Substrate processing apparatus, substrate processing method, and program

Abstract

A substrate processing apparatus according to the present disclosure comprises: a chamber; a substrate support unit disposed in the chamber; a pressure adjustment valve configured to be capable of adjusting pressure in the chamber; a gas supply unit configured to supply gas to the chamber; and a control unit configured to execute a repetitive process that is periodically repeated on a substrate on the basis of the same recipe. The control unit is configured to execute, in each cycle of the repetitive process: (a) supplying gas from the gas supply unit to the chamber; (b) controlling the pressure adjustment valve on the basis of a control parameter related to the opening degree of the pressure adjustment valve; (c) acquiring pressure information related to the pressure in the chamber during (b); and (d) updating the control parameter on the basis of the pressure information.

Description

Substrate processing apparatus, substrate processing method, and program

[0001] An exemplary embodiment of the present disclosure relates to a substrate processing apparatus, a substrate processing method, and a program.

[0002] Japanese Patent Application Laid-Open No. 2003-129999 discloses a technique for generating plasma from a gas supplied into a chamber of a plasma processing apparatus and detecting light from the plasma.

[0003] JP 2016-100547 A

[0004] The present disclosure provides techniques for appropriately controlling the pressure within a chamber.

[0005] In one exemplary embodiment of the present disclosure, there is provided a substrate processing apparatus including a chamber, a substrate support disposed within the chamber, a pressure regulator configured to adjust a pressure within the chamber, a gas supply unit configured to supply a gas to the chamber, and a control unit configured to execute a repetitive process that is periodically repeated on a substrate based on the same recipe, the control unit being configured to, in each cycle of the repetitive process, (a) supply a gas from the gas supply unit to the chamber, (b) control the pressure regulator valve based on a control parameter related to an opening degree of the pressure regulator valve, (c) obtain pressure information related to the pressure within the chamber during (b), and (d) update the control parameter based on the pressure information.

[0006] According to one exemplary embodiment of the present disclosure, a technique for appropriately controlling the pressure in a chamber can be provided.

[0007] 1 is a diagram for explaining an example of the configuration of a plasma processing system. FIG. 2 is a diagram for explaining an example of the configuration of a plasma processing apparatus. FIG. 3 is a block diagram showing an example of the configuration of a pressure adjustment system 100. FIG. 4 is a flowchart showing an example of the operation of the pressure valve control device 50 according to the first embodiment. FIG. 5 is a flowchart showing an example of the operation of the pressure valve control device 50 according to the second embodiment. FIG. 6 is a diagram showing an example of a control block diagram of the pressure valve control device 50 according to the second embodiment. FIG. 7 is a flowchart showing an example of the operation of the pressure valve control device 50 according to the third embodiment. FIG. 8 is a diagram showing an example of the operation of the pressure valve control device 50 according to the fourth embodiment. FIG. 9 is a diagram showing an example of the operation of the pressure valve control device 50 according to the fourth embodiment.

[0008] Hereinafter, each embodiment of the present disclosure will be described.

[0009] In one exemplary embodiment, a substrate processing apparatus is provided, the substrate processing apparatus including: a chamber, a substrate support disposed within the chamber, a pressure regulator configured to adjust the pressure within the chamber, a gas supply unit configured to supply gas to the chamber, and a controller configured to perform a repetitive process that is periodically repeated on a substrate based on the same recipe, the controller being configured, in each cycle of the repetitive process, to (a) supply gas from the gas supply unit to the chamber, (b) control the pressure regulator valve based on a control parameter related to an opening degree of the pressure regulator valve, (c) obtain pressure information related to the pressure within the chamber during (b), and (d) update the control parameter based on the pressure information.

[0010] In one exemplary embodiment, the control parameters include a manipulated variable sequence that indicates the manipulated variable of the pressure regulator valve over time.

[0011] In one exemplary embodiment, the manipulated variable sequence has a length corresponding to one period of the iterative process.

[0012] In one exemplary embodiment, the controller updates the manipulated variable sequence at (d) before the next cycle begins.

[0013] In one exemplary embodiment, the pressure information includes error information regarding the error between the set value of the pressure in the chamber and the actual measured value of the pressure in the chamber, and in (d), the control unit updates the control parameters based on the error information so as to suppress the error.

[0014] In one exemplary embodiment, the error information includes an error sequence indicating the value of the error over time, and the control unit updates the control parameters based on the error sequence in (d) so that the error sequence is suppressed.

[0015] In one exemplary embodiment, the controller updates the control parameters in (d) based on the output of a low-pass filter applied to the error sequence.

[0016] In one exemplary embodiment, the control unit further executes (e) determining whether the pressure information satisfies a learning termination condition, and if it is determined in (e) that the pressure information does not satisfy the learning termination condition, it updates the control parameters based on the pressure information in (d), and if it is determined in (e) that the pressure information satisfies the learning termination condition, it restricts the update of the control parameters in (d).

[0017] In one exemplary embodiment, the training termination condition includes the error convergence rate being below a given threshold.

[0018] In one exemplary embodiment, the training termination condition includes the magnitude of the error being less than or equal to a given threshold.

[0019] In one exemplary embodiment, the learning termination condition includes the number of times the control parameters are updated in the iterative process being equal to or greater than a given threshold.

[0020] In one exemplary embodiment, the repeated process is a process on the same substrate.

[0021] In one exemplary embodiment, a substrate processing method is provided using a substrate processing apparatus including a chamber, a substrate support disposed within the chamber, a pressure regulator configured to adjust a pressure within the chamber, and a gas supply unit configured to supply a gas to the chamber, the method including periodically repeating a process on a substrate based on the same recipe, wherein each cycle of the repetitive process includes: (a) supplying gas from the gas supply unit to the chamber; (b) controlling the pressure regulator valve based on a control parameter related to an opening degree of the pressure regulator valve; (c) acquiring pressure information related to the pressure within the chamber during (b); and (d) updating the control parameter based on the pressure information.

[0022] In one exemplary embodiment, a program is provided that causes a computer of a substrate processing apparatus to execute a repetitive process that is periodically repeated on a substrate based on the same recipe, the substrate processing apparatus including a chamber, a substrate support disposed in the chamber, a pressure regulator valve configured to adjust the pressure in the chamber, and a gas supply unit configured to supply a gas to the chamber, wherein each cycle of the repetitive process includes (a) supplying a gas from the gas supply unit to the chamber, (b) controlling the pressure regulator valve based on a control parameter related to an opening degree of the pressure regulator valve, (c) acquiring pressure information related to the pressure in the chamber in (b), and (d) updating the control parameter based on the pressure information.

[0023] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or similar elements are designated by the same reference numerals, and redundant explanations will be omitted. Unless otherwise specified, the positional relationships, such as up, down, left, and right, will be described based on the positional relationships shown in the drawings. The dimensional ratios in the drawings do not represent actual ratios, and the actual ratios are not limited to the ratios shown in the drawings.

[0024] <Example of Plasma Processing System> FIG. 1 is a diagram illustrating an example of the 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 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.

[0025] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma generated in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0026] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 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 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 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. This program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0027] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0028] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10 (also simply referred to as the "chamber"), a gas supply unit 20, a power supply 30, and an exhaust system 40. 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 process 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 plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0029] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting a substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0030] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32, which will be described later, may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Furthermore, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0031] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0032] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow passage 1110a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the backside of the substrate W and the central region 111a.

[0033] The showerhead 13 is configured to introduce at least one process 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 process 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 at least one upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0034] 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.

[0035] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma 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 at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0036] 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 at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF 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 at least one lower electrode and / or at least one upper electrode.

[0037] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 100 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0038] 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 the at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0039] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one period. 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.

[0040] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve 42 and a vacuum pump 44. The pressure regulating valve 42 regulates the pressure in the plasma processing space 10s. In this embodiment, the conductance of the pressure regulating valve 42 changes depending on its opening degree. A pressure valve control device 50 may be provided to control the pressure in the plasma processing space 10s by controlling the opening degree of the pressure regulating valve 42. The pressure valve control device 50 may be a part of the plasma processing apparatus 1 or may be external to the plasma processing apparatus 1. The vacuum pump 44 may include a turbomolecular pump, a dry pump, or a combination thereof. At least a part of the control unit 2, the pressure regulating valve 42, and / or the pressure valve control device 50 may constitute a pressure adjustment system 100.

[0041] In one embodiment, at least a portion of the operation of the plasma processing apparatus 1 may be specified by a recipe stored in the storage unit 2a2. In one embodiment, the recipe specifies the operation of each element of the plasma processing apparatus 1. For example, the recipe specifies the operation of the gas supply unit 20 and the power supply 30. In one example, the recipe may specify the transition of the gas supply amount in a given process for processing a substrate, the waveform of the voltage to be applied in the process, and the like.

[0042] Hereinafter, an operation of the plasma processing apparatus 1 specified based on a recipe will be referred to as a “process.” In one example, the process includes at least one of supplying a gas from the gas supply unit 20 to the inside of the plasma processing chamber 10 and applying a voltage to the inside of the plasma processing chamber 10 to generate plasma.

[0043] In one embodiment, the plasma processing apparatus 1 processes substrates through a repetitive process that is periodically repeated on the substrate based on the same recipe. More specifically, the plasma processing apparatus 1 can process substrates through a first to a Jth cycle (where J is an integer equal to or greater than 2) of processes that are all based on the same recipe. In one embodiment, the plasma processing apparatus 1 processes the same substrate through the repetitive process.

[0044] Hereinafter, the multiple time divisions included in a period will be referred to as “steps.” That is, one period can be divided into multiple steps in terms of time.

[0045] 3 is a block diagram showing an example of the configuration of the pressure adjustment system 100. The pressure adjustment system 100 may include at least a part of the control unit 2, a pressure adjustment valve 42, and a pressure valve control device 50. The pressure valve control device 50 has a communication unit 51, a pressure information acquisition unit 52, an update unit 53, an opening control unit 54, and a storage unit 56. Note that the control unit 2 may have some or all of the configuration included in the pressure valve control device 50. In one embodiment, some or all of the functions performed by the configuration included in the pressure valve control device 50 may be executed by the control unit 2.

[0046] The communication unit 51 may be an interface configured to communicate between the pressure valve control device 50 and the control unit 2. The communication unit 51 receives control data from the control unit 2. The communication unit 51 may communicate with each component of the control unit 2 via the communication interface 2a3. The communication unit 51 may store some or all of the control data received from the control unit 2 in the memory unit 56. Furthermore, the communication unit 51 may transmit some or all of the control data received from the control unit 2 to the pressure information acquisition unit 52 and the update unit 53.

[0047] The control data received by the communication unit 51 may include a control parameter related to the opening degree of the pressure regulating valve 42. The control parameter may be an operation amount sequence indicating the operation amount of the pressure regulating valve 42 over time. The operation amount sequence may be the operation amount of the pressure regulating valve 42 at each of a plurality of points in time. Note that in the present disclosure, the "operation amount" may be an absolute value of the opening degree of the pressure regulating valve 42 (e.g., "7 mm" and "8 mm"), or may be a relative value with respect to the opening degree at another point in time (e.g., "opening degree at the previous point in time + 1 mm").

[0048] The manipulated variable sequence may include multiple elements. Each element of the manipulated variable sequence may indicate the manipulated variable of the pressure regulating valve 42 at a given time. Each element of the manipulated variable sequence may indicate the manipulated variable of the pressure regulating valve 42 at each step in a cycle. In one example, a manipulated variable sequence having K elements (where K is an integer greater than or equal to 2) is represented as a K-by-1 vector. The manipulated variable sequence may have a length corresponding to one cycle of the iterative process.

[0049] The communication unit 51 receives a measurement value of the pressure inside the plasma processing chamber 10 (hereinafter also referred to as "chamber pressure") measured by the pressure sensor 60. The communication unit 51 can receive the measurement value of the chamber pressure from the pressure sensor 60. The communication unit 51 can receive the measurement value of the chamber pressure via the control unit 2.

[0050] The communication unit 51 receives a chamber pressure set value from the control unit 2. The chamber pressure set value can also be referred to as a chamber pressure value preferred for processing a substrate based on a given recipe. The chamber pressure set value can be specified based on the recipe.

[0051] The communication unit 51 may receive opening degree data regarding the opening degree of the pressure regulating valve 42 from the pressure regulating valve 42. The communication unit 51 may transmit the opening degree data to the control unit 2. The control unit 2 may store the opening degree data received from the communication unit 51 in the memory unit 2a2. The control unit 2 may receive the opening degree data from the pressure regulating valve 42 without going through the pressure valve control device 50. The communication unit 51 may also store the opening degree data received from the pressure regulating valve 42 in the memory unit 56. The opening degree data may be a value of an encoder that controls the opening degree of the pressure regulating valve 42. The control unit 2 may control the operation timing and / or operation speed of the pressure regulating valve 42 based on the opening degree data.

[0052] The pressure information acquiring unit 52 acquires pressure information related to the pressure inside the plasma processing chamber 10. The pressure information may include a measurement value obtained by the pressure sensor 60. The pressure information may include error information related to the error between the chamber pressure setpoint and the measurement value obtained by the pressure sensor 60. The error information may include an error sequence indicating the error between the chamber pressure setpoint and the measured chamber pressure over time. The pressure information acquiring unit 52 may read the chamber pressure setpoint from the storage unit 56 or may receive it from the control unit 2 via the communication unit 51.

[0053] The error sequence, like the manipulated variable sequence, may include multiple elements. Each element of the error sequence may indicate the error between the setpoint of the chamber pressure and the measured chamber pressure at a given time. In one example, an error sequence having K elements may be represented as a K-by-1 vector. Like the manipulated variable sequence, the error sequence may have a length corresponding to one period of the iterative process.

[0054] The update unit 53 updates the control parameters based on the pressure information. The update unit 53 may update the control parameters received from the communication unit 51, or may update the control parameters stored in the storage unit 56. When the control parameters are manipulated variable sequences, the update unit 53 may update the entire manipulated variable sequence, update part of the manipulated variable sequence, add a new element to the manipulated variable sequence, or delete part of the elements of the manipulated variable sequence.

[0055] When the pressure information includes error information, the updating unit 53 may update the control parameters so as to suppress the errors. When the error information includes an error sequence, the updating unit 53 may update the control parameters based on the error sequence so as to suppress the error sequence. In this case, the updating unit 53 may update the control parameters based on an output obtained by applying a low-pass filter to the error sequence. Updating the control parameters so as to suppress the error sequence may involve updating the control parameters so as to reduce some elements of the error sequence, updating the control parameters so as to reduce the average or median of elements included in the error sequence, or updating the control parameters so as to reduce each element of the error sequence compared to before the update.

[0056] The update unit 53 may include a determination unit 55. The determination unit 55 determines whether or not the pressure information satisfies a learning termination condition. If the determination unit 55 determines that the pressure information does not satisfy the learning termination condition, the update unit 53 may update the control parameters based on the pressure information. Furthermore, if the determination unit 55 determines that the pressure information satisfies the learning termination condition, the update of the control parameters by the update unit 53 may be restricted. Restricting the update of the control parameters by the update unit 53 may mean that the update unit 53 does not update the control parameters, or that the update unit 53 updates some of the control parameters (but does not update others).

[0057] In one embodiment, the learning termination condition includes that the convergence rate of the error is equal to or less than a given threshold. The convergence rate may be the time required for the error to fall below a second threshold after exceeding a first threshold. In other words, the update unit 53 may stop updating the control parameters when the control parameters that allow the error to converge sufficiently quickly have been obtained.

[0058] In one embodiment, the learning termination condition includes the magnitude of the error being equal to or less than a given threshold. The magnitude of the error may be the maximum value of the error within a given period. That is, the updating unit 53 may stop updating the control parameters when the control parameters are obtained such that the difference between the set value of the pressure in the chamber and the actual measured value of the pressure in the chamber is kept sufficiently small.

[0059] In one embodiment, the learning termination condition includes the number of times the control parameter has been updated in the iterative process being equal to or greater than a given threshold, i.e., the update unit 53 may stop updating the control parameter when the control parameter has been updated a given number of times.

[0060] The update unit 53 may update the control parameters for each repetition unit in the repetitive process. In one example, when the repetitive process includes processes from a first cycle to a J-th cycle, the update unit 53 updates the control parameters at the start of the first cycle, the start of the second cycle, ..., the start of the J-th cycle.

[0061] When the control parameter is the manipulated variable sequence, the update unit 53 may update the manipulated variable sequence before the start of a cycle next to the cycle in which the pressure information was acquired. In one example, the update unit 53 may update the manipulated variable sequence at the first step of the next cycle, or may update the manipulated variable sequence at the last step of the cycle in which the pressure information was acquired. Updating the manipulated variable sequence before the cycle starts may mean updating the manipulated variable sequence before the cycle starts, or may mean updating the manipulated variable sequence approximately simultaneously with the start of the cycle.

[0062] The opening control unit 54 controls the opening degree of the pressure regulation valve 42 based on the control parameters. The opening control unit 54 may control the opening degree of the pressure regulation valve 42 based on the control parameters received from the update unit 53, or may control the opening degree of the pressure regulation valve 42 based on the control parameters read from the storage unit 56. When the control parameters are a manipulated variable sequence, the opening control unit 54 may sequentially input each element of the manipulated variable sequence to the pressure regulation valve 42. At this time, the opening control unit 54 may input each element of the manipulated variable sequence to the pressure regulation valve 42 at equal time intervals.

[0063] The opening control unit 54 may receive opening data related to the opening of the pressure regulating valve 42 from the pressure regulating valve 42. The opening data may be an encoder value that controls the opening of the pressure regulating valve 42. The opening control unit 54 may control the operation timing and / or operation speed of the pressure regulating valve 42 based on the opening data. The opening control unit 54 may store the opening data received from the pressure regulating valve 42 in the memory unit 56.

[0064] <Example of Substrate Processing Method> In the following description, the process in the first to Jth cycles is an iterative process. That is, "J" is a value indicating the number of repetitions of the iterative process. Each cycle included in the iterative process is divided into a first to Kth step. That is, "K" is a value indicating the number of steps in each cycle. Also, in the following description, the variable j may be an integer between 1 and J, inclusive. The variable k may be an integer between 1 and K, inclusive. In one embodiment, the controller 2 performs a desired process (etching process, film formation process, cleaning process, ashing process, etc.) on the substrate W based on the same recipe in the first to Jth cycles. For example, in each cycle, the controller 2 controls the type and flow rate of gas supplied from the gas supply unit 20 to the plasma processing chamber 10 based on the recipe. Also, for example, in each cycle, the controller 2 controls the power, voltage level, waveform, etc. of the source RF signal and / or bias signal supplied from the power supply 30 to the chamber 10 based on the recipe. Also, for example, the pressure valve control device 50 controls the pressure in the chamber 10 based on the recipe in each cycle. An example of the operation of the pressure valve control device 50 will be described below in the first to fourth embodiments.

[0065] [First embodiment] An example of the operation of the pressure valve control device 50 according to the first embodiment will be described with reference to Fig. 4. Fig. 4 is a flowchart showing an example of the operation of the pressure valve control device 50.

[0066] First, the pressure valve control device 50 acquires a recipe (S100). The recipe may include a set value for the pressure in the chamber. Next, the pressure valve control device 50 acquires initial values ​​for the control parameters (S102). The initial values ​​for the control parameters may be acquired from the memory unit 2a2 of the control unit 2 or the memory unit 56 of the pressure valve control device 50. Next, the pressure valve control device 50 sets the value of the variable j to "1" (S104).

[0067] Next, the pressure valve control device 50 controls the pressure adjustment valve 42 in the jth cycle (here, the value of the variable j is "1", so this is the first cycle) based on the initial values ​​of the control parameters acquired in S102 (S108). This may cause a change in the measured pressure in the chamber.

[0068] Next, the pressure valve control device 50 acquires pressure information for the first cycle (S108). The pressure information may include error information regarding the error between the set value of the pressure in the chamber, which may be included in the recipe acquired in S100, and the measured value of the pressure in the chamber after the change due to the control in S106.

[0069] Next, the pressure valve control device 50 determines whether the pressure information acquired in S108 satisfies the learning end condition (S110).

[0070] If it is determined that the pressure information does not satisfy the learning termination condition (NO in S110), the pressure valve control device 50 updates the control parameters based on the pressure information (S112). Thereafter, the pressure valve control device 50 increments the variable j (S114). Furthermore, the pressure valve control device 50 controls the pressure regulating valve 42 in the jth cycle (here, the value of the variable j is "2," so this is the second cycle) based on the control parameters updated in S112 (S108). The pressure valve control device 50 can typically periodically execute a loop from S106 to S114.

[0071] If it is determined that the pressure information satisfies the learning termination condition (YES in S110), the pressure valve control device 50 determines the control parameters at that time as being capable of sufficiently suppressing the error, and determines the control parameters (S116).

[0072] According to the pressure valve control device 50 of the first embodiment, it is possible to search for and determine control parameters that satisfy the learning end conditions for any recipe.

[0073] Second Embodiment An example of the operation of the pressure valve control device 50 according to the second embodiment will be described with reference to FIGS.

[0074] 5 is a flowchart showing another example of the operation of the pressure valve control device 50. In the flowchart shown in FIG. 5, the operation of the pressure valve control device 50 can be broadly divided into operations corresponding to a first cycle (S202-S212) and operations corresponding to a second cycle and thereafter (S214-S230). The main purpose of the operations corresponding to the first cycle is to obtain the initial value of the error sequence to be used in the operations corresponding to the second cycle. In each of the second cycle and thereafter, the manipulated variable sequence is updated based on the error sequence, and the pressure regulating valve is controlled based on the manipulated variable sequence.

[0075] First, the pressure valve control device 50 acquires a recipe (S200). As in the first embodiment, the recipe may include a set value for the pressure in the chamber.

[0076] Next, the pressure valve control device 50 acquires the initial value of the manipulated variable sequence (S102). The initial value of the manipulated variable sequence can be acquired from the memory unit 2a2 of the control unit 2 or the memory unit 56 of the pressure valve control device 50. In this example, the manipulated variable sequence includes K elements. This is an example of the manipulated variable sequence having a length corresponding to one cycle (i.e., K steps) of the repetitive process. Next, the pressure valve control device 50 sets the value of the variable k to "1" (S204).

[0077] Next, the pressure valve control device 50 controls the pressure regulating valve 42 at the kth step (here, the first step, since the value of variable k is "1") of the first cycle based on the kth element (here, the first element, since the value of variable k is "1") of the initial operation amount sequence obtained in S202 (S206).

[0078] Next, the pressure valve control device 50 obtains the error between the set value of the pressure in the chamber and the measured value of the pressure in the chamber at the kth step of the first cycle (here, the first step because the value of the variable k is "1"), and updates the kth element of the error sequence (here, the first element because the value of the variable k is "1") (S208). In this example, the error sequence includes K elements. This is an example of the error sequence having a length corresponding to one cycle (i.e., K steps) of the iterative process.

[0079] Next, the pressure valve control device 50 determines whether the value of the variable k is equal to "K" (S210). If it is determined that the value of the variable k is not equal to "K" (S210 NO), the pressure valve control device 50 increments the variable k (S212) and controls the pressure regulating valve 42 at the k-th step (here, the second step because the value of the variable k is "2") of the first cycle based on the k-th element (here, the second element because the value of the variable k is "2") of the initial manipulated variable sequence acquired in S202 (S206).

[0080] When the pressure valve control device 50 determines that the value of the variable k is equal to "K" by repeating the loop of S206-S212 (YES in S210), the pressure valve control device 50 sets the value of the variable j to "2" (S214). In other words, when it is determined that the last step of the first cycle has been completed, the pressure valve control device 50 starts the second cycle.

[0081] Next, the pressure valve control device 50 sets the value of the variable k to "1" again (S216). Next, the pressure valve control device 50 updates the manipulated variable sequence based on the error sequence obtained in the most recent S208 (S218). Next, the pressure valve control device 50 controls the pressure regulating valve in the kth step (here, the first step because the value of the variable k is "1") of the jth cycle (here, the second cycle because the value of the variable j is "2") based on the kth element (here, the first element because the value of the variable k is "1") of the updated manipulated variable sequence (S220). Note that in S218, the manipulated variable sequence is updated before control of the pressure regulating valve 42 in the second cycle is started. This is an example of updating the manipulated variable sequence before the start of the next cycle.

[0082] Next, the pressure valve control device 50 obtains the error between the set value of the pressure in the chamber and the measured value of the pressure in the chamber at the kth step (here, the first step because the value of the variable k is "1") of the jth cycle (here, the second cycle because the value of the variable j is "2"), and updates the kth element (here, the first element because the value of the variable k is "1") of the error sequence (S222).

[0083] Next, the pressure valve control device 50 determines whether the value of the variable k is equal to "K" (S224). If it is determined that the value of the variable k is not equal to "K" (S224 NO), the pressure valve control device 50 increments the variable k (S226) and controls the pressure regulating valve 42 at the kth step (here, the second step because the value of the variable k is "2") of the jth cycle (here, the second cycle because the value of the variable j is "2") based on the kth element (here, the second element because the value of the variable k is "2") of the manipulated variable sequence (S220).

[0084] When the pressure valve control device 50 determines that the value of variable k is equal to "K" by repeating the loop of S220-S226 (YES in S224), the pressure valve control device 50 determines whether the value of variable j is equal to "J" (S228). When it determines that the value of variable j is not equal to "J" (NO in S228), the pressure valve control device 50 increments variable j (S230) and sets the value of variable k to "1" again (S216). In other words, when it is determined that the repetitive process has not been completed to the end, the pressure valve control device 50 starts the operation corresponding to the next cycle.

[0085] When the pressure valve control device 50 repeats the loop of S216-S230 and determines that the value of the variable j is equal to "J" (YES in S228), the pressure valve control device 50 may end its operation. In other words, when it is determined that the final cycle of the repetitive process has been completed, the pressure valve control device 50 may end its operation.

[0086] FIG. 6 is an example of a control block diagram of a pressure valve control device 50 according to the second embodiment. In FIG. 6, first, the manipulated variable u k is input from the memory to the pressure regulating valve 42. Next, an error e is output from the block corresponding to the pressure information acquisition unit 52 based on the output y from the pressure regulating valve 42 and the set value r of the pressure in the chamber. Note that the output y may include the measured value of the pressure in the chamber. Next, the error e is input to the learning filter L of the block corresponding to the update unit 53. The output from the learning filter L is calculated based on the manipulated variable u input from the memory. k The sum is passed through a low-pass filter Q to generate the next manipulated variable u k+1 is entered into memory as

[0087] Updating the manipulated variable sequence in each cycle of the repetitive process as in the second embodiment can also be called ILC (Iterative Learning Control).

[0088] [Third Embodiment] An example of the operation of the pressure valve control device 50 according to the third embodiment will be described with reference to Fig. 7. In the above-described second embodiment, an example was described in which the pressure valve control device 50 controls the pressure regulating valve 42 based on the initial values ​​of the manipulated variable sequence in the first cycle, but in the third embodiment, a method will be described in which the initial values ​​of the manipulated variable sequence are not used in the first cycle.

[0089] First, the pressure valve control device 50 acquires an initial value of the aperture of the pressure regulating valve 42 (S300). Next, the pressure valve control device 50 sets the variable k to "1" (S302). Next, the pressure valve control device 50 controls the pressure regulating valve 42 in the kth step of the first cycle (here, the first step since the variable k is "1") based on the initial value of the aperture of the pressure regulating valve 42 acquired in S300 (S304). Next, the pressure valve control device 50 acquires an error in the kth step (here, the first step since the variable k is "1") and updates the kth element of the error sequence (here, the first element since the variable k is "1") (S306). Next, the pressure valve control device 50 updates the aperture of the pressure regulating valve 42 based on the error (S308).

[0090] Next, the pressure valve control device 50 determines whether the value of the variable k is equal to "K" (S310). If it is determined that the value of the variable k is not equal to "K" (NO in S310), the pressure valve control device 50 increments the variable k (S312) and controls the pressure regulating valve 42 in the k-th step of the first cycle (here, the value of the variable k is "2", so this is the second step) based on the opening degree of the pressure regulating valve 42 updated in S308 (S304).

[0091] When the pressure valve control device 50 repeats the loop of S304-S312 and determines that the value of the variable k is equal to "K" (YES in S310), the pressure valve control device 50 can start the operation corresponding to the second cycle or later.

[0092] The operation corresponding to the first cycle described with reference to Fig. 5 may be replaced by the operation corresponding to the first cycle described with reference to Fig. 7. The operation corresponding to the first cycle described with reference to Fig. 5 is an operation based on a feedforward (FF) concept in that the pressure regulating valve 42 is controlled in accordance with a predetermined manipulated variable sequence. On the other hand, the operation corresponding to the first cycle described with reference to Fig. 7 is an operation based on a feedback (FB) concept in that the opening of the pressure regulating valve 42 is sequentially updated based on the error in each step. By using either of these methods, the pressure valve control device 50 can obtain the initial value of the error sequence used in the operation corresponding to the second cycle.

[0093] [Fourth Embodiment] An example of the operation of a pressure valve control device 50 according to a fourth embodiment will be described with reference to Figures 8 and 9. Figure 8 is a diagram showing an example of simulation results of the changes in the pressure in the chamber, the pressure adjustment valve opening, the DC voltage applied to the chamber, and the gas flow rate supplied to the chamber from the first cycle to the tenth cycle. The changes in the DC voltage and the gas flow rate are the same in each of the first cycle to the tenth cycle. The first cycle to the tenth cycle are an example of a repetitive process that is periodically repeated on a substrate based on the same recipe.

[0094] In Fig. 8, the dotted lines indicate the changes in the pressure inside the chamber and the pressure regulation valve aperture when the pressure regulation valve 42 is controlled by feedback control. Also, in Fig. 8, the solid lines indicate the changes in the pressure inside the chamber and the pressure regulation valve aperture when the pressure regulation valve 42 is controlled by ILC (see the second and third embodiments). Comparing the dotted and solid lines, it can be seen that in the case of feedback control, the fluctuations in the pressure inside the chamber do not converge until the tenth cycle, whereas in the case of ILC, the fluctuations have already nearly converged by the third cycle.

[0095] Fig. 9 is an enlarged view of area Ar in Fig. 8. At the start of the first cycle, the pressure valve control device 50 acquires the initial value of the manipulated variable sequence (see S202 in Fig. 5). The pressure valve control device 50 controls the opening degree of the pressure regulating valve 42 during the period corresponding to the first cycle based on the initial value of the manipulated variable sequence (see S204-S212 in Fig. 5).

[0096] At the start of the second cycle, the pressure valve control device 50 updates the manipulated variable sequence based on the error sequence acquired during the period corresponding to the first cycle (see S218 in FIG. 5). The pressure valve control device 50 controls the opening degree of the pressure regulating valve 42 during the period corresponding to the second cycle based on the updated manipulated variable sequence (see S220-S226 in FIG. 5). The same applies to the third cycle.

[0097] In this way, when a cycle starts, the pressure valve control device 50 can determine a manipulated variable sequence for controlling the aperture of the pressure regulating valve 42 during a period corresponding to the cycle. This allows the pressure valve control device 50 to respond to pressure fluctuations in a "predictive" manner, compared to when the aperture of the pressure regulating valve 42 is determined sequentially using feedback control. For example, in FIG. 9 , the maximum value Pt1 of the pressure regulating valve aperture (solid line) in the feedback control in ILC occurs earlier than the maximum value Pt2 of the pressure regulating valve aperture (dotted line) in the feedback control. This indicates that ILC can predict pressure fluctuations in a repetitive process and suppress those fluctuations in a preemptive manner.

[0098] [Modification] The pressure valve control device 50 may be configured to perform both ILC and FB control. Fig. 10 shows an example of a control block diagram of the pressure valve control device 50 in this case. In the control block diagram of Fig. 10, an FB controller is added to the control block diagram of Fig. 6. The FB controller receives an error e as an input, and calculates an FB manipulated variable u k fb The FB control input u k fb is the ILC operation amount u k ILC and can be input to the pressure regulating valve 42 as the manipulated variable u.

[0099] In the first embodiment, an example of the operation for determining control parameters that satisfy the learning termination condition was described. In the second embodiment, an example of repeatedly updating the manipulated variable sequence from the first cycle to the Jth cycle was described. The plasma processing apparatus 1 may determine control parameters (or manipulated variable sequence) by applying the method exemplified in the first embodiment (or the second embodiment) to at least one first substrate, and process at least one second substrate using the determined control parameters (or manipulated variable sequence). Here, at least one first substrate may be a test substrate. At least one second substrate may be a product substrate. That is, the plasma processing apparatus 1 may determine suitable control parameters (or manipulated variable sequence) using a test substrate, and then process the product substrate using the control parameters (or manipulated variable sequence). Note that determining the manipulated variable sequence may involve repeatedly executing the processes of S214-S230 in FIG. 5 until a manipulated variable sequence that satisfies a given learning termination condition is obtained, or may involve updating the manipulated variable sequence a given number of times.

[0100] In this case, the plasma processing apparatus 1 may be configured to at least temporarily record the control parameters (or manipulated variable sequence) in a database in the storage unit 56 and read them out as appropriate. Specifically, the plasma processing apparatus 1 determines the control parameters (or manipulated variable sequence) by applying the method exemplified in the first embodiment (or the second embodiment) to at least one first substrate. The plasma processing apparatus 1 may then record the determined control parameters (or manipulated variable sequence) in the database in the storage unit 56. Thereafter, the plasma processing apparatus 1 may read the control parameters (or manipulated variable sequence) from the database and process at least one second substrate. The database may store the recorded information long-term.

[0101] The at least one second substrate may be processed consecutively from the at least one first substrate. For example, when the plasma processing apparatus 1 processes a plurality of substrates consecutively, the first several of the plurality of substrates may be the first substrates, and the remaining substrates may be the second substrates. Furthermore, the at least one second substrate may be processed at a time interval from the at least one first substrate. For example, the plasma processing apparatus 1 may process the first substrate at a first time point, and process the second substrate at a second time point after a given time has elapsed (e.g., several hours) from the first time point.

[0102] In the above embodiment, the term "jth cycle" is used to mean the jth cycle counting from the first cycle in the repeating process, but this is not limited to the scope of the claims. For example, the "first cycle" and the "second cycle" in the claims may respectively mean the fifth cycle and the tenth cycle counting from the first cycle in the repeating process. The "first cycle" and the "second cycle" in the claims may respectively be read as, for example, a "cycle" and an "other cycle."

[0103] Embodiments of the present disclosure further include the following aspects.

[0104] (Supplementary Note 1) A substrate processing apparatus comprising: a chamber; a substrate support unit disposed within the chamber; a pressure regulating valve configured to adjust the pressure within the chamber; a gas supply unit configured to supply gas to the chamber; and a control unit configured to execute a repetitive process that is periodically repeated on a substrate based on the same recipe, wherein the control unit is configured to perform, in each cycle of the repetitive process, (a) supplying gas from the gas supply unit to the chamber; (b) controlling the pressure regulating valve based on a control parameter related to an opening degree of the pressure regulating valve; (c) acquiring pressure information related to the pressure within the chamber in (b); and (d) updating the control parameter based on the pressure information.

[0105] (Supplementary Note 2) The substrate processing apparatus according to Supplementary Note 1, wherein the control parameters include an operation amount sequence that indicates an operation amount of the pressure adjustment valve over time.

[0106] (Supplementary Note 3) The substrate processing apparatus according to Supplementary Note 2, wherein the manipulated variable sequence has a length corresponding to one cycle of the repetitive process.

[0107] (Supplementary Note 4) The substrate processing apparatus according to Supplementary Note 2 or 3, wherein in (d), the control unit updates the manipulated variable sequence before a next cycle starts.

[0108] (Supplementary Note 5) A substrate processing apparatus according to any one of Supplementary Notes 1 to 4, wherein the pressure information includes error information relating to an error between a set value of the pressure in the chamber and a measured value of the pressure in the chamber, and the control unit, in (d), updates the control parameters based on the error information so as to suppress the error.

[0109] (Supplementary Note 6) The substrate processing apparatus according to Supplementary Note 5, wherein the error information includes an error sequence indicating a value of the error over time, and the control unit updates the control parameters based on the error sequence in (d) so that the error sequence is suppressed.

[0110] (Supplementary Note 7) The substrate processing apparatus according to Supplementary note 6, wherein in (d), the control unit updates the control parameters based on an output obtained by applying a low-pass filter to the error sequence.

[0111] (Appendix 8) The control unit further executes (e) determining whether the pressure information satisfies a learning termination condition, and if it is determined in (e) that the pressure information does not satisfy the learning termination condition, it updates the control parameters based on the pressure information in (d), and if it is determined in (e) that the pressure information satisfies the learning termination condition, the updating of the control parameters in (d) is restricted. (Appendix 8) A substrate processing apparatus according to any one of Appendices 5 to 7.

[0112] (Supplementary Note 9) The substrate processing apparatus according to Supplementary Note 8, wherein the learning termination condition includes a condition that the convergence rate of the error is equal to or less than a given threshold value.

[0113] (Supplementary Note 10) The substrate processing apparatus according to Supplementary Note 8 or 9, wherein the learning termination condition includes that the magnitude of the error is equal to or less than a given threshold value.

[0114] (Supplementary Note 11) The substrate processing apparatus according to any one of Supplementary Notes 8 to 10, wherein the learning termination condition includes a condition that the number of times the control parameter is updated in the repetitive process is equal to or less than a given threshold value.

[0115] (Supplementary Note 12) The substrate processing apparatus according to any one of Supplementary Notes 1 to 11, wherein the repeated processes are processes for the same substrate.

[0116] (Supplementary Note 13) A substrate processing method using a substrate processing apparatus, the substrate processing apparatus comprising: a chamber; a substrate support unit disposed within the chamber; a pressure regulating valve configured to adjust the pressure within the chamber; and a gas supply unit configured to supply gas to the chamber, the method including performing a repetitive process that is periodically repeated on a substrate based on the same recipe, each cycle of the repetitive process including: (a) a step of supplying gas from the gas supply unit to the chamber; (b) a step of controlling the pressure regulating valve based on a control parameter related to an opening degree of the pressure regulating valve; (c) a step of acquiring pressure information related to the pressure within the chamber in (b); and (d) a step of updating the control parameter based on the pressure information.

[0117] (Supplementary Note 14) The substrate processing method according to Supplementary Note 13, wherein the control parameters include an operation amount sequence indicating an operation amount of the pressure adjustment valve over time.

[0118] (Supplementary Note 15) A program causing a computer of a substrate processing apparatus to execute a repetitive process that is periodically repeated on a substrate based on the same recipe, the substrate processing apparatus comprising: a chamber; a substrate support unit disposed within the chamber; a pressure regulating valve configured to be able to adjust the pressure within the chamber; and a gas supply unit configured to supply gas to the chamber, wherein each cycle of the repetitive process includes: (a) supplying gas from the gas supply unit to the chamber; (b) controlling the pressure regulating valve based on a control parameter related to an opening degree of the pressure regulating valve; (c) acquiring pressure information related to the pressure within the chamber in (b); and (d) updating the control parameter based on the pressure information.

[0119] (Supplementary Note 16) The program according to Supplementary Note 15, wherein the control parameters include an operation amount sequence indicating an operation amount of the pressure regulating valve over time.

[0120] 1... plasma processing apparatus, 2... control unit, 2a... computer, 11... substrate support unit, 20... gas supply unit, 30... power supply, 42... pressure regulating valve, 50... pressure valve control device, 51... communication unit, 52... pressure information acquisition unit, 53... update unit, 54... opening control unit, 55... determination unit, 60... pressure sensor, 100... pressure regulation system, L... learning filter, Q... low-pass filter

Claims

1. A substrate processing apparatus comprising: a chamber; a substrate support unit disposed within the chamber; a pressure regulating valve configured to adjust the pressure within the chamber; a gas supply unit configured to supply gas to the chamber; and a control unit configured to perform a repetitive process that is periodically repeated on a substrate based on the same recipe, wherein the control unit is configured to perform, in each cycle of the repetitive process, the following: (a) supplying gas from the gas supply unit to the chamber; (b) controlling the pressure regulating valve based on a control parameter related to the opening degree of the pressure regulating valve; (c) acquiring pressure information related to the pressure within the chamber in (b); and (d) updating the control parameter based on the pressure information.

2. The substrate processing apparatus according to claim 1, wherein the control parameters include an operation amount sequence indicating an operation amount of the pressure regulating valve over time.

3. The substrate processing apparatus according to claim 2, wherein the sequence of manipulated variables has a length corresponding to one cycle of the repetitive process.

4. The substrate processing apparatus according to claim 2, wherein in (d), the control unit updates the manipulated variable sequence before the next cycle starts.

5. The substrate processing apparatus of claim 1, wherein the pressure information includes error information regarding the error between the set value of the pressure in the chamber and the measured value of the pressure in the chamber, and the control unit updates the control parameters in (d) based on the error information so as to suppress the error.

6. The substrate processing apparatus of claim 5, wherein the error information includes an error sequence indicating the value of the error over time, and the control unit updates the control parameters based on the error sequence in (d) so that the error sequence is suppressed.

7. The substrate processing apparatus according to claim 6, wherein in (d), the control unit updates the control parameters based on an output obtained by applying a low-pass filter to the error sequence.

8. The substrate processing apparatus of claim 5, wherein the control unit further executes (e) determining whether the pressure information satisfies a learning termination condition, and if it is determined in (e) that the pressure information does not satisfy the learning termination condition, it updates the control parameters based on the pressure information in (d), and if it is determined in (e) that the pressure information satisfies the learning termination condition, it restricts the update of the control parameters in (d).

9. The substrate processing apparatus according to claim 8, wherein the learning termination condition includes that the convergence rate of the error is equal to or less than a given threshold value.

10. The substrate processing apparatus according to claim 8, wherein the learning termination condition includes the magnitude of the error being equal to or less than a given threshold value.

11. The substrate processing apparatus according to claim 8, wherein the learning termination condition includes the number of times the control parameter has been updated in the repetitive process being equal to or less than a given threshold value.

12. The substrate processing apparatus according to claim 1, wherein the repeated processes are performed on the same substrate.

13. A substrate processing method using a substrate processing apparatus, the substrate processing apparatus comprising: a chamber; a substrate support unit disposed within the chamber; a pressure regulating valve configured to adjust the pressure within the chamber; and a gas supply unit configured to supply gas to the chamber, the method including performing a repetitive process that is periodically repeated on a substrate based on the same recipe, each cycle of the repetitive process including: (a) a step of supplying gas from the gas supply unit to the chamber; (b) a step of controlling the pressure regulating valve based on a control parameter related to the opening degree of the pressure regulating valve; (c) a step of acquiring pressure information related to the pressure within the chamber in (b); and (d) a step of updating the control parameter based on the pressure information.

14. The substrate processing method according to claim 13, wherein the control parameters include an operation amount sequence that indicates an operation amount of the pressure regulating valve over time.

15. A program that causes a computer of a substrate processing apparatus to execute a repetitive process that is periodically repeated on a substrate based on the same recipe, wherein the substrate processing apparatus comprises: a chamber; a substrate support unit disposed within the chamber; a pressure regulating valve configured to adjust the pressure within the chamber; and a gas supply unit configured to supply gas to the chamber, and each cycle of the repetitive process includes: (a) supplying gas from the gas supply unit to the chamber; (b) controlling the pressure regulating valve based on a control parameter related to the opening degree of the pressure regulating valve; (c) acquiring pressure information related to the pressure within the chamber in (b); and (d) updating the control parameter based on the pressure information.

16. The program according to claim 15, wherein the control parameters include an operation amount sequence indicating an operation amount of the pressure regulating valve over time.

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