Gas supply system, program, and gas supply method

Abstract

The present invention provides a gas supply system, method, and program for efficiently increasing the gas pressure within a gas pipeline. [Solution] A gas supply system S alternately repeats a first step of supplying a first gas through a first gas pipe 51c to a gas diffusion chamber 13b into a plasma processing chamber 10 and plasma processing an object W to be processed, and a second step of supplying a second gas through a second gas pipe 52c to a gas diffusion chamber into a plasma processing chamber and plasma processing an object to be processed, and includes a first valve 51d for controlling communication between the first gas pipe and the gas diffusion chamber, a second valve 52d for controlling communication between the second gas pipe and the gas diffusion chamber, a first gas supply mechanism 51 for raising the pressure of the first gas in the first gas pipe to a first pressure before the first step, a second gas supply mechanism 52 for raising the pressure of the second gas in the second gas pipe to a second pressure before the second step, and a control unit 2 for controlling the first gas supply mechanism and the second gas supply mechanism.

Description

Technical Field

[0001] The present disclosure relates to a gas supply system, a program, and a gas supply method.

Background Art

[0002] As the integration of semiconductor devices progresses not only in the horizontal direction but also in the vertical direction, the aspect ratio of patterns formed in the manufacturing process of semiconductor devices has been increasing. For example, in the manufacture of 3D NAND, channel holes are formed in the direction penetrating a number of metal wiring layers. In the case of forming a 64-layer memory cell, the aspect ratio of the channel holes becomes 45.

[0003] Various methods have been proposed for forming high-aspect-ratio patterns with high precision. For example, a method has been proposed in which etching and film formation are repeatedly performed in an opening formed in a dielectric material of a substrate to suppress lateral etching. Further, a method has been proposed in which a protective film for preventing lateral etching of a dielectric layer is formed by combining etching and film formation (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides a gas supply system and the like that can efficiently increase the pressure of gas in a gas pipe before a step of plasma-treating a workpiece.

Means for Solving the Problems

[0006] A gas supply system according to one embodiment of the present disclosure is a gas supply system for a semiconductor manufacturing apparatus that alternately repeats a first step of supplying a first gas into a chamber through a first gas pipe and passing it through a diffusion chamber to perform plasma treatment on an object to be processed, and a second step of supplying a second gas into the chamber through a second gas pipe and passing it through the diffusion chamber to perform plasma treatment on an object to be processed, and includes a first valve for controlling the communication between the first gas pipe and the diffusion chamber by opening and closing, a second valve for controlling the communication between the second gas pipe and the diffusion chamber by opening and closing, a first gas supply mechanism that closes the first valve before the first step and raises the pressure of the first gas in the first gas pipe to a first pressure with the first gas, a second gas supply mechanism that closes the second valve before the second step and raises the pressure of the second gas in the second gas pipe to a second pressure with the second gas, and a control unit for controlling the first gas supply mechanism and the second gas supply mechanism. [Effects of the Invention]

[0007] According to this disclosure, by efficiently increasing the gas pressure in the gas piping before the plasma treatment process of the workpiece, it is possible to achieve faster gas exchange than before without unnecessary gas exhaust. [Brief explanation of the drawing]

[0008] [Figure 1] This figure illustrates an example configuration of a capacitively coupled plasma processing apparatus according to Embodiment 1. [Figure 2] This is an explanatory diagram showing an example of the time course of gas pressure and gas flow rate in a gas pipeline. [Figure 3] This is an explanatory diagram illustrating an example of shortening the gas exchange time in the chamber (processing room) by increasing the pressure in the gas piping. [Figure 4] This is an explanatory diagram showing an example of a timing chart for valve operation, etc. [Figure 5] This is an explanatory diagram regarding the generation process of a learning model (pressure estimation model). [Figure 6] This is a flowchart illustrating the processing steps of the control unit. [Figure 7] This figure illustrates an example configuration of a capacitively coupled plasma processing apparatus according to Embodiment 2 (multiple diffusion chambers). [Figure 8] This figure illustrates an example configuration of a capacitively coupled plasma processing apparatus according to Embodiment 3 (third gas). [Figure 9] This is an explanatory diagram showing an example of a timing chart for valve operation, etc. (continuous supply of a third gas). [Figure 10] This is an explanatory diagram showing an example of a timing chart for valve operation, etc. (intermittent supply of a third gas). [Modes for carrying out the invention]

[0009] (Embodiment 1) The following describes an example of the configuration of a plasma processing system. The plasma processing system includes a gas supply system S that supplies gas to the plasma processing apparatus 1 (semiconductor manufacturing apparatus) included in the plasma processing system. Figure 1 is a diagram illustrating an example of the configuration of a capacitively coupled plasma processing apparatus 1 according to Embodiment 1. In this embodiment, a capacitively coupled plasma processing apparatus 1 is described as an example of a semiconductor manufacturing apparatus, but it is not limited to this, and the semiconductor manufacturing apparatus may be an inductively coupled plasma processing apparatus 1.

[0010] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a control unit 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit, a power supply system 30, and an exhaust system 40. Furthermore, the plasma processing apparatus 1 includes a gas diversion mechanism 6 positioned between the gas supply unit and the plasma processing chamber 10. The plasma processing apparatus 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is positioned inside the plasma processing chamber 10. The shower head 13 is positioned above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space defined by the shower head 13, the side walls of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port 13a for supplying at least one processing gas to the plasma processing space, and at least one gas outlet for discharging gas from the plasma processing space. The plasma processing chamber 10 is grounded. The shower head 13 and the substrate support portion 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0011] The substrate support portion 11 includes a main body and a ring assembly. The main body has a central region for supporting the workpiece W (substrate) and an annular region for supporting the ring assembly. A wafer is an example of the workpiece W (substrate). In a plan view, the annular region of the main body surrounds the central region of the main body. The workpiece W (substrate) is placed on the central region of the main body, and the ring assembly is placed on the annular region of the main body so as to surround the workpiece W (substrate) on the central region of the main body. Therefore, the central region is also called the substrate support surface for supporting the workpiece W (substrate), and the annular region is also called the ring support surface for supporting the ring assembly.

[0012] In one embodiment, the main body includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base can function as a lower electrode. The electrostatic chuck is placed on the base. The electrostatic chuck includes a ceramic member and an electrostatic chuck electrode placed within the ceramic member. The electrostatic chuck electrode is also called a clamping electrode. In one embodiment, the electrostatic chuck electrode is electrically connected or coupled to a chuck power supply. The chuck power supply may be a DC power supply or an AC power supply. The ceramic member has a central region. In one embodiment, the ceramic member also has an annular region. Other members surrounding the electrostatic chuck, such as an annular electrostatic chuck or an annular insulating member, may also have an annular region. In this case, the ring assembly may be placed on the annular electrostatic chuck or the annular insulating member, or on both the electrostatic chuck and the annular insulating member. Furthermore, at least one bias electrode, electrically connected or coupled to a power supply 31 and / or power supply 32 described later, may be placed within the ceramic member. In this case, at least one bias electrode functions as a lower electrode. Furthermore, the conductive member of the base and the bias electrode in the ceramic member may function as multiple lower electrodes. In one embodiment, the first voltage generation unit 32a, which functions as a voltage pulse generation unit described later, is electrically connected or coupled to the bias electrode in the ceramic member, and the first RF generation unit 31a, described later, is electrically connected or coupled to the conductive member of the base. Also, an electrostatic chuck electrode may function as a lower electrode. Therefore, the substrate support unit 11 includes at least one lower electrode.

[0013] The ring assembly 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 covering ring. The edge rings are formed of a conductive or insulating material, and the covering rings are formed of an insulating material.

[0014] Further, the substrate support portion 11 may include a temperature control module configured to adjust at least one of the electrostatic chuck, the ring assembly, and the substrate to a target temperature. The temperature control 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. In one embodiment, the flow path is formed in the base, and one or more heaters are disposed in the ceramic member of the electrostatic chuck. Further, the substrate support portion 11 may include a heat transfer gas supply portion configured to supply a heat transfer gas to a gap between the back surface and the central region of the object to be processed W (substrate).

[0015] The shower head 13 is configured to introduce at least one process gas from the gas supply portion into the plasma processing space. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas introduction ports 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 from the plurality of gas introduction ports 13c. Further, the shower head 13 includes at least one upper electrode. The gas introduction portion may include, in addition to the shower head 13, one or more side gas injection portions (SGI; Side Gas Injector) attached to one or more openings formed in the side wall.

[0016] The gas supply portion may include at least one gas source and at least one flow rate controller. In one embodiment, the gas supply portion is configured to supply at least one process gas from the corresponding gas source to the shower head 13 through the corresponding flow rate controller. Each flow rate controller may include, for example, a mass flow controller or a pressure control type flow rate controller. Further, the gas supply portion may include one or more flow rate modulation devices that modulate or pulse the flow rate of at least one process gas.

[0017] In the illustration of this embodiment, the gas supply unit includes a first gas supply mechanism 51 and a second gas supply mechanism 52, and functions as a gas supply system S of the plasma processing apparatus 1 (semiconductor manufacturing apparatus). The first gas supply mechanism 51 supplies, for example, a source gas to the plasma processing chamber 10. The second gas supply mechanism 52 supplies, for example, a reaction gas to the plasma processing chamber 10.

[0018] The first gas supply mechanism 51 includes a first gas source 51a, a first flow controller 51b (MFC), a first gas pipe 51c, a first valve 51d, and a first pressure gauge 51e. The first gas source 51a, the first flow controller 51b (MFC), and the first valve 51d are connected in this order via the first gas pipe 51c. For example, a source gas is stored in the first gas source 51a. The first flow controller 51b (MFC) controls the flow rate of the first gas flowing out from the first gas source 51a according to a control signal from the control unit 2.

[0019] The first valve 51d is opened and closed according to a control signal from the control unit 2. In a state where the first valve 51d is closed, by increasing the flow rate of the first gas flowing out from the first gas source 51a by the first flow controller 51b (MFC), the pressure of the first gas pipe 51c upstream (front stage) of the first valve 51d can be increased. The first pressure gauge 51e periodically or constantly measures the pressure between the first flow controller 51b (MFC) and the first valve 51d in the first gas pipe 51c, and periodically outputs the measured pressure value to the control unit 2.

[0020] The control unit 2 raises the pressure in the first gas piping 51c upstream of the first valve 51d to a first pressure by controlling the flow rate (starting supply) from the first gas source 51a using the first flow controller 51b, in accordance with the pressure value output from the first pressure gauge 51e. After raising the pressure to the first pressure, the control unit 2 can maintain the first pressure by stopping the supply from the first gas source 51a using the first flow controller 51b. As will be described in detail later, when the pressure in the first gas piping 51c is raised to the first pressure, the control unit 2 can open the first valve 51d to increase the flow velocity of the first gas flowing into the plasma processing chamber 10, thereby enabling the gas exchange from the second gas to the first gas in the plasma processing chamber 10 to be completed quickly and in a short amount of time.

[0021] The first gas supply mechanism 51 may further include one or more temperature sensors that detect the ambient temperature around the first gas pipe 51c or the temperature of the first gas pipe 51c. The temperature sensors may output the detected temperature to the control unit 2, and the control unit 2 may acquire the temperature from the temperature sensors as the ambient temperature of the pipe. For example, the temperature sensors may be placed before and after the first valve 51d in the first gas pipe 51c, and detect the ambient temperature of the first gas pipe 51c before the first valve 51d (pre-valve first gas pipe 51c) and the ambient temperature of the first gas pipe 51c after the first valve 51d (post-valve first gas pipe 51c), and output these to the control unit 2.

[0022] The second gas supply mechanism 52 includes a second gas source 52a, a second flow controller 52b (MFC), a second gas piping 52c, a second valve 52d, and a second pressure gauge 52e. The second gas source 52a, the second flow controller 52b (MFC), and the second valve 52d are connected in this order via the second gas piping 52c. The second gas source 52a stores, for example, a reaction gas. The second flow controller 52b (MFC) controls the flow rate of the second gas flowing out of the second gas source 52a in response to a control signal from the control unit 2.

[0023] The second valve 52d is opened and closed in response to a control signal from the control unit 2. When the second valve 52d is closed, the second flow controller 52b (MFC) can increase the flow rate of the second gas flowing out of the second gas source 52a, thereby increasing the pressure in the second gas piping 52c upstream of the second valve 52d. The second pressure gauge 52e periodically or steadily measures the pressure between the second flow controller 52b (MFC) and the second valve 52d in the second gas piping 52c, and periodically outputs the measured pressure value to the control unit 2.

[0024] The control unit 2 raises the pressure in the second gas piping 52c upstream of the second valve 52d to the second pressure by controlling the flow rate (starting supply) from the second gas source 52a using the second flow controller 52b, in accordance with the pressure value output from the second pressure gauge 52e. After raising the pressure to the second pressure, the control unit 2 can maintain the second pressure by stopping the supply from the second gas source 52a using the second flow controller 52b. As will be described in detail later, when the pressure in the second gas piping 52c is raised to the second pressure, the control unit 2 can open the second valve 52d to improve the flow velocity of the second gas flowing into the plasma processing chamber 10, thereby enabling the gas exchange from the first gas to the second gas in the plasma processing chamber 10 to be completed quickly and in a short amount of time.

[0025] The second gas supply mechanism 52 may further include one or more temperature sensors that detect the ambient temperature around the second gas pipe 52c or the temperature of the second gas pipe 52c. The temperature sensors may output the detected temperature to the control unit 2, and the control unit 2 may acquire the temperature from the temperature sensors as the ambient temperature of the pipe. For example, the temperature sensors may be placed before and after the second valve 52d in the second gas pipe 52c, and detect the ambient temperature of the second gas pipe 52c before the second valve 52d (pre-valve second gas pipe 52c) and the ambient temperature of the second gas pipe 52c after the second valve 52d (post-valve second gas pipe 52c), and output these to the control unit 2.

[0026] In this embodiment, the first gas supply mechanism 51 and the second gas supply mechanism 52 each include separate valves (first valve 51d and second valve 52d), but are not limited to this. The first valve 51d and the second valve 52d may, for example, be configured as three-way valves, with the two inlet ports of the three-way valve connected to the first gas piping 51c and the second gas piping 52c, and the outlet port connected to the gas diversion mechanism 6. In this case, the control unit 2 alternately switches the opening and closing of the two inlet ports of the three-way valve to alternately repeat the process of supplying the first gas to the plasma processing chamber 10 through the first gas piping 51c and the process of supplying the second gas to the plasma processing chamber 10 through the second gas piping 52c.

[0027] The gas diversion mechanism 6 includes one or more diversion channels 61 and one or more diversion valves 62, and is interposed between the gas supply unit and the plasma processing chamber 10. In this embodiment, the gas diversion mechanism 6 includes two diversion channels 61 and two diversion valves 62, each of which is located in one of the two diversion channels 61. The diversion valves 62 are electrically operated valves whose opening degree is controlled by, for example, a stepping motor, and are opened and closed based on a signal from the control unit 2, and when open, the opening degree is controlled.

[0028] Each of the diversion channels 61 is divided by a diversion valve 62 into an upstream diversion channel 61 located upstream of the diversion valve 62 and a downstream diversion channel 61 located downstream of the diversion valve 62. Each of the two downstream diversion channels 61 is connected to each of the two gas supply ports 13a formed in the shower head 13. The two upstream diversion channels 61 are joined upstream, and the joined channels are connected to the first gas pipe 51c and the second gas pipe 52c. The control unit 2 may control these diversion valves 62 to be normally open, or it may control the opening degree of the diversion valves 62 so that the diversion ratio, which is the ratio of the gas flow rates through each of the multiple diversion channels 61, becomes the target diversion ratio according to the processing recipe.

[0029] The power supply system 30 includes a power supply 31 that is electrically connected to or coupled to the plasma processing chamber 10. In one embodiment, the power supply 31 is electrically connected to or coupled to the plasma processing chamber 10 via at least one impedance matcher. The impedance matcher may be a mechanically controlled or electronically controlled matcher. The power supply 31 is configured to supply at least one RF (Radio Frequency) signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates plasma from at least one processing gas supplied to the plasma processing space. Thus, the power supply 31 can function as at least part of a plasma generation unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential is generated on the workpiece W (substrate), and ionic components in the formed plasma can be drawn into the workpiece W (substrate).

[0030] The power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is electrically connected or coupled to at least one lower electrode and / or at least one upper electrode and is configured to generate a source RF signal (source RF power) to generate plasma in the plasma processing space. In one embodiment, the first RF generation unit 31a is electrically connected or coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matcher. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. One or more generated source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0031] The second RF generation unit 31b is electrically connected to or coupled to at least one lower electrode and is configured to generate a bias RF signal (bias RF power). In one embodiment, the second RF generation unit 31b is electrically connected to or coupled to at least one lower electrode via at least one impedance matcher. If the first RF generation unit 31a is electrically connected to or coupled to a lower electrode, the second RF generation unit 31b may be electrically connected to or coupled to the same lower electrode, or it may be electrically connected to or coupled to a different lower electrode. 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 lower frequency than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0032] The power supply system 30 may also include a power supply 32 that is electrically connected to or coupled to the plasma processing chamber 10. The power supply 32 includes a first voltage generation unit 32a and a second voltage generation unit 32b. In one embodiment, the first voltage generation unit 32a is electrically connected to or coupled to at least one lower electrode and configured to generate a first voltage signal. The generated first voltage signal is applied to at least one lower electrode. In one embodiment, the second voltage generation unit 32b is electrically connected to or coupled to at least one upper electrode and configured to generate a second voltage signal. The generated second voltage signal is applied to at least one upper electrode.

[0033] In various embodiments, the first and / or second voltage signals may be pulsed. In this case, the first voltage generation unit 32a and / or the second voltage generation unit 32b function as voltage pulse generation units configured to generate a sequence of voltage pulses. Thus, the sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. In one embodiment, the sequence of voltage pulses has multiple cycles, each cycle including a burst of voltage pulses in a first period and a constant reference voltage in a second period. That is, in the sequence of voltage pulses, bursts of voltage pulses are repeated. The absolute value of the voltage level of the voltage pulse is greater than the absolute value of the voltage level of the reference voltage. The voltage pulse may have an arbitrary waveform having a rectangular, trapezoidal, triangular, or a combination thereof, and the arbitrary waveform may change over time. The voltage pulse may have positive polarity or negative polarity. The sequence of voltage pulses may also include one or more positive voltage pulses and one or more negative voltage pulses within one cycle. The first and second voltage generation units 32a and 32b may be provided in addition to the power supply 31, and the first voltage generation unit 32a may be provided in place of the second RF generation unit 31b.

[0034] The exhaust system 40 may be connected to, for example, a gas outlet located at the bottom of the plasma processing chamber 10. The exhaust system 40 may also include a pressure regulating valve and a vacuum pump (exhaust pump). The pressure regulating valve regulates the pressure in the plasma processing space. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0035] The control unit 2 processes computer 2a-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described herein. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, some or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 is implemented, for example, by computer 2a. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The functions implemented by the processing unit 2a1 described herein may be implemented in a circuit or processing circuitry, including a general-purpose processor, an application-specific processor, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (Central Processing Unit), conventional circuitry, and / or a combination thereof, programmed to implement the functions described herein. A processor is considered a circuit or processing circuit, including transistors and other circuitry. A processor may be a programmed processor that executes a program P stored in the storage unit 2a2. This program P may be stored in the storage unit 2a2 in advance, or it may be retrieved via a medium when needed. The retrieved program P is stored in the storage unit 2a2 and read from the storage unit 2a2 and executed by the processing unit 2a1. The medium may be various storage media M readable by the computer 2a, or it may be a communication line connected to the communication interface 2a3. The storage unit 2a2 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).In this disclosure, circuits, units, and means are hardware programmed to perform or configured to perform the functions described. Such hardware may be any hardware described in this disclosure, or any hardware known to be programmed to perform or execute the functions described. If such hardware is a processor that is considered to be a type of circuit, such circuit, means, or unit is a combination of hardware and software used to constitute such hardware and / or processor.

[0036] The memory unit 2a2 of the control unit 2, implemented by computer 2a, stores a program P (program product) that controls the first gas supply mechanism 51 and the second gas supply mechanism 52, as well as an actual file of a learning model 200 that outputs information regarding the pressure to be increased by the gas supply mechanism when process condition information is input. Furthermore, the memory unit 2a2 of the control unit 2 stores reference data, parameter sheets, various tables, etc., used by the control unit 2 when performing various controls or processes, such as processing recipes when executing film deposition processes. Moreover, when the control unit 2 performs various controls or processes, it may store acquired sensor values ​​or generated intermediate data in the memory unit 2a2, associating them with time information (time stamp) indicating the time of acquisition or generation.

[0037] Figure 2 is an explanatory diagram showing an example of the time course of gas piping pressure and gas flow rate. This diagram shows, for example, the process of supplying and shutting off the first gas, which is the raw material gas, to the plasma processing chamber 10 in a time chart, with the horizontal axis representing time. In this diagram, the upper graph shows the change in the pressure inside the first gas piping 51c, and the vertical axis represents the pressure value inside the piping, which shows the difference relative to a defined reference value, such as 10 [Torr]. When the pressure inside the piping matches the reference value, it is shown as 0 [Torr]. In this diagram, the lower graph shows the gas flow rate in the first gas piping 51c, and the vertical axis is shown, for example, in sccm (Standard Cubic Centimeter per Minute).

[0038] The control unit 2 controls the first flow controller 51b and the first valve 51d included in the first gas supply mechanism 51, thereby repeatedly supplying and shutting off the first gas to the plasma processing chamber 10 at a predetermined cycle. Then, the control unit 2 reverses the phase of the supply and shut-off processes for the first gas and controls the second flow controller 52b and the second valve 52d included in the second gas supply mechanism 52, thereby repeatedly supplying and shutting off the second gas to the plasma processing chamber 10 at a predetermined cycle. In this way, the control unit 2 alternately supplies the first gas to the plasma processing chamber 10 and the second gas to the plasma processing chamber 10, that is, reverses the phase of supply and shut-off. In the following description, "gas" refers to either the first gas or the second gas.

[0039] When supplying gas, for example, gas is supplied at a desired flow rate of approximately 180 sccm, and the stable pressure inside the piping at that time is set to 0 Torr as the reference. The control unit 2 switches between supplying and shutting off the gas at regular intervals of a few seconds, and when the gas is shut off, it constantly calculates the flow rate to the gas flow controller so that the pressure inside the piping becomes, for example, +10 Torr relative to the reference, and controls the gas flow rate by sending an instruction to the gas flow controller.

[0040] As described above, the upper graph (a) shows the time course of the measured pressure inside the piping, and the lower graph (b) shows the time course of the measured gas flow rate derived from the gas flow controller. The dotted line indicates the timing of the switch between gas supply and shutoff to the plasma processing chamber 10 (processing chamber). As shown in the upper graph (a), when the shutoff by the control unit 2 is initiated, the amount of gas supplied from the gas flow controllers (first flow controller 51b, second flow controller 52b) to the piping (first gas piping 51c, second gas piping 52c) is gradually reduced, while the pressure inside the piping is increased so that it becomes +10 Torr relative to the reference.

[0041] Within a few seconds of the shutoff by the control unit 2, the pressure inside the piping reaches +10 Torr relative to the reference. The pressure at the point when it reaches +10 Torr relative to the reference corresponds to the first pressure in the first gas piping 51c or the second pressure in the second gas piping 52c. At this time, that is, when the pressure inside the piping reaches +10 Torr relative to the reference, the gas flow rate calculated to stabilize the pressure in the blocked piping (first gas piping 51c, second gas piping 52c) at +10 Torr is 0 sccm, and therefore, the gas flow rate measurement indicates that the output flow rate from the gas flow controllers (first flow controller 51b, second flow controller 52b) is 0 sccm.

[0042] After a certain period of time has elapsed since the shutoff, the gas supply is switched on, and the control unit 2 instructs the gas flow controllers (first flow controller 51b, second flow controller 52b) to a desired flow rate of approximately 180 sccm during gas supply. Meanwhile, the pressure inside the piping gradually decreases from a pressure of +10 Torr relative to the reference pressure to a reference pressure (a pressure where the difference from the reference pressure is 0 Torr), which is the stable pressure when approximately 180 sccm of gas is flowing. The control unit 2 then repeats the above process at regular intervals.

[0043] Figure 3 is an explanatory diagram illustrating an example of shortening the gas exchange time in the chamber (processing chamber) by increasing the pressure in the gas piping. This figure shows the results of confirming the effect of shortening the gas introduction time in the processing chamber (plasma processing chamber 10) by controlling the control unit 2 shown in this embodiment, that is, increasing the pressure in the first gas piping 51c to a first pressure and increasing the pressure in the second gas piping 52c to a second pressure. This figure may also show the results of measuring the emission of oxygen gas in the plasma generated in the processing chamber (plasma processing chamber 10) using an emission spectrometer.

[0044] This figure shows three types of measurement results. In this figure, the horizontal axis represents elapsed time, and the vertical axis represents the concentration of the gas (first gas or second gas) in the plasma processing chamber 10. The dotted line (without Proposal) shows the case where this embodiment is not used and the gas (first gas, second gas) is supplied from the gas flow controllers (first flow controller 51b, second flow controller 52b). The dashed line (with Proposal (A)) shows the case where this embodiment is used, and the pressure inside the piping at the time of shutoff is set to the same pressure as at the time of supply, and the valves (first valve 51d, second valve 52d) that were closed directly above the processing chamber at the time of supply are opened to supply gas to the processing chamber (plasma processing chamber 10). The solid line (with Proposal (B)) shows the case where this embodiment is used, and the pressure in the piping at the time of shutoff is increased to +10 Torr compared to the supply pressure. The control unit 2 switches between shutting off and supplying gas at the timing indicated by the vertical dotted line in this diagram. To the left of the vertical dotted line, no gas such as oxygen is supplied, and the supply of gas such as oxygen begins at the timing indicated by the vertical dotted line.

[0045] As shown in this figure, by comparing the dotted line (without using this embodiment) and the dashed line (with using this embodiment), it can be seen that using this embodiment shortens the time required for gas introduction into the processing chamber (plasma processing chamber 10) and for stabilization compared to when this embodiment is not used. Furthermore, by comparing the dashed line (with using this embodiment) and the solid line (with using this embodiment [+10 Torr]), it can be seen that by using this embodiment and further increasing the shut-off pressure compared to the supply pressure, the time required for gas introduction into the processing chamber (plasma processing chamber 10) and for stabilization is further shortened.

[0046] Thus, the higher the internal pressure of the gas piping when the gas supply to the processing chamber (plasma processing chamber 10) is shut off, the shorter the time required to switch from the pre-treatment gas to the next-processing gas. However, if the internal pressure of the gas piping becomes excessively high, there is a concern that when switching from shutoff to supply, the concentration of the gas supplied to the processing chamber (plasma processing chamber 10) will exceed a predetermined target value, resulting in an overshoot. To address this, the optimal value of the internal pressure of the gas piping, i.e., the first pressure in the first gas piping 51c or the second pressure in the second gas piping 52c, is desirable to be a pressure at which the amount of gas supplied is equal to the pressure at which the gas supply path (downstream first gas piping 51c, downstream second gas piping 52c) from the switching valve (first valve 51d, second valve 52d) to the processing chamber (plasma processing chamber 10) stabilizes when a predetermined gas flow rate for the next processing is flowed.

[0047] This pressure may also be determined from the ideal gas law and the gas flow path volumes before and after the switching valve as follows. These gas flow path volumes are pre-stored in the memory unit 2a2. That is, the gas flow path volumes etc. used in the calculation below may be those included in the processing recipes stored in the memory unit 2a2. Let V1 be the volume of the gas flow path (pre-stage first gas pipe 51c, pre-stage second gas pipe 52c) before the switching valve (first valve 51d, second valve 52d) that stores gas, T1 be its temperature, and P1 be the pressure in the flow path. On the other hand, let V2 be the volume of the gas flow path (post-stage first gas pipe 51c, post-stage second gas pipe 52c) after the switching valve (first valve 51d, second valve 52d), T2 be its temperature, and P2 be the pressure in the flow path. From the ideal gas law, the relationships between them are as follows. P1 × V1 = n × R × T1 ... (1) P2 × V2 = n × R × T2 ... (2)

[0048] To supply the amount of gas such that the pressure in the gas flow path downstream of the switching valve becomes the same as the pressure at which the predetermined gas flow rate for the next process stabilizes, the gas flow path upstream of the switching valve should be set to a pressure such that the number of moles n in equations (1) and (2) are the same. For example, if the pressure downstream of the switching valve is set to Pstable (the optimal pressure), the pressure upstream of the switching valve can be calculated using the following equation (3). P1={(V2×T1) / (V1×T2)}×Pstable...(3)

[0049] If T1 and T2 can be considered to be at the same temperature, equation (3) can be simplified and can be calculated using equation (4) from the volume ratio before and after the switching valve and the desired downstream pressure. P1 = (V2 / V1) × Pstable ···(4)

[0050] The control unit 2 can acquire various values ​​(input factors) such as pressure and temperature used in the above-described formula by acquiring detected values ​​from the first pressure gauge 51e, the second pressure gauge 52e, and the temperature sensors located in the first gas pipe 51c and the second gas pipe 52c.

[0051] The control unit 2 collects the type of gas used, the set flow rate of each gas, the set pressure in the processing chamber, and the ambient temperature of the piping during these processes. It may also use data collected on the relationship between these four points of data and the measured value of the piping pressure (Pstable in equation (3)) from the downstream of the switching valve (first valve 51d, second valve 52d) to the processing chamber (plasma processing device 1) to generate a learning model 200, which will be described later. The control unit 2 uses this past data, that is, the learning model 200 which has been trained using this past data as training data, to predict the optimal value (Pstable) of the pressure (pressure in the downstream gas flow path) in the next process. The control unit 2 can then predict the optimal pressure in the volume V1 piping (preceding gas passage: preceding first gas piping 51c or preceding second gas piping 52c) at the time of shutoff, based on the optimal pressure value (Pstable), the volume V1 of the gas passage upstream of the switching valve that stores gas, and the volume V2 of the piping from downstream of the switching valve to the processing chamber (plasma processing device 1), using the above-described equation (3) or equation (4).

[0052] In this embodiment, the control unit 2 predicts the optimal value (Pstable) of the pressure in the next processing stage (pressure in the subsequent gas flow path) using a learning model 200 based on the type of gas used, the set flow rate of each gas, the set pressure of the processing chamber, and the ambient temperature of the piping, and uses this optimal value (Pstable) and equation (3) or equation (4) to predict the optimal pressure of the volume V1 piping (preceding gas flow path: preceding first gas piping 51c or preceding second gas piping 52c) at the time of shutoff, but is not limited to this. The control unit 2 may also directly predict the optimal pressure of the volume V1 piping (preceding gas flow path: preceding first gas piping 51c or preceding second gas piping 52c) at the time of shutoff using the type of gas used, the set flow rate of each gas, the set pressure of the processing chamber, the ambient temperature of the piping, and data on the degree of gas component fluctuation in the processing chamber (plasma processing apparatus 1) measured by an OES (Optical Emission Spectrometer) or the like (gas component fluctuation data). In this case, the learning model 200 is trained to output the optimal pressure of the volume V1 piping (preceding gas flow path: preceding first gas piping 51c or preceding second gas piping 52c) at the time of shutoff, when process condition information including the type of gas used, the set flow rate of each gas, the set pressure of the processing chamber, the ambient temperature of the piping, and gas component fluctuation data is input.

[0053] In the explanations above, the switch from shut-off to supply is assumed to occur after the gas piping (first gas piping 51c, second gas piping 52c) has stabilized at a predetermined pressure. However, this is not limited to this, and if the reproducibility of the pressure changes within the piping is high, the switch from shut-off to supply may be made before the pressure stabilizes at the predetermined pressure.

[0054] Figure 4 is an explanatory diagram showing an example of a timing chart for valve operation, etc. In this embodiment, the diagram shows, as an example, a timing chart for the supply and shutoff of the first gas, with the horizontal axis representing elapsed time. The supply and shutoff of the second gas are controlled in the same way as the first gas, but the phase of supply and shutoff is inverted between the supply and shutoff control for the second gas and the supply and shutoff control for the first gas.

[0055] The upper part of this figure shows the open or closed state of the first valve 51d. The middle part of this figure shows the transmission status of instructions from the control unit 2 to the first valve 51d regarding opening and closing control, i.e., the signal instructing it to open (open signal). The lower part of this figure shows the measured flow rate of the first gas flowing through the first gas piping 51c via the first valve 51d.

[0056] The timing of restarting the gas supply after it has been stopped may be the same as the timing of switching the gas piping, but if the response of the gas flow controller (first flow controller 51b) or the stabilization of the flow rate is slow, the timing may be set earlier than the timing of switching the gas piping, taking into account the time required for this. In other words, the control unit 2 may, taking into account the response of the gas flow controller (first flow controller 51b), instruct the first valve 51d to start control (send an open signal) at an earlier timing than the timing of opening the first valve 51d (V1 Open).

[0057] Figure 5 is an explanatory diagram regarding the generation process of the learning model 200 (pressure estimation model). The control unit 2 functions as a model server that generates or updates the learning model 200. Alternatively, another computer 2a (model server) different from the control unit 2 may generate or update the learning model 200. In this embodiment, the case in which the control unit 2 functions as a model server will be described. The control unit 2, functioning as a model server, trains a neural network using training data and generates a learning model 200 (pressure estimation model) that outputs information regarding the pressure to be increased by the gas supply mechanism when process condition information is input.

[0058] The training data used to generate the learning model 200 (pressure estimation model) consists of problem data, which includes process condition information such as the type of gas used, the set flow rate of each gas, the set pressure of the plasma processing chamber 10 (processing chamber), and the ambient temperature of the piping, collected from the operating conditions of the gas supply system S over a predetermined period; and answer data, which includes measured values ​​of the pressure (Pstable) in the piping from the downstream of the switching valve (first valve 51d, second valve 52d) to the plasma processing device 1 (downstream first gas piping 51c, downstream second gas piping 52c). This training data is stored in the storage unit 2a292 of the control unit 2. This training data can be generated, for example, by aggregating operating condition data from multiple gas supply systems S.

[0059] The learning model 200 (pressure estimation model) is configured, for example, using a DNN (Deep Neural Network), and has an input layer that accepts process condition information, an intermediate layer that extracts feature quantities of the process condition information, and an output layer that outputs the pressure (Pstable) value of the piping (downstream first gas piping 51c, downstream second gas piping 52c) from the downstream of the switching valve (first valve 51d, second valve 52d) to the plasma processing apparatus 1.

[0060] The input layer has multiple neurons that receive process condition information and passes the input values ​​to the hidden layer. The hidden layer is defined using an activation function such as a ReLU function or a sigmoid function and has multiple neurons that extract feature quantities from each input value and passes the extracted feature quantities to the output layer. Parameters such as the weighting coefficient and bias value of the activation function are optimized using backpropagation. The output layer is composed of, for example, a fully connected layer and outputs the pressure (Pstable) value of the piping (downstream first gas piping 51c, downstream second gas piping 52c) from the downstream of the switching valve (first valve 51d, second valve 52d) to the plasma processing apparatus 1 based on the feature quantities output from the hidden layer.

[0061] In this embodiment, the process condition information input to the learning model 200 (pressure estimation model) includes, but is not limited to, the type of gas used, the set flow rate of each gas, the set pressure of the plasma processing chamber 10 (processing chamber), and the ambient temperature of the piping. The process condition information may also include, but is not limited to, data on the degree of gas component fluctuation of the plasma processing apparatus 1 (gas component fluctuation data). In this case, the learning model 200 (pressure estimation model) into which the process condition information is input may estimate the pressure of the piping (preceding first gas piping 51c, preceding second gas piping 52c) preceding the switching valve (first valve 51d, second valve 52d). Alternatively, if the gas supply system S includes a third gas supply mechanism 53 that supplies a purge gas such as argon, the process condition information may, in addition to the above-mentioned items, further include one or more of the type of gas used for the third gas and the set flow rate of the gas.

[0062] The datasets containing problem data and response data included in the training data for learning model 200 (pressure estimation model) and the datasets containing input data and output data when using learning model 200 (pressure estimation model) are synonymous. If a definition is defined in one dataset, it will naturally apply to the other dataset as well.

[0063] While the learning model 200 (pressure estimation model) is assumed to be constructed using a DNN, it is not limited to this. For example, the learning model 200 may be constructed using other machine learning algorithms such as CNN (Convolutional Neural Network), Transformer, BERT, GPT, RNN (Recurrent Neural Network), LSTM (Long-short term model), SVM (Support Vector Machine), Bayesian network, linear regression, regression tree, multiple regression, random forest, or ensemble. Alternatively, the learning model 200 may be constructed using a pre-trained language model (LLM) that has already undergone pre-training, such as ChatGPT. In this case, the LLM may be fine-tuned to efficiently output pressure-related information. Alternatively, a question generated using an external database such as WebDB may be input along with process condition information to the prompt, which is the input interface of ChatGPT.

[0064] Figure 6 is a flowchart illustrating the processing performed by the control unit 2. The control unit 2 of the gas supply system S of the semiconductor manufacturing apparatus performs substrate processing (film formation) by the ALD (Atomic Layer Deposition) process, or etching processing by the ALE (Atomic Layer Etch) process, according to the flowchart below. At this time, the object to be processed W is placed on the substrate support unit 11.

[0065] The control unit 2 of the gas supply system S acquires a processing recipe (S101). The control unit 2 acquires the processing recipe by referring to the storage unit 2a2. The processing recipe includes various data, such as process condition information used in performing the film deposition process in this embodiment.

[0066] The control unit 2 of the gas supply system S executes the first step for a predetermined period (S102). Based on the acquired processing recipe, the control unit 2 of the gas supply system S executes the first step for a predetermined period, i.e., at a predetermined cycle. By executing the first step, the first valve 51d is opened and the second valve 52d is closed. Then, the first flow rate controller 51b supplies the first gas at a predetermined flow rate to the gas diffusion chamber 13b. In the illustration of this embodiment, in the first first step, the process of raising the pressure to the first level is not performed before the first first step, but this is not limited to this, and the processes from S106 to S108 may be performed before the first first step. These processes from S106 to S108 will be described later.

[0067] The control unit 2 of the gas supply system S performs the processes from S103 to S105 in parallel during a predetermined period in which the first process is executed (while S102 is being executed). That is, the control unit 2 performs the processes from S103 to S105 while the second valve 52d is closed.

[0068] The control unit 2 of the gas supply system S acquires process condition information for the second process (S103). The control unit 2 acquires process condition information for the second process, namely the type of gas used in the second gas supply mechanism 52, the set flow rate of each gas, the set pressure of the plasma processing chamber 10 (processing chamber), and the ambient temperature of the piping. The type of gas used in the second gas supply mechanism 52, the set flow rate of each gas, and the set pressure of the plasma processing chamber 10 (processing chamber) may be included in the processing recipe. The control unit 2 may also acquire the ambient temperature of the piping from a temperature sensor provided in the second gas supply mechanism 52.

[0069] The control unit 2 of the gas supply system S derives a second pressure (S104). The control unit 2 inputs process condition information for the second process, including the type of gas used in the second gas supply mechanism 52, the set flow rate of each gas, the set pressure of the plasma processing chamber 10 (processing chamber), and the ambient temperature of the piping, into the learning model 200, and obtains the pressure (Pstable) of the downstream second gas piping 52c from the learning model 200.

[0070] The control unit 2 derives a second pressure based on the acquired pressure (Pstable) of the downstream second gas pipe 52c and the volume ratio (V2 / V1) of the upstream second gas pipe 52c (V2) and the downstream second gas pipe 52c (V1), using, for example, equation (3) or (4) described above. When using equation (3), the control unit 2 may also derive the second pressure using the temperature ratio (T1 / T2) of the ambient temperature (T1) of the upstream second gas pipe 52c and the ambient temperature (T2) of the downstream second gas pipe 52c.

[0071] The control unit 2 of the gas supply system S increases the pressure of the second gas in the second gas pipe 52c to the second pressure (S105). With the second valve 52d closed, the control unit 2 continues to supply the second gas from the second flow controller 52b, increasing the pressure of the second gas in the second gas pipe 52c to the derived second pressure. After reaching the second pressure, the control unit 2 sets the flow rate of the second gas from the second flow controller 52b to zero and maintains the pressure at the second pressure.

[0072] The control unit 2 of the gas supply system S executes the second process for a predetermined period (S109). After the completion of the first process at a predetermined cycle, the control unit 2 of the gas supply system S executes the second process at a predetermined period, i.e., a predetermined cycle, based on the acquired processing recipe. By executing the second process, the second valve 52d is opened and the first valve 51d is closed. Then, the second flow controller 52b supplies the second gas at a predetermined flow rate to the gas diffusion chamber 13b. At this time, the pressure of the second gas in the second gas piping 52c has risen to the second pressure, so the flow velocity of the second gas flowing into the gas diffusion chamber 13b can be improved.

[0073] The control unit 2 of the gas supply system S performs the processes from S106 to S108 in parallel during a predetermined period in which the second process is executed (while S109 is being executed). That is, the control unit 2 performs the processes from S106 to S108 while the first valve 51d is closed.

[0074] The control unit 2 of the gas supply system S acquires process condition information for the first process (S106). The control unit 2 acquires process condition information for the first process, namely the type of gas used in the first gas supply mechanism 51, the set flow rate of each gas, the set pressure of the plasma processing chamber 10 (processing chamber), and the ambient temperature of the piping. The type of gas used in the first gas supply mechanism 51, the set flow rate of each gas, and the set pressure of the plasma processing chamber 10 (processing chamber) may be included in the processing recipe. The control unit 2 may also acquire the ambient temperature of the piping from a temperature sensor provided in the first gas supply mechanism 51.

[0075] The control unit 2 of the gas supply system S derives a first pressure using the learning model 200 (S107). The control unit 2 inputs process condition information for the first process, including the type of gas used in the first gas supply mechanism 51, the set flow rate of each gas, the set pressure of the plasma processing chamber 10 (processing chamber), and the ambient temperature of the piping, into the learning model 200, thereby obtaining the pressure (Pstable) of the downstream first gas piping 51c from the learning model 200.

[0076] The control unit 2 derives a first pressure based on the acquired pressure (Pstable) of the downstream first gas pipe 51c and the volume ratio (V2 / V1) of the upstream first gas pipe 51c (V2) and the downstream first gas pipe 51c (V1), using, for example, the aforementioned equation (3) or (4). When using equation (3), the control unit 2 may also derive the first pressure using the temperature ratio (T1 / T2) of the ambient temperature (T1) of the upstream first gas pipe 51c and the ambient temperature (T2) of the downstream first gas pipe 51c.

[0077] The control unit 2 of the gas supply system S increases the pressure of the first gas in the first gas piping 51c to a first pressure (S108). With the first valve 51d closed, the control unit 2 continues to supply the first gas from the first flow controller 51b, increasing the pressure of the first gas in the first gas piping 51c to the derived first pressure. After reaching the first pressure, the control unit 2 sets the flow rate of the second gas from the first flow controller 51b to zero and maintains the pressure at the first level. As a result, when executing the next first step, the pressure of the first gas in the first gas piping 51c has risen to the first pressure, which improves the flow velocity of the first gas flowing into the gas diffusion chamber 13b.

[0078] The control unit 2 of the gas supply system S determines whether the first and second steps have been executed a predetermined number of times (S110). The number of times the first and second steps are repeated alternately may be included as a predetermined number in the processing recipe, for example, and the control unit 2 of the gas supply system S may compare the predetermined number included in the processing recipe with the number of times the first and second steps have been repeated alternately executed up to that point to determine whether the first and second steps have been executed the predetermined number of times.

[0079] If the predetermined number of executions has not been performed (S110: NO), the control unit 2 of the gas supply system S performs a loop process to execute the processes from S102 and S103 again. If the predetermined number of executions have been performed (S110: YES), the control unit 2 of the gas supply system S executes the series of processes in this flow.

[0080] In this embodiment, the control unit 2 performs a process to derive the second pressure or the first pressure each time the first or second step is performed, but is not limited to this. The control unit 2 may also perform a process to derive the second pressure and the first pressure in a preparation step before performing the first and second steps. Furthermore, while the process of alternately repeating the first and second steps is in progress, the control unit 2 may use the first pressure and the second pressure derived in the preparation step to increase the pressure of the first gas in the first gas pipe 51c and the pressure of the first gas in the second gas pipe 52c. Alternatively, the control unit 2 does not have to perform a process to derive the second pressure and the first pressure each time the process of alternately repeating the first and second steps is performed; for example, it may derive the second pressure and the first pressure each time the process of alternately repeating the first and second steps is performed a predetermined number of times.

[0081] In this embodiment, a first step of plasma-treating a workpiece W using a first gas and a second step of plasma-treating a workpiece W using a second gas are alternately repeated in the chamber of the semiconductor manufacturing apparatus, and the pressure in the chamber is maintained at a reference pressure such as 10 Torr by the exhaust system 40. The control unit 2 of the gas supply system S closes the first valve 51d before performing the first step of supplying the first gas to the chamber through the first gas pipe 51c to the diffusion chamber and plasma-treating the workpiece W. Then, the control unit 2 of the gas supply system S controls the first gas supply mechanism 51, that is, it controls the flow rate of the first gas by constantly calculating the flow rate from the first flow controller 51b included in the first gas supply mechanism 51 and transmitting an instruction signal to the first flow controller 51b so that the pressure of the first gas in the first gas pipe 51c is raised to the first pressure by the first gas. Therefore, the first pressure can be set higher than the reference pressure in the chamber. By raising the pressure of the first gas in the first gas piping 51c to the first pressure before the first process, the flow velocity of the first gas when it flows into the chamber can be increased when the first valve 51d is opened to start the first process, and the gas exchange from the second gas to the first gas in the chamber can be completed quickly and in a short amount of time.

[0082] Furthermore, the control unit 2 of the gas supply system S closes the second valve 52d before performing the second step of supplying the second gas to the chamber through the second gas pipe 52c and through the diffusion chamber to perform plasma treatment on the object to be treated W. Then, the control unit 2 of the gas supply system S controls the second gas supply mechanism 52, that is, it constantly calculates the flow rate from the second flow controller 52b (MFC2) included in the second gas supply mechanism 52 and controls the flow rate of the second gas by sending an instruction signal to the second flow controller 52b (MFC2) so that the pressure of the second gas in the second gas pipe 52c is raised to the second pressure by the second gas.Therefore, the second pressure can be made higher than the reference pressure in the chamber. In this way, by increasing the pressure of the second gas in the second gas piping 52c to the second pressure before the second process, when the second valve 52d is opened to start the second process, the flow velocity of the second gas as it flows into the chamber can be increased, and the gas exchange from the first gas to the second gas in the chamber can be completed quickly and in a short amount of time. In other words, in the process of transitioning conditions from the first process to the second process, and from the second process to the first process (transition process), the period during which the first gas and the second gas are mixed can be efficiently shortened, and a decrease in the yield of plasma processing can be suppressed.

[0083] Furthermore, in the case of the first and second gases, in order to maintain the flow rate of gases not supplied into the chamber, it is possible to eliminate the need to discharge them to the outside (outside the chamber) by using, for example, bypass piping. Therefore, it is possible to reduce gases that do not directly contribute to the treatment and conserve resources. In this case, the bypass piping can also be eliminated, so the bypass piping itself and the valves attached to it can be eliminated, resulting in resource conservation, reduced product costs, and smaller product size.

[0084] According to this embodiment, the memory unit 2a2 of the control unit 2, which is composed of a computer 2a or the like, stores a learning model 200 that outputs information regarding the pressure to be increased by the gas supply mechanism when process condition information is input. The process condition information includes, for example, one of the following: the type of gas used, the set flow rate of the gas, the set pressure of the chamber (processing chamber), the ambient temperature of the piping, and data on the degree of gas component fluctuation in the chamber (processing chamber). In this case, the individual process condition information is included, for example, in the processing recipe, or in sensor values ​​(detected values) obtained from various sensors such as a flow sensor, pressure sensor, temperature sensor, or OES (Optical Emission Spectrometer) provided in the semiconductor manufacturing apparatus or gas supply system S. The control unit 2 obtains process condition information for each of the first and second processes by referring to the processing recipe or obtaining sensor values ​​(detected values) from various sensors. When performing the first process, the control unit 2 inputs the process condition information for the first process into the learning model 200, and obtains information regarding the first pressure from the learning model 200. Furthermore, when performing the second process, the control unit 2 inputs the process condition information for the second process into the learning model 200, thereby acquiring information regarding the second pressure from the learning model 200. In this way, the control unit 2 acquires information regarding the first pressure and information regarding the second pressure by using the learning model 200, and can efficiently control the first gas supply mechanism 51 and the second gas supply mechanism 52 using the acquired information.

[0085] According to this embodiment, the learning model 200 outputs the pressure of the downstream first gas pipe 51c based on the process condition information of the first process, and outputs the pressure of the downstream second gas pipe 52c based on the process condition information of the second process. In this case, the process condition information of the first or second process includes the type of gas used in each process, the set flow rate of each gas, the set pressure of the chamber (processing chamber), and the ambient temperature of the piping (ambient temperature of the first gas pipe 51c in the first process, and ambient temperature of the second gas pipe 52c in the second process). The pressure information output by the learning model 200 indicates the optimal value (optimal pressure: Pstable) of the piping pressure from downstream of the valve to the chamber (processing chamber). The control unit 2 uses the optimal pressure (Pstable) from the learning model 200 to derive the pressure in the gas flow path before the valve, i.e., the first pressure (the target pressure value of the first gas in the first gas pipe 51c) or the second pressure (the target pressure value of the second gas in the second gas pipe 52c), based on the ratio of the gas flow path volume before the valve (V1) and the gas flow path volume after the valve (V2). In this way, the optimal value (optimal pressure: Pstable) for the piping pressure from the stage after the valve to the chamber (processing chamber) is estimated using the learning model 200, and then the pressure in the piping before the valve (first pressure, second pressure) is derived based on the volume ratio of the gas piping before and after the valve. This makes it possible to efficiently derive the pressure in the piping before the valve (first pressure, second pressure) according to the location of the valve in the gas piping or the inner diameter of the gas piping, thereby improving the availability of the gas supply system S.

[0086] (Embodiment 2) Figure 7 is a diagram illustrating an example configuration of a capacitively coupled plasma processing apparatus 1 according to Embodiment 2 (multiple diffusion chambers). In this embodiment, the gas supply system S includes a first gas supply mechanism 51 and a second gas supply mechanism 52, and a gas flow diversion mechanism 6, similar to Embodiment 1. The plasma processing apparatus 1 includes a shower head 13, etc., similar to Embodiment 1.

[0087] The gas diversion mechanism 6 includes a diversion channel 61 and a diversion valve 62, similar to Embodiment 1. The diversion channel 61 includes a diversion channel 611 connected to the first gas supply mechanism 51 and a diversion channel 612 connected to the second gas supply mechanism 52. The diversion valve 62 includes a diversion valve 621 connected to the first gas supply mechanism 51 and a diversion valve 621 connected to the second gas supply mechanism 52.

[0088] The first gas pipe 51c downstream of the first valve 51d is branched, and each branched first gas pipe 51c is connected to each diversion valve 621 via a parallel diversion channel 612. Each diversion channel 611 extending from each diversion valve 621 connected to the first gas supply mechanism 51 is connected to the shower head 13.

[0089] The second gas pipe 52c downstream of the second valve 52d is branched, and each branched second gas pipe 52c is connected to each of the diversion valves 622 via a parallel diversion channel 612. Each diversion channel 61 extending from each of the diversion valves 622 connected to the second gas supply mechanism 52 is connected to the shower head 13.

[0090] The shower head 13 includes a gas diffusion chamber 13b, similar to Embodiment 1, and the gas diffusion chamber 13b includes a gas diffusion chamber 13b1 connected to a first gas supply mechanism 51 and a gas diffusion chamber 13b2 connected to a second gas supply mechanism 52. In this embodiment, the gas diffusion chamber 13b1 connected to the first gas supply mechanism 51 is located above the gas diffusion chamber 13b2 connected to the second gas supply mechanism 52, but is not limited to this and may be located below.

[0091] The gas diffusion chamber 13b connected to the first gas supply mechanism 51 and the gas diffusion chamber 13b connected to the second gas supply mechanism 52 each include one or more gas supply ports 13a and gas inlets 13c. That is, the gas diffusion chamber 13b1 connected to the first gas supply mechanism 51 includes one or more gas supply ports 13a1 and gas inlets 13c1. The gas diffusion chamber 13b2 connected to the second gas supply mechanism 52 includes one or more gas supply ports 13a2 and gas inlets 13c2.

[0092] Each of the diversion channels 611 extending from each of the diversion valves 621 connected to the first gas supply mechanism 51 is connected to the gas supply port 13a1 of the gas diffusion chamber 13b1 connected to the first gas supply mechanism 51. Each of the diversion channels 612 extending from each of the diversion valves 622 connected to the second gas supply mechanism 52 is connected to the gas supply port 13a2 of the gas diffusion chamber 13b2 connected to the second gas supply mechanism 52.

[0093] Thus, a gas shower (shower head 13) is used to ensure a uniform amount of gas is introduced onto the surface of the Wafer (workpiece W). The gas shower (shower head 13) is provided with a diffusion layer (gas diffusion chamber 13b) to uniformly diffuse the gas in a planar manner. In Embodiment 1, there is only one diffusion layer (gas diffusion chamber 13b), but in this embodiment, the plasma processing apparatus 1 may include multiple diffusion layers (gas diffusion chambers 13b1, gas diffusion chambers 13b2) as shown in the figure, in order to prevent the gases to be exchanged from mixing.

[0094] According to this embodiment, the diffusion chamber of the gas supply system S includes a first diffusion chamber communicating with the first gas pipe 51c and a second diffusion chamber communicating with the second gas pipe 52c. Therefore, it is possible to prevent the first gas and the second gas from mixing in each of the first and second diffusion chambers. Since the shower head 13 is divided into a first diffusion chamber and a second diffusion chamber in this way, it is possible to prevent the first gas and the second gas from mixing in the shower head 13 during the transition process between the first and second processes.

[0095] (Embodiment 3) Figure 8 is a diagram illustrating an example configuration of a capacitively coupled plasma processing apparatus 1 according to Embodiment 3 (third gas). In this embodiment, the gas supply system S includes a first gas supply mechanism 51 and a second gas supply mechanism 52, a gas diversion mechanism 6, and a third gas supply mechanism 53, similar to Embodiment 2. The configurations of the first gas supply mechanism 51, the second gas supply mechanism 52, and the gas diversion mechanism 6 are the same as in Embodiment 2. The third gas supply mechanism 53 includes a third gas source 53a, a third flow controller 53b1, 53b2, a third gas piping 53c1, 53c2, and a third valve 53d1, 53d2, similar to the first gas supply mechanism 51 or the second gas supply mechanism 52.

[0096] The third gas source 53a stores an inert gas such as a rare gas, such as argon gas, which has a small contribution to the film formation process. The third gas source 53a has two third gas pipes 53c1 and 53c2 extending in parallel. One third gas pipe 53c1 is connected to the first gas pipe 51c (downstream first gas pipe 51c) downstream of the first valve 51d, and the other third gas pipe 53c2 is connected to the second gas pipe 52c (downstream second gas pipe 52c) downstream of the second valve 52d.

[0097] A third flow controller 53b1 and a third valve 53d1 are located in one of the third gas pipes 53c1. A third flow controller 53b2 and a third valve 53d2 are located in the other third gas pipe 53c2. Each of these third gas pipes 53c1 and 53c2 may also be equipped with a pressure gauge or a temperature sensor, similar to the first gas pipe 51c or the second gas pipe 52c. The control unit 2 may acquire detected values ​​from the pressure gauges located in the third gas pipes 53c1 and 53c2, or from the temperature sensors located around the third gas pipes 53c1 and 53c2, and store them in the storage unit 2a2.

[0098] By using this configuration, in order to prevent the introduced gas from flowing back into the diffusion layer (gas diffusion chamber 13b) connected to the gas piping where the gas introduction is blocked, the gas supply system S may be configured to carry gases that have little contribution to the film formation process, such as inert gases like Ar, or common gases that are always needed, as shown in this figure.

[0099] Figure 9 is an explanatory diagram showing an example of a timing chart for valve operation, etc. (continuous supply of the third gas). The control unit 2 controls the opening and closing of the first valve 51d (V1), the second valve 52d (V2), the third valve 53d2 (V5) connected to the second gas supply mechanism 52, and the third valve 53d1 (V6) connected to the first gas supply mechanism 51, thereby alternately supplying and shutting off the first and second gases, and continuously or intermittently supplying a third gas such as argon. At this time, the control unit 2 controls the third flow controllers 53b1 and 53b2 in the third gas piping 53c1 and 53c2 so that the third gas flows at a predetermined flow rate.

[0100] In this figure, the horizontal axis represents elapsed time. From top to bottom, this figure shows the presence or absence of the first gas flow rate, the presence or absence of the second gas flow rate, the presence or absence of the third gas flow rate, the open / closed state of the first valve 51d(V1), the open / closed state of the second valve 52d(V2), the open / closed state of the third valve 53d2(V5) connected to the second gas supply mechanism 52, and the open / closed state of the third valve 53d1(V6) connected to the first gas supply mechanism 51.

[0101] When the control unit 2 supplies the first gas to the gas diffusion chamber 13b and shuts off the second gas, it opens the first valve 51d(V1) and closes the second valve 52d(V2). Then, the control unit 2 continues to supply the third gas to the gas diffusion chamber 13b, opening the third valve 53d2(V5) connected to the second gas supply mechanism 52 and closing the third valve 53d1(V6) connected to the first gas supply mechanism 51.

[0102] When the control unit 2 supplies the second gas to the gas diffusion chamber 13b and shuts off the first gas, it closes the first valve 51d(V1) and opens the second valve 52d(V2). Then, the control unit 2 continues to supply the third gas to the gas diffusion chamber 13b, and in doing so, it closes the third valve 53d2(V5) connected to the second gas supply mechanism 52 and opens the third valve 53d1(V6) connected to the first gas supply mechanism 51.

[0103] Figure 10 is an explanatory diagram showing an example of a timing chart for valve operation, etc. (intermittent supply of the third gas). The configuration in this figure is the same as in Figure 9. When the control unit 2 supplies the first gas to the gas diffusion chamber 13b and shuts off the second gas, it opens the first valve 51d (V1) and closes the second valve 52d (V2). Then, when the control unit 2 supplies the third gas to the gas diffusion chamber 13b, it does so intermittently. That is, after the control unit 2 supplies the first gas and the third gas to the gas diffusion chamber 13b simultaneously, it shuts off the third gas before shutting off the first gas.

[0104] When the control unit 2 supplies the second gas to the gas diffusion chamber 13b and shuts off the first gas, it closes the first valve 51d(V1) and opens the second valve 52d(V2). Then, when the control unit 2 supplies the third gas to the gas diffusion chamber 13b, it does so intermittently. That is, after the control unit 2 supplies both the second and third gases to the gas diffusion chamber 13b simultaneously, it shuts off the third gas before shutting off the second gas.

[0105] Furthermore, when the gas supply system S uses multiple gas flow controllers to supply a mixed gas of multiple gas types, it may distribute the calculated total gas flow rate to the flow rates of each gas in order to maintain the ratio of each gas to the components of the mixed gas. For example, if the mixed gas consists of gas A, gas B, and gas C, with a ratio of 5:2:3, and the calculated total flow rate of the mixed gas is 100 sccm, then the flow rate of gas A will be 50 sccm, the flow rate of gas B will be 20 sccm, and the flow rate of gas C will be 30 sccm.

[0106] According to this embodiment, the gas supply system S has a diversion valve 62 (gas diversion mechanism 6) provided in each of the multiple diversion channels 61 that supply gas to the diffusion chamber by diversion. Each of these diversion valves 62 provided in each of the multiple diversion channels 61 may be configured as a gas diversion mechanism 6 interposed between the multiple diversion channels 61, which are composed of a first gas pipe 51c and a second gas pipe 52c, etc., and the chamber. The control unit 2 of the gas supply system S, for example, when performing substrate processing in an ALD (Atomic Layer Deposition) process to deposit a predetermined film, calls up a processing recipe stored in the memory unit 2a2 and controls the semiconductor manufacturing equipment to perform the predetermined processing based on that processing recipe. At this time, the control unit 2 of the gas supply system S controls the opening degree of the diversion valve 62 based on the processing recipe so that the diversion ratio, which is the ratio of the gas flow rates flowing through each of the multiple diversion channels 61, becomes the target diversion ratio. This allows for the supply of mixed gases containing multiple types of gases while maintaining the ratio of each gas to the components of the mixed gas, and distributing the calculated total gas volume to the volume of each gas.

[0107] According to this embodiment, the gas supply system S further includes third gas pipes 53c1 and 53c2 for supplying a third gas (argon) used in the first and second steps, third valves 53d1 and 53d2 for controlling the communication between the third gas pipes 53c1 and 53c2 and the diffusion chamber by opening and closing them, and a third gas supply mechanism 53 for controlling the pressure of the third gas in the third gas pipes 53c1 and 53c2. The third gas is, for example, a noble gas such as Ar gas or He gas, or an inert gas (purge gas) such as N2 gas, and the purging process can be performed by supplying the third gas. In this case, the process condition information input to the learning model 200 includes either the type of gas used for the third gas used in such purging processes, etc., or the set flow rate of the gas. Therefore, even when performing substrate processing including purging processes, the learning model 200 can be used to obtain information regarding the first pressure and information regarding the second pressure, and the first gas supply mechanism 51 and the second gas supply mechanism 52 can be efficiently controlled using the obtained information.

[0108] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims, not in the sense described above, and all modifications within the sense and scope equivalent to the claims are intended.

[0109] With respect to the multiple claims described in the claims, they can be combined with each other regardless of the form of reference. Multiple dependent claims that depend on multiple claims may be described in the claims. Multiple dependent claims that depend on multiple dependent claims may also be described. Even if multiple dependent claims that depend on multiple dependent claims are not described, this does not limit the description of multiple dependent claims that depend on multiple dependent claims. [Explanation of Symbols]

[0110] S Gas Supply System W - Object to be processed 1. Plasma processing equipment (semiconductor manufacturing equipment) 10 Plasma processing chamber 11. Substrate support section 13 Shower head 13a Gas supply port 13b Gas Diffusion Chamber 13c Gas inlet 2 Control Unit 2a Computer 2a1 Processing Unit 2a2 Storage section 2a3 communication interface P Program (Program Product) M storage medium 200 Learning Models (Pressure Estimation Models) 30 Power Systems 31 Power supply 31a First RF generation unit 31b Second RF generation unit 32 Power supply 32a First voltage generation unit 32b Second voltage generation unit 40 Exhaust System 51. First gas supply mechanism 51a First gas source 51b First flow controller 51c First gas piping 51d First valve 51e First pressure gauge 52 Second gas supply mechanism 52a Second gas source 52b Second flow controller 52c Second gas piping 52d Second valve 52e Second pressure gauge 53. Third gas supply mechanism 53a Third gas source 53b1 Third flow controller 53b2 Third flow controller 53c1 Third gas piping 53c2 Third gas piping 53d1 Third valve 53d2 Third valve 6. Gas flow separation mechanism 61 Diversion channel 62 flow divider valve

Claims

1. A gas supply system for a semiconductor manufacturing apparatus, which alternately repeats a first step of supplying a first gas into a chamber through a first gas pipe and passing it through a diffusion chamber to perform plasma treatment on an object to be processed, and a second step of supplying a second gas into the chamber through a second gas pipe and passing it through the diffusion chamber to perform plasma treatment on the object to be processed, A first valve controls the communication between the first gas pipe and the diffusion chamber by opening and closing it, A second valve controls the communication between the second gas pipe and the diffusion chamber by opening and closing it, Before the first step, a first gas supply mechanism closes the first valve and increases the pressure of the first gas in the first gas piping to a first pressure using the first gas, Before the second step, a second gas supply mechanism closes the second valve and increases the pressure of the second gas in the second gas piping to the second pressure using the second gas, Includes a control unit that controls the first gas supply mechanism and the second gas supply mechanism. Gas supply system.

2. Multiple diversion channels supply gas to the aforementioned diffusion chamber by diverting the flow, Includes a flow-dividing valve provided in each of the multiple flow-dividing channels, The control unit controls the opening degree of the diversion valve so that the diversion ratio, which is the ratio of the gas flow rates through each of the plurality of diversion channels, becomes the target diversion ratio. The gas supply system according to claim 1.

3. The aforementioned diffusion chamber is A first diffusion chamber communicating with the first gas piping, A second diffusion chamber communicating with the second gas piping, The gas supply system according to claim 1.

4. The control unit, Process condition information for each of the first and second processes is obtained. By inputting the process condition information for the first process or the process condition information for the second process into a learning model that outputs information about the pressure to be increased by the gas supply mechanism when process condition information is input, information about the first pressure before the first process or information about the second pressure before the second process is obtained. The first gas supply mechanism is controlled using the information obtained regarding the first pressure before the first step, or the second gas supply mechanism is controlled using the information obtained regarding the second pressure before the second step. The gas supply system according to claim 1.

5. The aforementioned process condition information includes one of the following: the type of gas used, the set gas flow rate, the set pressure in the chamber, the ambient temperature of the piping, and data on the degree of gas component variation in the chamber. The gas supply system according to claim 4.

6. A third gas pipe for supplying the third gas used in the first and second steps, A third valve controls the communication between the third gas pipe and the diffusion chamber by opening and closing it, The system includes a third gas supply mechanism for controlling the pressure of the third gas in the third gas piping, The aforementioned process condition information includes one of the following: the type of gas used for the third gas, and the set flow rate of the gas. The gas supply system according to claim 5.

7. The first gas piping is divided by the first valve into an upstream first gas piping and a downstream first gas piping. The second gas piping is divided by the second valve into an upstream second gas piping and a downstream second gas piping. The pressure information output by the learning model is the pressure of the downstream first gas pipe or the pressure of the downstream second gas pipe. The control unit, When the pressure of the downstream first gas pipe is obtained from the learning model, the first pressure is derived based on the pressure of the downstream first gas pipe and the volume ratio of the upstream first gas pipe and the downstream first gas pipe. When the pressure of the downstream second gas pipe is obtained from the learning model, the second pressure is derived based on the pressure of the downstream second gas pipe and the volume ratio between the upstream second gas pipe and the downstream second gas pipe. The gas supply system according to claim 4.

8. A gas supply method for a semiconductor manufacturing apparatus gas supply system, comprising the alternating repetition of a first step of supplying a first gas into a chamber through a first gas pipe and passing it through a diffusion chamber to perform plasma treatment on an object to be processed, and a second step of supplying a second gas into the chamber through a second gas pipe and passing it through the diffusion chamber to perform plasma treatment on the object to be processed, The aforementioned gas supply system is A first valve controls the communication between the first gas pipe and the diffusion chamber by opening and closing it, The system includes a second valve that controls the communication between the second gas pipe and the diffusion chamber by opening and closing it. During the execution of the second step, the first gas supply mechanism, including the first valve, closes the first valve before the first step, and increases the pressure of the first gas in the first gas piping to a first pressure with the first gas. During the execution of the first step, the second gas supply mechanism, including the second valve, closes the second valve before the second step, thereby increasing the pressure of the second gas in the second gas piping to the second pressure using the second gas. Gas supply method.

9. When performing a plasma treatment process on a workpiece using semiconductor manufacturing equipment, process condition information is acquired. By inputting the acquired process condition information into a learning model that outputs information regarding the pressure to be increased by the gas supply mechanism that supplies gas to the semiconductor manufacturing apparatus when process condition information is input, information regarding the pressure to be increased by the gas supply mechanism is obtained. Using the acquired information regarding the pressure to be increased by the gas supply mechanism, the gas supply mechanism performs processing related to its control. A program that instructs a computer to perform a process.

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