Plasma treatment device, power supply system, and frequency control method

Abstract

The disclosed plasma treatment device comprises a chamber, a substrate-supporting portion, a high-frequency power supply, and a control unit. The substrate-supporting portion is provided inside the chamber. The high-frequency power supply is configured to supply source high-frequency electric power in order to generate plasma from gas within the chamber. The control unit is configured to set the source frequency of the source high-frequency electric power when the source high-frequency electric power is being supplied alone, in accordance with the extent of reflection of the source high-frequency electric power and the source frequency when the source high-frequency electric power has been supplied alone previously, such that the extent of reflection of the source high-frequency electric power is minimized.

Description

Plasma processing apparatus, power supply system, and frequency control method

[0001] SUMMARY Exemplary embodiments of the present disclosure relate to a plasma processing apparatus, a power supply system, and a frequency control method.

[0002] A plasma processing apparatus is used in plasma processing of a substrate. The plasma processing apparatus generates plasma from a gas in a chamber by supplying a source high frequency power. The plasma processing apparatus uses a bias high frequency power to attract ions from the plasma generated in the chamber to the substrate. Patent Document 1 listed below discloses a plasma processing apparatus that modulates the power level and frequency of the bias high frequency power.

[0003] Japanese Patent Application Laid-Open No. 2009-246091

[0004] The present disclosure provides a technique for reducing the degree of reflection of source high frequency power when the source high frequency power is supplied alone.

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, a radio frequency power supply, and a controller. The substrate support is disposed within the chamber. The radio frequency power supply is configured to supply source radio frequency power to generate plasma from a gas within the chamber. The controller is configured to set a source frequency of the source radio frequency power when the source radio frequency power is supplied alone, in accordance with the source frequency when the source radio frequency power was previously supplied alone and the degree of reflection of the source radio frequency power, so as to suppress the degree of reflection of the source radio frequency power.

[0006] According to one exemplary embodiment, it is possible to reduce the degree of reflection of source high frequency power in a state where source high frequency power is supplied alone.

[0007] A more complete understanding of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which:

[0008] FIG. 1 is a block diagram of a computer-based system that functions as a controller for controlling processing performed in an embodiment of the present disclosure; FIG. 2 is a diagram for explaining an example configuration of a plasma processing system; FIG. 3 is a diagram for explaining an example configuration of a capacitively coupled plasma processing apparatus; FIG. 4 is an example timing chart related to a plasma processing apparatus according to an exemplary embodiment; FIG. 5 is a flowchart of a frequency control method according to an exemplary embodiment; FIG. 6 is an example timing chart related to a plasma processing apparatus according to another exemplary embodiment; FIG. 7 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment; FIG. 8 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment; FIG. 9 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment; FIG. 10 is a flowchart of a frequency control method according to another exemplary embodiment.

[0009] Various exemplary embodiments are described below.

[0010] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, a radio frequency power supply, and a controller. The substrate support is disposed within the chamber. The radio frequency power supply is configured to supply source radio frequency power to generate plasma from a gas within the chamber. The controller is configured to set a source frequency of the source radio frequency power when the source radio frequency power is supplied alone, in accordance with the source frequency when the source radio frequency power was previously supplied alone and the degree of reflection of the source radio frequency power, so as to suppress the degree of reflection of the source radio frequency power.

[0011] According to one aspect of the present disclosure, a new apparatus and method is disclosed for generating and rapidly stabilizing a plasma using pulsed high frequency (HF) RF.

[0012] In one exemplary embodiment of the present disclosure, the high frequency power source, under the control of the controller, provides pulsed power to generate plasma.

[0013] As used herein, the singular references to elements or steps should be understood as not excluding the plural references unless expressly expressly excluded. Furthermore, references to "one embodiment" of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also have the recited features.

[0014] The control methods and systems described herein may be implemented using computer programming or engineering techniques, including computer software, firmware, hardware, or any combination or subset thereof, and the technical effect may include at least processing a substrate in a plasma processing apparatus using a controller to control pulsed radio frequency (HF) RF in generating a plasma.

[0015] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0016] FIG. 1 is a block diagram of a computer (as a type of circuit) that may implement various control aspects of embodiments of the present disclosure.

[0017] Control aspects of the present disclosure may be embodied as systems, methods, and / or computer program products, which may include a computer-readable storage medium having computer-readable program instructions recorded thereon that cause one or more processors to perform aspects of the embodiments.

[0018] A computer-readable storage medium may be a tangible device capable of storing instructions for use by an instruction execution device (processor). A computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of these devices. While not exhaustive, a more specific list of examples of computer-readable storage media includes each of (and appropriate combinations of) a floppy disk, a hard disk, a solid-state drive (SSD), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash), a static random access memory (SRAM), a compact disk (CD or CD-ROM), a digital versatile disk (DVD), and a memory card or stick. For purposes of this disclosure, a computer-readable storage medium should not be interpreted as a transitory signal itself, such as an electric wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., light pulses through a fiber optic cable), or an electrical signal transmitted over an electrical wire.

[0019] The computer-readable program instructions described in this disclosure can be downloaded from a computer-readable storage medium to a suitable computing device or processing device, or to an external computer or external storage device via a global network (the Internet), a local area network, a wide area network, and / or a wireless network. The network may include copper transmission lines, fiber optics, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface of each computing device or processing device may receive the computer-readable program instructions from the network and transfer the computer-readable program instructions to a computer-readable storage medium internal to the computing device or processing device for storage.

[0020] The computer-readable program instructions for carrying out the operations of the present disclosure may include machine language instructions and / or microcode. The machine language instructions and / or microcode may be compiled or translated from source code written in a combination of one or more programming languages, including assembly language, Basic, Fortran, Java, Python, R, C, C++, C#, or similar programming languages. All of the computer-readable program instructions may be executed on a user's personal computer, notebook computer, tablet, or smartphone, or on a remote computer or computer server, or on a combination of these computing devices. The remote computer or computer server may be connected to the user's device or devices through a computer network, such as a local area network, a wide area network, or a global network (Internet). In some embodiments, to carry out aspects of the present disclosure, electronic circuitry, including programmable logic circuitry, field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), or the like, may execute computer-readable program instructions to configure or customize the electronic circuitry using information from the computer-readable program instructions.

[0021] Aspects of the present disclosure will be described with reference to flowcharts and block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present disclosure. Those skilled in the art will understand that each block of the flowcharts and block diagrams, and combinations of blocks, can be implemented by computer-readable program instructions.

[0022] Computer-readable program instructions that can implement the systems and methods described in this disclosure may be provided to one or more processors (and / or one or more cores within a processor) of a general-purpose computer, special-purpose computer, or other programmable device to produce a machine, whereby the instructions are executed by the processor of the computer or other programmable device to produce a system that performs the functions shown in the flow diagrams and block diagrams of this disclosure. These computer-readable program instructions may be stored on a computer-readable storage medium that can direct a computer, programmable device, or other device to function in a particular way, such that the computer-readable storage medium storing the instructions is an article of manufacture containing instructions that implement aspects of the functionality shown in the flow diagrams and block diagrams of this disclosure.

[0023] The computer-readable program instructions may be loaded into a computer, other programmable apparatus, or other device to cause the computer, other programmable apparatus, or other device to perform a series of operational steps to produce a computer-implemented process, such that the instructions executing on the computer, other programmable apparatus, or other device may perform the functions shown in the flow diagrams and block diagrams of this disclosure.

[0024] 1 is a functional block diagram illustrating a network system 800 including one or more network computers and servers. In one embodiment, the hardware and software environment illustrated in FIG. 1 may provide an exemplary platform for implementing software and / or methods according to the present disclosure.

[0025] 1, network system 800 may include, but is not limited to, a computer 805, a network 810, a remote computer 815, a web server 820, a cloud storage server 825, and a computer server 830. In some embodiments, multiple instances of one or more of the functional blocks shown in FIG.

[0026] 1 shows further details of computer 805. The functional blocks shown in computer 805 are provided only to illustrate example functionality and are not intended to be exhaustive. Although details of remote computer 815, web server 820, cloud storage server 825, and computer server 830 are not shown, these other computers and devices may include functionality similar to that shown for computer 805.

[0027] The computer 805 may be a personal computer (PC), desktop computer, notebook computer, tablet computer, netbook computer, personal digital assistant (PDA), smartphone, or other programmable electronic device capable of communicating with other devices over the network 810.

[0028] Computer 805 may include a processor 835, a bus 837, memory 840, non-volatile storage 845, a network interface 850, a peripherals interface 855, and a display interface 865. Each of these functions may be implemented as a separate electronic subsystem (an integrated circuit chip or combination of chips and associated devices) in some embodiments, while in other embodiments, a combination of functions may be implemented on a single chip (sometimes called a system-on-chip (SoC)).

[0029] Processor 835 may be one or more single-chip or multi-chip microprocessors designed and / or manufactured by Intel Corporation, Advanced Micro Devices, Inc. (AMD), ARM, Apple Computer, etc. Examples of microprocessors include Intel Corporation's Celeron, Pentium, Core i3, Core i5, and Core i7, AMD's Opteron, Phenom, Athlon, Turion, and Ryzen, and ARM's Cortex-A, Cortex-R, and Cortex-M.

[0030] Bus 837 may be a proprietary or industry standard high speed parallel or serial interconnect bus such as ISA, PCI, PCI Express (PCI-e), or AGP.

[0031] Memory 840 and non-volatile storage 845 may be computer-readable storage media. Memory 840 may include suitable volatile storage devices such as dynamic random access memory (DRAM), static random access memory (SRAM), etc. Non-volatile storage 845 may include one or more of a floppy disk, a hard disk, a solid-state drive (SSD), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash), a compact disk (CD or CD-ROM), a digital versatile disk (DVD), and a memory card or memory stick.

[0032] Program 848 may be a collection of machine-readable instructions and / or data that is stored in non-volatile storage 845 and used to create, manage, and control the software functions described and illustrated in detail elsewhere in this disclosure. In some embodiments, memory 840 may be significantly faster than non-volatile storage 845. In such embodiments, program 848 may be transferred from non-volatile storage 845 to memory 840 before execution by processor 835.

[0033] Computer 805 may communicate and interact with other computers over network 810 via network interface 850. Network 810 may be, for example, a local area network (LAN), a wide area network (WAN) such as the Internet, or a combination of the two, and may include wired, wireless, or fiber optic connections. In general, network 810 may be any combination of connections or protocols that support communication between two or more computers or related devices.

[0034] The peripherals interface 855 may enable data input and output to and from other locally connected devices connected to the computer 805. The peripherals interface 855 may provide, for example, a connection to external devices 860. The external devices 860 may include devices such as a keyboard, mouse, keypad, touch screen, and / or other suitable input devices. The external devices 860 may also include portable computer-readable storage media such as thumb drives, portable optical disks, portable magnetic disks, and memory cards. Software and data, e.g., program 848, used to implement embodiments of the present disclosure may be stored on portable computer-readable storage media. In such embodiments, the software may be loaded into non-volatile storage 845 or may be loaded directly into memory 840 via the peripherals interface 855. The peripherals interface 855 may connect to the external devices 860 using industry-standard connections such as RS-232 or Universal Serial Bus (USB).

[0035] Display interface 865 may connect computer 805 to a display 870. In some embodiments, display 870 may be used to present a command line or graphical user interface to a user of computer 805. Display interface 865 may connect to display 870 using one or more proprietary or industry standard connections, such as VGA, DVI, DisplayPort, and HDMI.

[0036] As mentioned above, network interface 850 provides for communication with other computer systems / devices and storage systems / devices external to computer 805. Software programs and data described herein may be downloaded to non-volatile storage 845 via network interface 850 and network 810 from remote computer 815, web server 820, cloud storage server 825, computer server 830, etc. Additionally, systems and methods described in this disclosure may be implemented by one or more computers connected to computer 805 via network interface 850 and network 810. For example, in some embodiments, systems and methods of this disclosure may be implemented by remote computer 815, computer server 830, or a combination of interconnected computers on network 810.

[0037] Data, datasets, and / or databases used in embodiments of the systems and methods described in this disclosure may be stored on or downloaded from remote computers 815, web servers 820, cloud storage servers 825, and computer servers 830.

[0038] As used herein, a circuit may be defined as one or more of the following: an electronic component (e.g., a semiconductor device), multiple components connected directly to each other or via electronic communication, a computer, a network of computer devices, a remote computer, a web server, a cloud storage server, and a computer server. For example, one or more of a computer, a remote computer, a web server, a cloud storage server, and a computer server may each be included in the circuit or may include a circuit as a component thereof. In some embodiments, multiple instances of one or more of these components may be used, in which case each of the multiple instances of one or more of these components may be included in the circuit or may include a circuit. In some embodiments, a circuit represented by a network system may include a serverless computer system corresponding to a virtual set of hardware resources. A circuit represented by a computer may include a personal computer (PC), a desktop computer, a notebook computer, a tablet computer, a netbook computer, a personal digital assistant (PDA), a smartphone, or other programmable device capable of communicating with other devices over a network. A circuit may be a general-purpose computer, a special-purpose computer, or any other programmable device described herein having one or more processors. Each processor may be one or more single-chip or multi-chip microprocessors. A processor, having transistors and other circuitry, is considered a processing circuit or circuitry that may implement the systems and methods of the present disclosure based on computer-readable program instructions provided to one or more processors (and / or one or more cores within a processor) of one or more general-purpose computers, special-purpose computers, or other programmable devices described herein to cause the machine to implement the systems and methods of the present disclosure, such that the instructions, when executed by one or more processors of a programmable device that is included in the circuitry or includes the circuitry, cause the system to implement the functions identified in the flow diagrams and block diagrams of the present disclosure.Alternatively, a circuit may be a pre-programmed configuration such as a programmable logic device, dedicated integrated circuit, or the like, and is considered a circuit whether used alone or in combination with other programmable or pre-programmed circuits.

[0039] FIG. 2 is a diagram illustrating an example configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0040] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma generated in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Also, various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators.

[0041] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described in this disclosure. The controller 2 may be configured to control each element of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1. The controller 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on programs stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0042] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 3 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0043] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply system 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The sidewall 10a is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0044] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W and an annular region (ring support surface) 111b for supporting the ring assembly 112. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. In one embodiment, the main body 111 includes a base 111e and an electrostatic chuck 111c. The base 111e includes a conductive member. The conductive member of the base 111e functions as a lower electrode. The electrostatic chuck 111c is disposed on the base 111e. The upper surface of the electrostatic chuck 111c has a substrate support surface 111a. The ring assembly 112 includes one or more annular members, at least one of which is an edge ring. Although not shown, the substrate support 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 111c, the ring assembly 112, and the substrate W 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. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a.

[0045] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes a conductive member. The conductive member of the showerhead 13 functions as an upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0046] The gas supply unit 20 may include one or more gas sources 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply one or more process gases from the corresponding gas sources 21 to the showerhead 13 via the corresponding flow controllers 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices that modulate or pulse the flow rate of one or more process gases.

[0047] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0048] The plasma processing apparatus 1 further includes a power supply system 30. The power supply system 30 includes a high-frequency power supply 31 and a control unit 30c. The power supply system 30 may further include a bias power supply 32. The power supply system 30 may further include one or more sensors 31s.

[0049] The RF power supply 31 is configured to generate a source RF power HF to generate a plasma in the chamber (plasma processing chamber 10). The source RF power HF has a source frequency f Ｓ The source frequency f Ｓ is, for example, a frequency in the range of 13 MHz to 200 MHz. Ｓ may be set to 27 MHz, 40.68 MHz, 60 MHz, or 100 MHz. The power level of the source high frequency power HF is, for example, 500 W or more and 20 kW or less.

[0050] In one embodiment, the high-frequency power supply 31 may include a high-frequency signal generator 31g and an amplifier 31a. The high-frequency signal generator 31g generates a high-frequency signal. The amplifier 31a amplifies the high-frequency signal input from the high-frequency signal generator 31g to generate source high-frequency power HF and output the source high-frequency power HF. The high-frequency signal generator 31g may be configured with a programmable processor or a programmable logic device such as an FPGA. A D / A converter may be connected between the high-frequency signal generator 31g and the amplifier 31a.

[0051] The high-frequency power supply 31 is connected to the high-frequency electrode via a matching circuit 31m. In one embodiment, the base 111e constitutes the high-frequency electrode. In another embodiment, the high-frequency electrode may be an electrode provided in the electrostatic chuck 111c. The high-frequency electrode may be a common electrode with a bias electrode, which will be described later. Alternatively, the high-frequency electrode may be an upper electrode. The matching circuit 31m includes a matching circuit. The matching circuit of the matching circuit 31m has a variable impedance. The matching circuit of the matching circuit 31m is controlled by the control unit 30c. The impedance of the matching circuit of the matching circuit 31m is adjusted so as to match the impedance on the load side of the high-frequency power supply 31 to the output impedance of the high-frequency power supply 31.

[0052] One or more sensors 31s may be connected between the high-frequency power supply 31 and the matching box 31m. One or more sensors 31s may be connected between the matching box 31m and the high-frequency electrode. For example, one or more sensors 31s may be connected between the bias electrode and a junction of an electrical path extending from the matching box 31m toward the bias electrode and an electrical path extending from a matching box 32m (described later) toward the bias electrode. Alternatively, one or more sensors 31s may be connected between the junction and the matching box 31m. Note that one or more sensors 31s may be sensors separate from the matching box 31m or may be part of the matching box 31m.

[0053] The one or more sensors 31s may include a directional coupler configured to detect the power level of a reflected wave of the source high frequency power HF returned from the load of the high frequency power supply 31 and notify the control unit 30c of the detected power level of the reflected wave.

[0054] The one or more sensors 31s may also include a VI sensor. The VI sensor detects the voltage V of the source RF power. ＨＦ and current I ＨＦ Detects the voltage V ＨＦ and current I ＨＦ The impedance Z of the load side of the high frequency power supply 31 Ｌ The VI sensor is configured to determine the voltage V ＨＦ and current I ＨＦ The phase difference between the first and second signals may be determined.

[0055] The bias power supply 32 is electrically connected to the bias electrode. In one embodiment, the base 111e constitutes the bias electrode. In another embodiment, the bias electrode may be an electrode provided in the electrostatic chuck 111c. The bias power supply 32 is configured to apply an electric bias EB (or bias energy) to the bias electrode. The bias power supply 32 may also be configured to apply pulses of the electric bias EB to the bias electrode. In this case, the bias power supply 32 may specify the timing of each of a plurality of pulses by a signal provided from a pulse controller 34. Note that the control unit 2 may function as the pulse controller 34.

[0056] The electric bias EB has a waveform period. That is, the electric bias EB is periodically applied to the bias electrode at a time interval of the waveform period. The waveform period of the electric bias EB is the shortest period of the waveform of the electric bias EB and has a time length that is the reciprocal of the bias frequency of the electric bias EB. The bias frequency may be smaller than the source frequency. The bias frequency may be 100 kHz or more and 28 MHz or less, for example, 400 kHz or 3.2 MHz.

[0057] In one embodiment, the electrical bias EB may be bias radio frequency power having a bias frequency. In this case, the bias power supply 32 is connected to the bias electrode via a matching device 32m. The matching device 32m includes a matching circuit. The matching circuit of the matching device 32m has a variable impedance. The matching circuit of the matching device 32m is controlled by the control unit 30c. The impedance of the matching circuit of the matching device 32m is adjusted so as to match the impedance on the load side of the bias power supply 32 to the output impedance of the bias power supply 32. The power level of the bias radio frequency power may be 500 W or more and 50 kW or less.

[0058] In another embodiment, the electric bias EB may include a voltage pulse periodically applied to the bias electrode at a time interval of a waveform period. The voltage pulse may be a negative voltage pulse or a negative DC voltage pulse (a pulse generated by generating a negative DC voltage waveform), or may be another voltage pulse. The voltage pulse may have a waveform such as a triangular wave or a square wave. The voltage pulse may have any other pulse waveform. When a voltage pulse is used as the electric bias EB, the plasma processing apparatus 1 does not include the matching unit 32m.

[0059] The bias power supply 32 may include a signal generator 32g and an amplifier 32a. The signal generator 32g generates a signal for generating an electric bias EB from the signal generator 32g. The amplifier 32a generates the electric bias EB by amplifying the signal input from the signal generator 32g, and supplies the generated electric bias EB to the bias electrode. The signal generator 32g may be configured from a programmable processor or a programmable logic device such as an FPGA. A D / A converter may be connected between the signal generator 32g and the amplifier 32a.

[0060] The bias power supply 32 is synchronized with the high frequency power supply 31. A synchronization signal used for this purpose may be provided from the bias power supply 32 to the high frequency power supply 31. Alternatively, the synchronization signal may be provided from the high frequency power supply 31 to the bias power supply 32. Alternatively, the synchronization signal may be provided to the high frequency power supply 31 and the bias power supply 32 from another device such as the control unit 30c.

[0061] The control unit 30c is configured to control the high-frequency power supply 31. The control unit 30c may be configured with a processor such as a CPU. The control unit 30c may be part of the matching device 31m, may be part of the high-frequency power supply 31, or may be a control unit separate from the matching device 31m and the high-frequency power supply 31. Alternatively, the control unit 2 may also function as the control unit 30c.

[0062] In various embodiments, the control unit 30c controls the period P during which the source high frequency power HF is supplied alone to generate plasma in the chamber 10. ＨＯ Source frequency f during the single supply period ｓ The control unit 30c sets the period P ＨＯ The source frequency f at each time point ｓ is the source frequency f when the source high frequency power HF is supplied alone. Ｓ The period P is set so as to suppress the degree of reflection of the source high frequency power HF depending on the degree of reflection of the source high frequency power HF. ＨＯ is a period in which the electric bias EB is not supplied and the source high frequency power HF is supplied alone.

[0063] In various embodiments, the degree of reflection may be obtained as the power level of the reflected wave of the source high frequency power HF. The degree of reflection may be obtained as the power level of the forward wave of the source high frequency power HF or the ratio of the power level of the reflected wave of the source high frequency power HF to the set output power level of the source high frequency power HF. Alternatively, the degree of reflection may be obtained as the ratio of the impedance Z Ｌ Alternatively, the degree of reflection may be obtained as a deviation amount of the voltage V ＨＦ and current I ＨＦ Alternatively, the degree of reflection may be obtained as the phase difference between the source frequency f Ｓ Alternatively, the reflectivity may be obtained as a function of the reflectivity of the plasma at the incident light source 31s, or as another quantity representing the degree of alignment of the plasma at the incident light source 31s. In either case, the degree of reflectivity may be obtained by one or more sensors 31s or determined from measurements obtained by one or more sensors 31s.

[0064] Below, period P ＨＯ Source frequency f at Ｓ Various embodiments regarding the setting (or changing) of will be described.

[0065] [First embodiment]

[0066] 4 is a timing chart of an example related to a plasma processing apparatus according to an exemplary embodiment. FIG. 4 shows the source high frequency power HF, the frequency setting method, and the source frequency f Ｓ 4 shows a timing chart of the source high frequency power HF. In FIG. 4, "ON" of the source high frequency power HF indicates that the source high frequency power HF is being supplied, and "OFF" of the source high frequency power HF indicates that the supply of the source high frequency power HF is stopped. In FIG. 4, the frequency setting method is Ｓ In the first embodiment, the frequency setting method includes a sequential feedback process FSB. In the first embodiment, the frequency setting method may further include a start-up process FSA.

[0067] In the first embodiment, a source high frequency power HF is supplied to generate plasma, but an electric bias EB is not used. In the first embodiment, the plasma processing apparatus 1 does not necessarily have to include the bias power supply 32 and the matching box 32m. Also, the plasma processing apparatus 1 does not necessarily have to include the pulse controller 34.

[0068] In the first embodiment, the high frequency power supply 31 operates in the period P ＨＯ The high frequency power supply 31 starts supplying the source high frequency power HF at the start of the period P ＨＯ That is, in the first embodiment, the high frequency power supply 31 continuously supplies the source high frequency power HF during the period P ＨＯ A source of continuous high frequency power HF is provided at

[0069] In the first embodiment, the period P ＨＯ is a number of sub-periods SP, i.e., I sub-periods SP １ , SP ２ , ..., SP Ｉ A plurality of sub-periods SP １ , SP ２ , ..., SP Ｉ is the period P ＨＯ Period P Ｂis divided into I sub-periods SP. The time lengths of the sub-periods SP may be the same as or different from one another. The time length of each of the sub-periods SP may be 10 nsec or more and 10 μsec or less.

[0070] Period P ＨＯ is the start-up period P before the sub-periods SP Ｓ The start-up period P Ｓ The high frequency power supply 31 may include a period for ignition of plasma. Ｓ At the start of the period P Ｂ is the start-up period P Ｓ It may be a period following.

[0071] As shown in FIG. 4, the control unit 30c controls the start-up period P Ｓ Specifically, the control unit 30c performs the start-up process FSA during the start-up period P Ｓ From the start to the end of Ｓ is changed according to the initial frequency set. The initial frequency set is prepared in advance and stored in a storage unit accessible by the control unit 30c. The initial frequency set may be obtained experimentally or may be determined based on past processing results.

[0072] The control unit 30c Ｓ The period P after Ｂ Specifically, the control unit 30c performs the sequential feedback process FSB during the i-th sub-period SP ｉ Source frequency f at Ｓ [i] is the i-th sub-period SP among the multiple sub-periods ｉ the source frequency f in each of the one or more subperiods prior to Ｓ Depending on the degree of reflection of the source high frequency power HF, the sub-period SP ｉ The setting is made so as to suppress the degree of reflection of the source high frequency power HF at

[0073] In one embodiment, the sub-period SP ｉ One or more subperiods before the subperiod SP ｉーｖ (first sub-period) and sub-period SPｉーｕ (second sub-period). Here, v and u are integers equal to or greater than 1, and v is greater than u. v may be 2, and u may be 1. Note that if the duration of each of the multiple sub-periods SP is short, u may be 20 or greater to reduce the calculation load. For example, if the duration of each of the multiple sub-periods SP is 50 ns, then the sub-periods SP ｉ is the sub-period SP ｉーｕ This is the period 1 μs after the

[0074] In the sequential feedback process FSB, the control unit 30c ｉーｖ Source frequency f at Ｓ [iv] to sub-period SP ｉーｕ Source frequency f at Ｓ Change to [iu] and sub-period SP ｉーｖ The degree of reflection of the source high frequency power HF in the sub-period SP ｉーｕ and the change in the degree of reflection of the source high frequency power HF in the sub-period SP ｉ To suppress the degree of reflection of the source high frequency power HF at the source frequency f Ｓ [i] may be set.

[0075] For example, the sub-period SP ｉーｖ The degree of reflection of the source high frequency power HF in the sub-period SP ｉーｕ If the change in the degree of reflection of the source high frequency power HF at the source frequency f is a decrease in the degree of reflection, the control unit 30c Ｓ [i-v] to source frequency f Ｓ The change in the same direction as the change in [i-u] is the source frequency f Ｓ The frequency given to [i-u] is the source frequency f Ｓ [i]. Sub-period SP ｉーｖ The degree of reflection of the source high frequency power HF in the sub-period SP ｉーｕ If the change in the degree of reflection of the source high frequency power HF at the source frequency f is an increase in the degree of reflection, the control unit 30c Ｓ [i-v] to source frequency f Ｓ The change in the direction opposite to the change to [i-u] is the source frequency fＳ The frequency given to [i-u] is the source frequency f Ｓ Set it as [i].

[0076] According to the first embodiment, the degree of reflection of the source high frequency power HF is reduced during a period in which the source high frequency power HF is supplied independently and continuously. Furthermore, according to the first embodiment, the rise time until the plasma is stabilized can be accelerated. Furthermore, according to the first embodiment, abnormal discharge of the plasma can be suppressed. Furthermore, according to the first embodiment, the source frequency f Ｓ Since the reflection is suppressed by adjusting the frequency, the operation of the variable capacitor of the matching circuit 31m is reduced, and the life of the variable capacitor can be improved.

[0077] Reference is now made to Fig. 5, which is a flow chart of a frequency control method according to one exemplary embodiment. The frequency control method shown in Fig. 5 (hereinafter referred to as "method MTA") can be performed in a state in which a substrate W is placed on a substrate support 11 in a chamber 10. In method MTA, a plasma process can be performed on the substrate W. The plasma process in method MTA may include plasma etching of the substrate W.

[0078] The method MTA begins with step STAa, in which source high frequency power HF is supplied from the high frequency power supply 31 to generate plasma from the gas in the chamber 10. In the first embodiment, the source high frequency power HF is supplied continuously, i.e., a continuous wave of the source high frequency power HF is supplied.

[0079] The method MTA may further include a step STAb. Ｓ In the step STAb, the start-up process FSA described above in relation to the first embodiment is performed.

[0080] In the step STAc, the sequential feedback process FSB described above in relation to the first embodiment is performed. That is, in the step STAc, the source frequency f Ｓ However, when the source high frequency power HF is supplied alone, the source frequency f Ｓand is set so as to suppress the degree of reflection of the source high frequency power HF in accordance with the degree of reflection of the source high frequency power HF.

[0081] Second Embodiment

[0082] 6 is a timing chart of an example related to a plasma processing apparatus according to another exemplary embodiment. FIG. 6 shows the timing chart of the source high frequency power HF, the electrical bias EB, the frequency setting method, the source frequency f Ｓ , and a timing chart of the degree of reflection RD. In FIG. 6, "HIGH" of the source high frequency power HF indicates that the power level of the source high frequency power HF is higher than the power level of the source high frequency power HF indicated by "LOW". In FIG. 6, "OFF" of the source high frequency power HF indicates that the supply of the source high frequency power HF is stopped. In FIG. 6, "ON" of the electric bias EB indicates that the electric bias EB is being supplied, and "OFF" of the electric bias EB indicates that the supply of the electric bias EB is stopped. In FIG. 6, the frequency setting method is Ｓ In the second embodiment, the frequency setting method includes a ramp-up process FSA, a sequential feedback process FSB, and a pulse-to-pulse feedback process FSC.

[0083] In the second embodiment, the high frequency power supply 31 generates a plurality of pulse periods PC (i.e., pulse periods PC １ , PC ２ , ...), the plurality of pulse periods PC appear in sequence. Each of the plurality of pulse periods PC has a period P ＢＯ and P ＨＯ Includes the period P ＨＯ is one of two periods in each of the plurality of pulse periods PC, and the period P ＢＯ is the other period.

[0084] In the second embodiment, the high frequency power supply 31 operates in a period P ＨＯThe high frequency power supply 31 supplies the source high frequency power HF whose power level is indicated as "LOW" during the period P ＢＯ In other words, in each of the plurality of pulse periods PC, a source high frequency power HF is supplied whose power level is indicated as "HIGH." ＨＯ The power level of the source high frequency power HF in the period P ＢＯ The power level of the source high frequency power HF in each of the plurality of pulse periods PC is lower than the power level of the source high frequency power HF in each of the plurality of pulse periods PC. ＨＯ The power level of the source high frequency power HF in the period P ＢＯ The power level may be higher than the power level of the source high frequency power HF at

[0085] In the second embodiment, the bias power supply 32 is ＨＯ The supply of the electric bias EB to the substrate support 11 is stopped during the period P ＢＯ An electric bias EB is supplied to the substrate support 11 during the period P ＨＯ is the source RF power without supplying an electrical bias EB. ＨＦ is the sole supply period in which the supply is made alone.

[0086] Period P ＨＯ , that is, the single supply period is the start-up period P Ｓ Including the start-up period P Ｓ may include the period of plasma ignition. ＨＯ is the period P Ｂ The start-up period P Ｓ is the period P Ｂ The period before period P Ｂ is the start-up period P Ｓ It may be a period following.

[0087] As shown in FIG. 6, the control unit 30c controls at least the first pulse period PC １ A rise period P in each of one or more consecutive pulse periods including ＳSpecifically, the control unit 30c performs the start-up process FSA during the start-up period P Ｓ From the start to the end of Ｓ is changed according to the initial frequency set. The initial frequency set is prepared in advance and stored in a storage unit accessible by the control unit 30c. The initial frequency set may be obtained experimentally or may be determined based on past processing results. Note that the initial pulse period PC １ The number of one or more consecutive pulse periods including may be 2 or more and 20 or less.

[0088] First pulse period PC １ The rise period P of each pulse period PC after one or more consecutive pulse periods including Ｓ In this case, the control unit 30c performs inter-pulse feedback processing FSC. Specifically, the control unit 30c performs inter-pulse feedback processing FSC based on the pulse period PC ｎ Start-up period P Ｓ The source frequency f at each phase in Ｓ , the pulse period PC ｎ－ｑ the source frequency f in phase with Ｓ From pulse period PC ｎ－ｐ the source frequency f in phase with Ｓ and the pulse period PC ｎ－ｑ The degree of reflection of the source high frequency power HF in the same phase within the pulse period PC ｎ－ｐ and the pulse period PC in response to the change in the degree of reflection of the source high frequency power HF in the same phase within ｎ The pulse period PC is set to suppress the degree of reflection of the source high frequency power HF in the same phase within the ｎ The phase in the pulse period PC ｎ The pulse period PC is determined by the elapsed time from the start of ｎ Therefore, the same phase in a plurality of pulse periods is a time point that has the same elapsed time from the start of the corresponding pulse period. ｎ , pulse period PC ｎ－ｑ , pulse period PC ｎ－ｐare the n-th pulse period, the (nq)-th pulse period, and the (np)-th pulse period among the plurality of pulse periods PC. q and p are integers equal to or greater than 1, and q is greater than p. For example, q is 2 and p is 1.

[0089] Here, the pulse period PC ｎ Start-up period P Ｓ The phase in ｍ The phase α ｍ is the start-up period P Ｓ In one example, the pulse period PC ｎーｑ Start-up period P Ｓ Phase α within ｍ The degree of reflection of the source high frequency power HF at the pulse period PC ｎーｐ Start-up period P Ｓ Phase α within ｍ If the change in the degree of reflection of the source high frequency power HF at the source frequency f is a decrease in the degree of reflection, the control unit 30c Ｓ [n-q, α ｍ ] to the source frequency f Ｓ [n-p, α ｍ ] is a change in the same direction as the change in source frequency f Ｓ [n-p, α ｍ ] is the source frequency f Ｓ [n, α ｍ ]. Note that the source frequency f Ｓ [n, α ｍ ] is the pulse period PC ｎ Start-up period P Ｓ Phase α within ｍ Source frequency f at Ｓ The pulse period PC ｎーｑ Start-up period P Ｓ Phase α within ｍ The degree of reflection of the source high frequency power HF at the pulse period PC ｎーｐ Start-up period P Ｓ Phase α within ｍ If the change in the degree of reflection of the source high frequency power HF at the source frequency f is an increase in the degree of reflection, the control unit 30c Ｓ [n-q, α ｍ] to the source frequency f Ｓ [n-p, α ｍ ] and the change in the opposite direction to the source frequency f Ｓ [n-p, α ｍ ] is the source frequency f Ｓ [n, α ｍ ].

[0090] In the second embodiment, the control unit 30c controls the period P Ｂ The above-mentioned sequential feedback process FSB may be performed during the period P Ｂ is the period P ＨＯ Alternatively, the period P Ｂ is the start-up period P Ｓ In the above, the process may start when the change in the degree of reflection becomes equal to or less than a specified value.

[0091] In the second embodiment, the first pulse period PC １ The rise period P in each of one or more consecutive pulse periods including Ｓ and the rise period P in each pulse period after the one or more consecutive pulse periods. Ｓ The time lengths may be the same as each other or may be different from each other.

[0092] In a modification of the second embodiment, the control unit 30c controls the period P ＨＯ Alternatively, as shown in FIG. 7, the control unit 30c may perform the start-up process FSA first, then the inter-pulse feedback process FSC, and then the sequential feedback process FSB. ＨＯ In this case, only the inter-pulse feedback process FSC may be performed. In this case, the period P ＨＯ The source frequency f Ｓ may be changed according to a different initial frequency set.

[0093] In the second embodiment, the period P ＨＯ is divided into a plurality of sub-periods, and each of the plurality of sub-periods is called a period P ＨＯ The above-described inter-pulse feedback process FSC may be applied to each phase within the plurality of sub-periods. The time length of each of the plurality of sub-periods is, for example, 10 nsec or more and 10 μsec or less. Note that in each of the plurality of sub-periods, the source frequency f ｓ may be set to a single frequency or to multiple frequencies.

[0094] In the second embodiment, the period P ＨＯ The power level of the source high frequency power HF in the period P ＨＯ In this case, the period P ＨＯ may be divided into a plurality of divided periods for each power level of the source high frequency power HF, and the start-up process FSA, the inter-pulse feedback process FSC, and the sequential feedback process FSB may be performed in each of the plurality of divided periods.

[0095] Another modification of the second embodiment will be described below with reference to Fig. 8. As shown in Fig. 8, in this modification of the second embodiment, the period P ＨＯ The power level of the source high frequency power HF in the period P ＨＯ For example, the period P ＨＯ may include one or more periods in which the power level of the source high frequency power HF has a level indicated as "LOW" and one or more periods in which the power level has a level indicated as "OFF". The level indicated as "LOW" is lower than the level indicated as "HIGH". The level indicated as "OFF" is zero. In other words, in the period having the level indicated as "OFF", the supply of the source high frequency power HF is stopped. In the example shown in FIG. 8, the period P ＨＯ The period including the start point of the period P ＳIn two periods including the start and end points, the source high frequency power having a level indicated by "LOW" is supplied, and in the period between these two periods, the supply of the source high frequency power HF is stopped.

[0096] In another variation of the second embodiment as shown in FIG. 8, the period P ＨＯ In this case, only the pulse-to-pulse feedback process FSC may be performed. ＨＯ In the period including the start point of the period P ＨＯ In this case, only the inter-pulse feedback process FSC may be performed in the other periods within the plurality of pulse periods PC. ＨＯ The source frequency f Ｓ may be changed according to a different initial frequency set.

[0097] According to the second embodiment, the period P during which the source high frequency power HF is supplied alone ＨＯ In the second embodiment, the degree of reflection of the source high frequency power HF is reduced. Furthermore, according to the second embodiment, the rise time until the plasma is stabilized can be increased. Furthermore, according to the second embodiment, abnormal discharge of the plasma can be suppressed. Furthermore, according to the second embodiment, the reproducibility of the effective power level (load power level) of the source high frequency power HF is improved. For example, in the period P ＨＯ In the second embodiment, when the power level of the source high frequency power HF is changed to a plurality of power levels, the reproducibility of the effective power level (load power level) corresponding to each power level is improved. Ｓ Since the reflection is suppressed by adjusting the frequency, the operation of the variable capacitor of the matching circuit 31m is reduced, and the life of the variable capacitor can be improved.

[0098] [Third embodiment]

[0099] Referring to FIG. 9, the source frequency f Ｓ9 is a timing chart of an example related to a plasma processing apparatus according to yet another exemplary embodiment. FIG. 9 shows the source high frequency power HF, the electrical bias EB, the frequency setting method, the source frequency f in the third embodiment. Ｓ 9 shows a timing chart of the degree of reflection RD and the source high frequency power HF. In FIG. 9, "ON" of the source high frequency power HF indicates that the source high frequency power HF is being supplied, and "OFF" of the source high frequency power HF indicates that the supply of the source high frequency power HF is stopped. In FIG. 9, "ON" of the electric bias EB indicates that the electric bias EB is being supplied, and "OFF" of the electric bias EB indicates that the supply of the electric bias EB is stopped. In FIG. 9, the frequency setting method is Ｓ In the third embodiment, the frequency setting method includes a rise process FSA, a sequential feedback process FSB, and a pulse-to-pulse feedback process FSC. The third embodiment will be described below from the viewpoint of the differences between the second and third embodiments.

[0100] In the third embodiment, similarly to the second embodiment, the high frequency power supply 31 is ＨＯ On the other hand, in the third embodiment, unlike the second embodiment, the high frequency power supply 31 supplies the source high frequency power HF during the period P ＢＯ That is, in the third embodiment, the high frequency power supply 31 stops supplying the source high frequency power HF during the period in which the electric bias EB is being supplied.

[0101] The period P in the third embodiment ＨＯ Source frequency f Ｓ The process of setting the period P ＨＯ Source frequency f at Ｓ The process is similar to the setting of

[0102] In the third embodiment, the first pulse period PC １ The rise period P in each of one or more consecutive pulse periods includingＳ and the rise period P in each pulse period after the one or more consecutive pulse periods. Ｓ The time lengths may be the same as each other or may be different from each other.

[0103] In a modification of the third embodiment, the control unit 30c controls the period P ＨＯ Alternatively, as shown in FIG. 10, the control unit 30c may perform the start-up process FSA first, then the inter-pulse feedback process FSC, and then the sequential feedback process FSB. ＨＯ In this case, only the inter-pulse feedback process FSC may be performed. In this case, the period P ＨＯ The source frequency f Ｓ may be changed according to a different initial frequency set.

[0104] In the third embodiment, the period P ＨＯ is divided into a plurality of sub-periods, and each of the plurality of sub-periods is called a period P ＨＯ The above-described inter-pulse feedback process FSC may be applied to each phase within the plurality of sub-periods. The time length of each of the plurality of sub-periods is, for example, 10 nsec or more and 10 μsec or less. Note that in each of the plurality of sub-periods, the source frequency f ｓ may be set to a single frequency or to multiple frequencies.

[0105] In the third embodiment, the period P ＨＯ The power level of the source high frequency power HF in the period P ＨＯ In this case, the period P ＨＯ may be divided into a plurality of divided periods for each power level of the source high frequency power HF, and the start-up process FSA, the inter-pulse feedback process FSC, and the sequential feedback process FSB may be performed in each of the plurality of divided periods.

[0106] Hereinafter, the frequency control methods according to the second and third embodiments will be described with reference to Fig. 11. Fig. 11 is a flow chart of a frequency control method according to another exemplary embodiment. Fig. 11 shows a frequency control method according to the second and third embodiments, in which the period P ＨＯ 11 shows the flow of a frequency control method in the chamber 10. The frequency control method shown in FIG. 11 (hereinafter referred to as "method MTB") can be performed in a state where a substrate W is placed on a substrate support 11 in the chamber 10. In method MTB, a plasma process can be performed on the substrate W. The plasma process in method MTB may include plasma etching of the substrate W.

[0107] The method MTB begins with step STBa, which includes a period P ＨＯ In the step STBa, a pulse of source high frequency power HF is supplied from the high frequency power supply 31 to generate plasma from the gas in the chamber 10 .

[0108] The method MTB may further include a step STBb, which is a step of detecting a rise period P in each of one or more consecutive pulse periods including a first pulse period among the plurality of pulse periods PC. Ｓ In the step STBb, the above-described start-up process FSA is performed.

[0109] In the step STBc, the above-mentioned inter-pulse feedback process FSC is performed. The inter-pulse feedback process FSC is performed by adjusting the rise period P in each pulse period after one or more consecutive pulse periods including the first pulse period among the plurality of pulse periods PC. Ｓ Alternatively, the inter-pulse feedback process FSC may be performed during each period P of the plurality of pulse periods PC. ＨＯ Alternatively, the inter-pulse feedback process FSC may be performed during each period P of the plurality of pulse periods PC. ＨＯ This may be performed after the start-up process FSA within the system.

[0110] The method MTB may further include a step STBd. In the step STBd, the above-mentioned sequential feedback process FSB is performed. Note that the sequential feedback process FSB is performed during a period P ＨＯ In the start-up period P Ｓ Alternatively, the sequential feedback process FSB may be performed after a period P ＨＯ In this case, the feedback process FSA may be performed after the pulse-to-pulse feedback process FSC that is performed following the start-up process FSA.

[0111] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0112] For example, in another embodiment, the plasma processing apparatus may be an inductively coupled plasma processing apparatus, in which the source high frequency power HF is supplied to an antenna.

[0113] Various exemplary embodiments included in the present disclosure are now described in [E1] to [E14] below.

[0114] [E1] A plasma processing apparatus comprising: a chamber; a substrate support section provided within the chamber; a radio frequency power supply configured to supply source radio frequency power to generate plasma from a gas within the chamber; and a control section, wherein the control section is configured to set a source frequency of the source radio frequency power when the source radio frequency power is supplied alone, in accordance with the source frequency and the degree of reflection of the source radio frequency power when the source radio frequency power was previously supplied alone, so as to suppress the degree of reflection of the source radio frequency power.

[0115] [E2] The plasma processing apparatus of E1, wherein the high frequency power supply is configured to continuously supply the source high frequency power within an individual supply period, the individual supply period including a plurality of sub-periods, and the control unit is configured to set the source frequency in an i-th sub-period of the plurality of sub-periods so as to suppress a degree of reflection of the source high frequency power according to the source frequency and a degree of reflection of the source high frequency power in each of one or more sub-periods prior to the i-th sub-period of the plurality of sub-periods.

[0116] [E3] The plasma processing apparatus of E2, wherein the one or more sub-periods include a first sub-period and a second sub-period following the first sub-period, and the control unit is configured to: set the source frequency in the second sub-period to a frequency different from the source frequency in the first sub-period; and set the source frequency in the i-th sub-period so as to suppress a degree of reflection of the source high frequency power in accordance with a change from the source frequency in the first sub-period to the source frequency in the second sub-period and a change from a degree of reflection of the source high frequency power in the first sub-period to a degree of reflection of the source high frequency power in the second sub-period.

[0117] [E4] The plasma processing apparatus according to E2 or E3, wherein the single supply period further includes a ramp-up period before the plurality of sub-periods, the ramp-up period including a start point of the single supply period, and the control unit is configured to change the source frequency according to an initial frequency set during a period from the start to the end of the ramp-up period.

[0118] [E5] The plasma processing apparatus according to any one of E2 to E4, further comprising a bias power supply electrically coupled to the substrate support and configured to supply an electric bias for ion attraction to the substrate support, and the independently supplied period is a period during which the electric bias from the bias power supply is not supplied to the substrate support.

[0119] [E6] The plasma processing apparatus further includes a bias power supply electrically coupled to the substrate support and configured to supply an electric bias for ion attraction to the substrate support, wherein the high frequency power supply is configured to supply the source high frequency power during one of two periods in each of a plurality of pulse periods, and the bias power supply is configured to stop supplying the electric bias to the substrate support during the one of the two periods in each of the plurality of pulse periods and supply the electric bias to the substrate support during the other of the two periods, wherein the one period includes a start-up period including a start point thereof, the control unit is configured to set the source frequency at each phase in the rise period within the one period in an n-th pulse period among the plurality of pulse periods so as to suppress a degree of reflection of the source radio frequency power in accordance with a change from the source frequency at the same phase in an (n-q)-th pulse period among the plurality of pulse periods to the source frequency at the same phase in an (n-p)-th pulse period among the plurality of pulse periods, and a change from a degree of reflection of the source radio frequency power at the same phase in the (n-q)-th pulse period to a degree of reflection of the source radio frequency power at the same phase in the (n-p)-th pulse period, wherein q and p are integers of 1 or greater that satisfy q>p.

[0120] [E7] The plasma processing apparatus according to E6, wherein the control unit is configured to change the source frequency according to an initial frequency set during a period from the start to the end of the ramp-up period in each of one or more consecutive pulse periods including at least a first pulse period among the plurality of pulse periods.

[0121] [E8] The plasma processing apparatus according to E6 or E7, wherein each of the plurality of pulse periods includes a plurality of sub-periods after the start-up period, and the control unit is configured to set the source frequency in an i-th sub-period of the plurality of sub-periods of each of the plurality of pulse periods so as to suppress a degree of reflection of the source high frequency power according to the source frequency and a degree of reflection of the source high frequency power in each of one or more sub-periods prior to the i-th sub-period of the plurality of sub-periods.

[0122] [E9] The plasma processing apparatus according to E8, wherein the one or more sub-periods include a first sub-period and a second sub-period following the first sub-period, and the control unit is configured to: set the source frequency in the second sub-period to a frequency different from the source frequency in the first sub-period; and set the source frequency in the i-th sub-period so as to suppress a degree of reflection of the source high frequency power in accordance with a change from the source frequency in the first sub-period to the source frequency in the second sub-period and a change from a degree of reflection of the source high frequency power in the first sub-period to a degree of reflection of the source high frequency power in the second sub-period.

[0123] [E10] The plasma processing apparatus according to any one of E6 to E9, wherein the high frequency power supply is configured to stop supplying the source high frequency power during the other period.

[0124] [E11] The plasma processing apparatus according to any one of E6 to E9, wherein the high frequency power supply is configured to supply the source high frequency power during the other period.

[0125] [E12] The plasma processing apparatus according to E11, wherein the power level of the source high frequency power in the one period is lower than the power level of the source high frequency power in the other period.

[0126] [E13] A power supply system comprising: a high frequency power supply configured to supply source high frequency power to generate plasma from a gas in a chamber of a plasma processing apparatus; and a control unit, wherein the control unit is configured to set the source frequency of the source high frequency power when the source high frequency power is supplied alone, so as to suppress the degree of reflection of the source high frequency power, depending on the source frequency and the degree of reflection of the source high frequency power when the source high frequency power was previously supplied alone.

[0127] [E14] A frequency control method comprising: (a) a step of supplying source high frequency power from a high frequency power source to generate plasma from a gas in a chamber of a plasma processing apparatus; and (b) a step of setting, in (a), a source frequency of the source high frequency power when the source high frequency power is supplied alone, so as to suppress the degree of reflection of the source high frequency power in accordance with the source frequency when the source high frequency power was previously supplied alone and the degree of reflection of the source high frequency power.

[0128] Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

[0129] 1... plasma processing apparatus, 10... chamber, 11... substrate support part, 31... high frequency power supply, 32... bias power supply, 30c... control part.

Claims

1. A chamber; a substrate support disposed within the chamber; a radio frequency power source configured to provide radio frequency power to generate a plasma from a gas in the chamber; A control unit; Equipped with the high frequency power supply is configured to continuously supply the high frequency power during a single supply period included in each of a plurality of repetition periods; the control unit is configured to set a frequency of the high frequency power in an i-th sub-period among a plurality of sub-periods in the individual supply period in each of the plurality of repetition periods, in accordance with the frequency of the high frequency power and a degree of reflection of the high frequency power in each of one or more sub-periods preceding the i-th sub-period among the plurality of sub-periods in the individual supply period in each of the plurality of repetition periods, so as to suppress a degree of reflection of the high frequency power. Plasma processing equipment.

2. the one or more subperiods include a first subperiod and a second subperiod subsequent to the first subperiod; The control unit is setting the frequency of the high frequency power in the second sub-period to a frequency different from the frequency of the high frequency power in the first sub-period; setting the frequency of the high frequency power in the i-th sub-period so as to suppress a degree of reflection of the high frequency power in accordance with a change from the frequency of the high frequency power in the first sub-period to the frequency of the high frequency power in the second sub-period and a change from a degree of reflection of the high frequency power in the first sub-period to a degree of reflection of the high frequency power in the second sub-period; 2. The plasma processing apparatus according to claim 1, wherein the plasma processing apparatus is configured as follows.

3. The single supply period further includes a ramp-up period preceding the plurality of sub-periods, 2. The plasma processing apparatus of claim 1, wherein the control unit is configured to set the frequency of the high frequency power at each phase within the start-up period within the individual supply period in an nth repetition period among the multiple repetition periods, in accordance with the frequency of the high frequency power at the same phase within the start-up period within the individual supply period in one or more repetition periods prior to the nth repetition period among the multiple repetition periods, and the degree of reflection of the high frequency power, so as to suppress the degree of reflection of the high frequency power.

4. The control unit is configured to set the frequency of the high frequency power at each phase in the ramp-up period within the individual supply period in the n-th repetition period in accordance with a change from the frequency of the high frequency power at the same phase in the ramp-up period within the individual supply period in the (n-q)-th repetition period among the plurality of repetition periods to the frequency of the high frequency power at the same phase in the ramp-up period within the individual supply period in the (n-p)-th repetition period among the plurality of repetition periods, and a change from a degree of reflection of the high frequency power at the same phase in the ramp-up period within the individual supply period in the (n-q)-th repetition period to a degree of reflection of the high frequency power at the same phase in the ramp-up period within the individual supply period in the (n-p)-th repetition period, wherein q and p are integers equal to or greater than 1 such that q>p. The plasma processing apparatus according to claim 3 .

5. The plasma processing apparatus of claim 3, wherein the control unit is configured to change the frequency of the high-frequency power according to an initial frequency set from the start to the end of the ramp-up period in each of one or more consecutive repetition periods including at least a first repetition period among the plurality of repetition periods.

6. The single supply period further includes a ramp-up period preceding the plurality of sub-periods, The control unit is configured to change the frequency of the high frequency power according to an initial frequency set during a period from a start to an end of the ramp-up period in each of one or more consecutive repetitive periods including at least a first repetitive period among the plurality of repetitive periods. The plasma processing apparatus according to claim 1 .

7. a bias power supply electrically coupled to the substrate support and configured to provide an electrical bias to the substrate support for ion attraction; the single supply period is a period during which the electrical bias from the bias power supply is not supplied to the substrate support; The plasma processing apparatus according to any one of claims 1 to 6.

8. The plasma processing apparatus further comprises a bias power supply electrically coupled to the substrate support and configured to provide an electrical bias to the substrate support for ion attraction; the high frequency power supply is configured to supply the high frequency power in one of two periods included in each of the plurality of repetition periods, the one period being the single supply period; the bias power supply is configured to stop supplying the electrical bias to the substrate support during one of the two periods in each of the plurality of repeating cycles and to supply the electrical bias to the substrate support during the other of the two periods. The plasma processing apparatus according to any one of claims 1 to 6.

9. The plasma processing apparatus according to claim 8 , wherein the high frequency power supply is configured to stop supplying the high frequency power during the other period.

10. The plasma processing apparatus according to claim 8 , wherein the high frequency power supply is configured to supply the high frequency power during the other period.

11. The plasma processing apparatus according to claim 10 , wherein a power level of the high frequency power in the one period is lower than a power level of the high frequency power in the other period.

12. a radio frequency power source configured to provide radio frequency power to generate a plasma from a gas in a chamber of the plasma processing device; A control unit; Equipped with the high frequency power supply is configured to continuously supply the high frequency power during a single supply period included in each of a plurality of repetition periods; the control unit is configured to set a frequency of the high frequency power in an i-th sub-period among a plurality of sub-periods in the individual supply period in each of the plurality of repetition periods, in accordance with the frequency of the high frequency power and a degree of reflection of the high frequency power in each of one or more sub-periods preceding the i-th sub-period among the plurality of sub-periods in the individual supply period in each of the plurality of repetition periods, so as to suppress a degree of reflection of the high frequency power. Power supply system.

13. The single supply period further includes a ramp-up period preceding the plurality of sub-periods, 13. The power supply system of claim 12, wherein the control unit is configured to set the frequency of the high frequency power at each phase within the start-up period in the individual supply period in an n-th repetition period among the multiple repetition periods, in accordance with the frequency of the high frequency power at the same phase within the start-up period in the individual supply period in one or more repetition periods prior to the n-th repetition period among the multiple repetition periods, and a degree of reflection of the high frequency power, so as to suppress a degree of reflection of the high frequency power.

14. The power supply system of claim 13, wherein the control unit is configured to change the frequency of the high-frequency power according to an initial frequency set from the start to the end of the ramp-up period in each of one or more consecutive repetition periods including at least a first repetition period of the plurality of repetition periods.

15. The single supply period further includes a ramp-up period preceding the plurality of sub-periods, The control unit is configured to change the frequency of the high frequency power according to an initial frequency set during a period from a start to an end of the ramp-up period in each of one or more consecutive repetitive periods including at least a first repetitive period among the plurality of repetitive periods.

13. The power system of claim 12.

16. (a) supplying radio frequency power from a radio frequency power source sequentially during a single supply period of each of a plurality of repeating cycles to generate a plasma from a gas within a chamber of a plasma processing device; (b) setting a frequency of the high frequency power in an i-th sub-period among a plurality of sub-periods in the individual supply period in each of the plurality of repetition periods, according to the frequency of the high frequency power and a degree of reflection of the high frequency power in each of one or more sub-periods preceding the i-th sub-period among the plurality of sub-periods in the individual supply period in each of the plurality of repetition periods, so as to suppress a degree of reflection of the high frequency power; A frequency control method comprising:

17. The single supply period further includes a ramp-up period prior to the plurality of sub-periods, setting the frequency of the high frequency power at each phase in the ramp-up period in the individual supply period in an n-th repetitive period among the plurality of repetitive periods in accordance with the frequency of the high frequency power at the same phase in the ramp-up period in the individual supply period in one or more repetitive periods prior to the n-th repetitive period among the plurality of repetitive periods and a degree of reflection of the high frequency power, so as to suppress a degree of reflection of the high frequency power; 17. The frequency control method according to claim 16.

18. A frequency control method as described in claim 17, further comprising a step of changing the frequency of the high frequency power according to an initial frequency set from the start to the end of the ramp-up period in each of one or more consecutive repetition periods including at least a first repetition period of the plurality of repetition periods.

19. The single supply period further includes a ramp-up period prior to the plurality of sub-periods, and changing the frequency of the high frequency power according to an initial frequency set during a period from a start to an end of the ramp-up period in each of one or more consecutive repetitive periods including at least a first repetitive period of the plurality of repetitive periods.

17. The frequency control method according to claim 16.