the Invention]

[0006] According to one aspect, it is possible to provide a substrate processing system and a gas measurement method that suppress deterioration of a filament and improve the stability of gas measurement. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an example of a plasma processing system. [Figure 2] FIG. 1 is a diagram illustrating a configuration of an example of a plasma processing apparatus. [Figure 3] FIG. 10 is a configuration diagram of another example of a plasma processing apparatus. [Figure 4] FIG. 2 is a configuration diagram of an example of a gas measurement unit according to the first embodiment. [Figure 5] FIG. 10 is a configuration diagram of an example of a gas measurement unit according to a second embodiment. [Figure 6] FIG. 4 is a configuration diagram of an example of a gas measurement unit according to a reference example. [Figure 7] 1 is an example of a flowchart illustrating gas measurement in a process. [Figure 8] 10 is another example of a flowchart illustrating gas measurement in a process. [Figure 9] 10 is yet another example of a flowchart illustrating gas measurement in a process. [Figure 10] 10 is yet another example of a flowchart illustrating gas measurement in a process. [Figure 11] 6 is a graph showing an example of ion current values detected by a plurality of gas measuring devices. DETAILED DESCRIPTION OF THE INVENTION

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

[0009] A plasma processing system (substrate processing system) will be described with reference to Fig. 1. Fig. 1 is a configuration diagram of an example of a plasma processing system. Fig. 2 is a configuration diagram of an example of a plasma processing apparatus 1. Fig. 3 is a configuration diagram of another example of the plasma processing apparatus 1.

[0010] As shown in FIG. 1, in one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0011] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Various types of plasma generating units may be used, including alternating current (AC) plasma generating units and direct current (DC) plasma generating units. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes a radio frequency (RF) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 200 kHz to 150 MHz.

[0012] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The controller 2 may be configured to control each element of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1. The controller 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on programs stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0013] An exemplary configuration of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1 will be described below. As shown in FIG. 2, the capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, an exhaust system 40, and a gas measurement unit 5. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The sidewall 10a is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0014] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W and an annular region (ring support surface) 111b for supporting the ring assembly 112. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. In one embodiment, the main body 111 includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base functions as a lower electrode. The electrostatic chuck is disposed on the base. The upper surface of the electrostatic chuck has the substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck, the ring assembly 112, and the substrate W to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a.

[0015] 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 multiple gas inlets 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 from the multiple gas inlets 13c. The showerhead 13 also includes a conductive member. The conductive member of the showerhead 13 functions as an 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 sidewall 10a.

[0016] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0017] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to the conductive member of the substrate support 11 and / or the conductive member of the showerhead 13. This causes plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0018] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13 via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 13 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13. The second RF generating unit 31b is coupled to the conductive members of the substrate support 11 via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a frequency lower than that of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated bias RF signals are supplied to the conductive members of the substrate support 11. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0019] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, the first and second DC signals may be pulsed. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0020] The exhaust system 40 may be connected to, for example, a gas outlet 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure 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. As a result, gases in the plasma processing chamber 10 are exhausted by the exhaust system 40 (see the black arrows).

[0021] The gas measurement unit 5 (5A, 5B) collects and measures gases in the plasma processing chamber 10. As shown in FIG. 2, the gas measurement unit 5 (5A) includes a gas measurement device 51, a valve 52, and a pipe 53. One end of the pipe 53 is connected to a gas collection port 10b provided in a sidewall 10a of the plasma processing chamber 10. The other end of the pipe 53 is connected to the gas measurement device 51. The pipe 53 is also provided with a valve 52.

[0022] The gas measurement device 51 may be, for example, a quadrupole mass analyzer (QMS). A quadrupole mass analyzer separates gases based on mass, allowing for measurement of trace components. The quadrupole mass analyzer can also measure gas dissociation caused by plasma.

[0023] A quadrupole mass analyzer has an ion source section, a mass analysis section, and a detection section. The ion source section is equipped with a filament (filaments 501 and 502 described below) and a power supply. The filament power supply applies a voltage to the filament. When the voltage is applied, the filament becomes hot and emits thermoelectrons. The emitted thermoelectrons collide with gas and ionize it. The mass analysis section applies a DC or AC voltage to four electrodes (quadrupoles) to allow ions of a predetermined mass to pass through. The detection section detects the ions that have passed through the mass analysis section.

[0024] The valve 52 opens and closes the pipe 53 and creates a pressure difference between the pressure inside the plasma processing chamber 10 and the pressure on the gas measuring device 51 side.

[0025] 3, the gas measurement unit 5 (5B) may be a differential pumping system. That is, the gas measurement unit 5 includes a gas measurement device 51, a valve 52, a pipe 53, and an exhaust system 54. The exhaust system 54 may be connected, for example, to the pipe 53 between the valve 52 and the gas measurement device 51. The exhaust system 54 may include a pressure regulating valve and a vacuum pump. The pressure regulating valve adjusts the pressure of the gas supplied to the gas measurement device 51. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof. As a result, gas in the plasma processing chamber 10 is exhausted by the exhaust system 40 (see black arrows). Also, gas in the pipe 53 is exhausted by the exhaust system 54 (see black arrows).

[0026] The gas measurement device 51 that measures gas using a filament will be described as a quadrupole mass spectrometer, but is not limited to this. The gas measurement device 51 may be, for example, a residual gas analyzer (RGA).

[0027] Next, the gas measurement unit 5 will be further described with reference to FIGS. 4 to 6. FIG. 4 is a configuration diagram of an example of a gas measurement unit 5A1 according to the first embodiment. FIG. 5 is a configuration diagram of an example of a gas measurement unit 5A2 according to the second embodiment. FIG. 6 is a configuration diagram of an example of a gas measurement unit 5X according to a reference example. In the following description, the gas measurement units 5 (5A1, 5A2) will be described using an example configuration that does not include a differential pumping system (see FIG. 2), but the present invention is not limited to this and may also include a differential pumping system (see FIG. 3).

[0028] The gas measurement unit 5A1 according to the first embodiment shown in FIG. 4 includes a gas measurement device 51, a valve 52, and a pipe 53. The gas measurement device 51 includes a plurality of filaments and is configured to be able to select the filament to be used during gas measurement. In the example shown in FIG. 4, the gas measurement device 51 includes two filaments 501 and 502. The control unit 2 (see FIG. 1) controls the filament power supply of the gas measurement device 51 to select the filament 501 or 502 to which a voltage is applied. That is, the control unit 2 (see FIG. 1) controls the filament power supply of the gas measurement device 51 to select the filament 501 or 502 to be used during gas measurement.

[0029] The gas measurement unit 5A2 according to the second embodiment shown in FIG. 5 includes a plurality of gas measurement devices 51, a plurality of valves 52, and a pipe 53. One end of the pipe 53 is connected to the gas sampling port 10b (see FIG. 2). The other end of the pipe 53 branches, and the other branched ends are connected to the valves 52 and the gas measurement devices 51, respectively. Each gas measurement device 51 includes a filament. In the example shown in FIG. 4, the gas measurement unit 5A2 includes a gas measurement device 51 including a filament 501 and a gas measurement device 51 including a filament 502. The control unit 2 (see FIG. 1) can select the gas measurement device 51 to be used during gas measurement by controlling the opening and closing of the valve 52. That is, the control unit 2 (see FIG. 1) can select the filament 501 or 502 to be used during gas measurement by controlling the opening and closing of the valve 52.

[0030] Here, the filaments 501 and 502 are made of different materials. For example, the filament 501 is a filament (Ir-based filament) made of a material containing iridium (Ir). The filament 502 is a filament (W-based filament) made of a material containing tungsten (W). The filaments 501 and 502 may have additives such as yttria (Y) or rhenium (Re) introduced into their substrates. Furthermore, the filaments 501 and 502 may have a coating layer made of a material containing yttria (Y), rhenium (Re), or the like formed on the surface of the filament substrate.

[0031] Here, the filament 501 formed of a material containing iridium (Ir) can stably measure gases in processes using gases containing oxygen atoms (e.g., O2 gas, etc.) used in processes such as ashing, cleaning, etc. On the other hand, in processes using gases containing halogen atoms (e.g., CF4 gas, C4F8 gas, C5F8 gas, C4F6 gas, CHF3 gas, CH2F2 gas, Cl2 gas, HBr gas, etc.), the filament 501 is subject to rapid wear and deterioration, and may be damaged in a short period of time.

[0032] Furthermore, the filament 502 made of a material containing tungsten (W) can stably measure gases in processes using gases containing halogen atoms. On the other hand, in processes using gases containing oxygen atoms, the filament 502 is subject to rapid wear and deterioration, and may be damaged in a short period of time.

[0033] 6 includes a gas measuring device 51, a valve 52, and a pipe 53. The gas measuring device 51 includes a filament 500 of one type.

[0034] <Processing method> Next, gas measurement in a process will be described with reference to FIGS. 7 to 10. FIG.

[0035] FIG. 7 is an example of a flowchart illustrating gas measurement in a process.

[0036] In step S101, the substrate W is transferred into the plasma processing chamber 10 and is supported by the substrate support 11.

[0037] In step S102, the control unit 2 reads the processing conditions. The processing conditions are stored in advance in the memory unit 2a2. One processing set includes one or more different processing steps, and each processing step includes the type of gas supplied from the gas supply unit 20 to the plasma processing chamber 10, the gas flow rate, the pressure inside the plasma processing space 10s, the voltage of the power supply 30, etc. The conditions for each processing step also include the type of filament used for gas measurement.

[0038] In step S103, the control unit 2 determines the filament of the next processing step specified in the processing conditions. If the specified filament is the first filament, the control unit 2 proceeds to step S104. If the specified filament is the second filament, the control unit 2 proceeds to step S105.

[0039] In step S104, the control unit 2 selects the filament (first filament) 501. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 501. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 501 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 502.

[0040] In step S105, the control unit 2 selects the filament (second filament) 502. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 502. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 502 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 501.

[0041] In step S106, the control unit 2 executes the processing step by controlling the plasma processing apparatus 1. Here, the gas is measured using the selected filament.

[0042] In step S107, the control unit 2 determines whether all the processing steps have been completed. If all the processing steps have not been completed (S107: No), the control unit 2 returns to step S102, selects a filament according to the next processing step, and performs processing (S102 to S106). If all the processing steps have been completed (S107: Yes), the control unit 2 proceeds to step S108.

[0043] In step S108, the substrate W is transferred (unloaded) from the plasma processing chamber 10.

[0044] FIG. 8 is another example of a flowchart illustrating gas measurement in a process.

[0045] In step S201, the substrate W is transferred into the plasma processing chamber 10 and is supported by the substrate support 11.

[0046] In step S202, the control unit 2 reads the processing conditions. The processing conditions are stored in advance in the memory unit 2a2. One processing condition includes one or more different processing steps, and each processing step includes the type of gas supplied from the gas supply unit 20 to the plasma processing chamber 10, the gas flow rate, the pressure inside the plasma processing space 10s, the voltage of the power supply 30, etc.

[0047] In step S203, the control unit 2 determines whether the processing gas to be used in the next processing step specified in the processing conditions contains oxygen atoms. If the processing gas contains oxygen atoms (S203 YES), the control unit 2 proceeds to step S204. If the processing gas does not contain oxygen atoms (S203 NO), the control unit 2 proceeds to step S205.

[0048] In step S204, the control unit 2 selects the filament (first filament) 501. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 501. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 501 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 502.

[0049] In step S205, the control unit 2 selects the filament (second filament) 502. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 502. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 502 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 501.

[0050] In step S206, the control unit 2 executes the processing step by controlling the plasma processing apparatus 1. Here, the gas is measured using the selected filament.

[0051] In step S207, the control unit 2 determines whether all the processing steps have been completed. If all the processing steps have not been completed (S207: No), the control unit 2 returns to step S202, selects a filament according to the next processing step, and performs processing (S202 to S206). If all the processing steps have been completed (S207: Yes), the control unit 2 proceeds to step S208.

[0052] In step S208, the substrate W is transferred (unloaded) from the plasma processing chamber 10.

[0053] FIG. 9 is yet another example of a flowchart illustrating gas measurement in a process.

[0054] In step S301, the substrate W is transferred into the plasma processing chamber 10 and is supported by the substrate support 11.

[0055] In step S302, the control unit 2 reads the processing conditions. The processing conditions are stored in advance in the memory unit 2a2. One processing condition includes one or more different processing steps, and each processing step includes the type of gas supplied from the gas supply unit 20 to the plasma processing chamber 10, the gas flow rate, the pressure inside the plasma processing space 10s, the voltage of the power supply 30, etc.

[0056] In step S303, the control unit 2 determines whether the processing gas to be used in the next processing step specified in the processing conditions contains halogen atoms. If the processing gas contains halogen atoms (S303 YES), the control unit 2 proceeds to step S304. If the processing gas does not contain halogen atoms (S303 NO), the control unit 2 proceeds to step S305.

[0057] In step S304, the control unit 2 selects the filament (second filament) 502. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 502. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 502 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 501.

[0058] In step S305, the control unit 2 selects the filament (first filament) 501. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 501. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 501 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 502.

[0059] In step S306, the control unit 2 executes the processing step by controlling the plasma processing apparatus 1. Here, the gas is measured using the selected filament.

[0060] In step S307, the control unit 2 determines whether all the processing steps have been completed. If all the processing steps have not been completed (S307: No), the control unit 2 returns to step S302, selects a filament according to the next processing step, and performs processing (S302 to S306). If all the processing steps have been completed (S307: Yes), the control unit 2 proceeds to step S308.

[0061] In step S308, the substrate W is transferred (unloaded) from the plasma processing chamber 10.

[0062] FIG. 10 is yet another example of a flowchart illustrating gas measurement in a process.

[0063] In step S401, the substrate W is transferred into the plasma processing chamber 10 and is supported by the substrate support 11.

[0064] In step S402, the control unit 2 reads the processing conditions. The processing conditions are stored in advance in the memory unit 2a2. One processing condition includes one or more different processing steps, and each processing step includes the type of gas supplied from the gas supply unit 20 to the plasma processing chamber 10, the gas flow rate, the pressure inside the plasma processing space 10s, the voltage of the power supply 30, etc.

[0065] In step S403, the control unit 2 determines whether the processing gas to be used in the next processing step specified in the processing conditions contains oxygen atoms. If the processing gas contains oxygen atoms (S403 YES), the control unit 2 proceeds to step S404. If the processing gas does not contain oxygen atoms (S403 NO), the control unit 2 proceeds to step S406.

[0066] In step S404, the control unit 2 determines whether the processing gas to be used in the next processing step specified in the processing conditions contains halogen atoms. If the processing gas contains halogen atoms (S404 YES), the control unit 2 proceeds to step S405. If the processing gas does not contain halogen atoms (S404 NO), the control unit 2 proceeds to step S407.

[0067] In step S405, the control unit 2 determines whether the ratio of the flow rate of the gas containing oxygen atoms to the total gas flow rate ((flow rate of the gas containing oxygen atoms (sccm) / total gas flow rate (sccm)) × 100%) of the processing gas to be used in the next processing step specified in the processing conditions is equal to or greater than a predetermined threshold value (e.g., 30%). If the processing gas contains 30% or more of gas containing oxygen atoms (S405 YES), the control unit 2 proceeds to step S407. If the processing gas does not contain 30% or more of gas containing oxygen atoms (S405 NO), the control unit 2 proceeds to step S408.

[0068] In step S406, the control unit 2 determines whether the processing gas to be used in the next processing step specified in the processing conditions contains halogen atoms. If the processing gas contains halogen atoms (S406 YES), the control unit 2 proceeds to step S408. If the processing gas does not contain halogen atoms (S406 NO), the control unit 2 proceeds to step S407.

[0069] In step S407, the control unit 2 selects the filament (first filament) 501. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 501. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 501 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 502.

[0070] In step S408, the control unit 2 selects the filament (second filament) 502. Specifically, in the gas measurement unit 5A1 shown in Fig. 4, the control unit 2 controls the filament power supply to apply a voltage to the filament 502. In the gas measurement unit 5A2 shown in Fig. 5, the control unit 2 opens the valve 52 corresponding to the gas measurement device 51 having the filament 502 and closes the valve 52 corresponding to the gas measurement device 51 having the filament 501.

[0071] In step S409, the control unit 2 executes the processing step by controlling the plasma processing apparatus 1. Here, the gas is measured using the selected filament.

[0072] In step S410, the control unit 2 determines whether all the processing steps have been completed. If all the processing steps have not been completed (S410: No), the control unit 2 returns to step S402, selects a filament according to the next processing step, and performs processing (S402 to S409). If all the processing steps have been completed (S410: Yes), the control unit 2 proceeds to step S411.

[0073] In step S411, the substrate W is transferred (unloaded) from the plasma processing chamber 10.

[0074] That is, in a process of supplying a gas containing oxygen atoms to the plasma processing chamber 10, the control unit 2 selects the filament (first filament) 501. In a process of supplying a gas containing halogen atoms to the plasma processing chamber 10, the control unit 2 selects the filament (second filament) 502. Also, in a process of supplying a gas containing oxygen atoms and a gas containing halogen atoms to the plasma processing chamber 10, the control unit 2 selects the filament (first filament) 501 if the proportion of the gas containing oxygen atoms is equal to or greater than a predetermined threshold (e.g., 30%), and selects the filament (second filament) 502 if the proportion of the gas containing oxygen atoms is less than the predetermined threshold (e.g., 30%). Also, in a process of not supplying a gas containing oxygen atoms to the plasma processing chamber 10 and not supplying a gas containing halogen atoms to the plasma processing chamber 10, the control unit 2 selects the filament (first filament) 501.

[0075] In a plasma processing system using a gas measurement unit 5X (see FIG. 6) according to a reference example, different processes are successively performed on a substrate W by switching process gases within a single plasma processing chamber 10. For example, a process of supplying a gas containing oxygen atoms and a process of supplying a gas containing halogen atoms are performed. In this case, the filament 500 may deteriorate, and the deterioration of the filament 500 may reduce the stability of gas measurement.

[0076] In contrast, in a plasma processing system using gas measurement units 5A1 and 5A2 (see FIGS. 4 and 5) according to this embodiment, different processes are successively performed on a substrate W by switching process gases within a single plasma processing chamber 10. For example, a process of supplying a gas containing oxygen atoms and a process of supplying a gas containing halogen atoms are performed. In this case, gas measurement is performed using a filament (first filament) 501 made of a material containing iridium (Ir) in the process of supplying the gas containing halogen atoms. Furthermore, gas measurement is performed using a filament (second filament) 502 made of a material containing tungsten (W) in the process of supplying the gas containing halogen atoms. This can suppress deterioration of the filaments 501 and 502. Furthermore, suppressing a decrease in stability of gas measurement due to deterioration of the filaments 501 and 502 can improve the stability of gas measurement.

[0077] In addition, in a process in which a gas containing oxygen atoms is not supplied to the plasma processing chamber 10 and a gas containing halogen atoms is not supplied to the plasma processing chamber 10, gas measurement is performed using a filament (first filament) 501 formed of a material containing iridium (Ir).

[0078] <Calibration method> Next, the calibration method will be described with reference to Fig. 11. Fig. 11 is a graph showing an example of ion current values detected by a plurality of gas measuring devices 51. Here, the vertical axis represents the ion current value, and the horizontal axis represents time.

[0079] In gas measurement unit 5A2 (see FIG. 5), control unit 2 opens both valves 52 and simultaneously detects gas using both gas measurement device 51 having filament 501 and gas measurement device 51 having filament 502. For example, the ion current value of gas measurement device 51 having filament 501 is shown by a solid line, and the ion current value of gas measurement device 51 having filament 502 is shown by a dashed line.

[0080] In this way, calibration can be performed for the same gas by detecting the ion current values using the different gas measuring devices 51 of the filaments 501 and 502. For example, A calibration coefficient can be calculated from the ion current value (solid line) of the gas measuring device 51 having the filament 501 and the ion current value (dashed line) of the gas measuring device 51 having the filament 502.

[0081] Although not shown, in the gas measuring unit 5A1 (see FIG. 4), when the gas in the plasma processing chamber 10 is in a steady state, the control unit 2 applies a voltage to one filament 501 to detect the ion current value, and then applies a voltage to the other filament 502 to detect the ion current value.

[0082] This allows calibration to be performed by detecting the ion current values using different filaments 501 and 502 for gas in the same state.

[0083] The above describes embodiments of the plasma processing system, but the present disclosure is not limited to the above embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure as described in the claims. [Explanation of symbols]

[0084] 10b Gas sampling port 5 Gas measurement section 5A Gas measurement section 5B Gas measurement section 51 Gas measuring equipment 52 Valve 53 Piping 54 Exhaust System 501,502 filament 501 Filament 502 Filament

Claims

1. a chamber; a substrate support provided in the chamber and configured to support a substrate; a gas supply unit that supplies a processing gas into the chamber; an RF power supply that provides an RF signal to create a plasma of the process gas within the chamber; a gas measurement unit that measures gas in the plasma; a control unit, The gas measurement unit a first gas metering device having a first filament; a second gas metering device having a second filament made of a different material than the first filament; Substrate processing system.

2. The control unit Based on the gas species under processing conditions, controlling the filament to be used for measurement to be selected from the first filament and the second filament; The substrate processing system of claim 1 .

3. The processing conditions include a plurality of processing steps, The control unit Based on the gas type for each process, controlling the filament to be used for measurement to be selected from the first filament and the second filament; The substrate processing system of claim 2 .

4. the first filament is a filament containing iridium, the second filament is a filament containing tungsten; The substrate processing system according to any one of claims 1 to 3.

5. The control unit In a process of supplying a gas containing oxygen atoms to the chamber, the filament containing iridium is selected and controlled. The substrate processing system according to claim 4 .

6. The control unit controlling the supply of a gas containing halogen atoms to the chamber to select the filament containing tungsten; The substrate processing system according to claim 4 .

7. The control unit In a process of supplying a gas containing oxygen atoms and a gas containing halogen atoms to the chamber, if the ratio of the flow rate of the gas containing oxygen atoms to the total gas flow rate is 30% or more, a filament containing iridium is selected, and if the ratio is less than 30%, a filament containing tungsten is selected. The substrate processing system according to claim 4 .

8. The control unit controlling the filament containing iridium to be selected in a process in which a gas containing oxygen atoms is not supplied to the chamber and a gas containing halogen atoms is not supplied to the chamber; The substrate processing system according to claim 4 .

9. The control unit Based on the filament specified in the processing conditions, controlling the filament to be used for measurement to be selected from the first filament and the second filament; The substrate processing system of claim 1 .

10. 1. A gas measurement method for a substrate processing system comprising: a chamber; a substrate support unit provided in the chamber and supporting a substrate; a gas supply unit that supplies a process gas into the chamber; an RF power supply that supplies an RF signal to generate plasma of the process gas in the chamber; a gas measurement unit that measures gas in the plasma; and a control unit, wherein the gas measurement unit has a first filament and a second filament made of a material different from that of the first filament, the first filament is a filament containing iridium, the second filament is a filament containing tungsten, selecting a filament to be used for measurement from the first filament and the second filament based on the gas species under the processing conditions; In a process of supplying a gas containing oxygen atoms and a gas containing halogen atoms to the chamber, if the ratio of the flow rate of the gas containing oxygen atoms to the total gas flow rate is 30% or more, a filament containing iridium is selected, and if the ratio is less than 30%, a filament containing tungsten is selected. Gas measurement methods.

11. The processing conditions include a plurality of processing steps, selecting a filament to be used for measurement from the first filament and the second filament based on the type of gas in each treatment step; The gas measurement method according to claim 10.

12. Among the plurality of processing steps, a processing step in which a gas containing oxygen atoms is supplied to the chamber selects a filament containing iridium. The gas measurement method according to claim 11.

13. Among the plurality of processing steps, a processing step in which a gas containing halogen atoms is supplied to the chamber selects the filament containing tungsten. The gas measurement method according to claim 11.

14. Among the plurality of processing steps, a processing step in which a gas containing oxygen atoms is not supplied to the chamber and a gas containing halogen atoms is not supplied to the chamber, is selected, and The gas measurement method according to claim 11.

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