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

Abstract

To provide a technique for reducing the degree of reflection of source high frequency power when the source high frequency power is supplied alone.SOLUTION: A disclosed plasma processing apparatus includes a chamber, a substrate support, a radio frequency power supply, and a controller. The substrate support is provided 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 has been 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.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[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 radio frequency power. The plasma processing apparatus uses a bias radio frequency power to attract ions from the plasma generated in the chamber to the substrate. The following Patent Document 1 discloses a plasma processing apparatus that modulates the power level and frequency of the bias radio frequency power. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-246091 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique for reducing the degree of reflection of source high frequency power in a state in which source high frequency power is supplied alone. [Means for solving the problem]

[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 source, and a controller. The substrate support is disposed within the chamber. The radio frequency power source 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. Effect of the Invention

[0006] According to one exemplary embodiment, it is possible to reduce the degree of reflection of source high frequency power in a state in which 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: [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram of a computer-based system that functions as a controller to control the processing performed in an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a diagram for explaining a configuration example of a plasma processing system. [Diagram 3] FIG. 1 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. [Figure 4] 4 is an example timing chart relating to a plasma processing apparatus according to an exemplary embodiment. [Diagram 5] 4 is a flow diagram of a frequency control method according to an exemplary embodiment. [Figure 6] 11 is an example timing chart related to a plasma processing apparatus according to another exemplary embodiment. [Figure 7]13 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment. [Figure 8] 13 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment. [Figure 9] 13 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment. [Figure 10] 13 is an example timing chart related to a plasma processing apparatus according to yet another exemplary embodiment. [Figure 11] 4 is a flow diagram of a frequency control method according to another exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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 source, and a controller. The substrate support is disposed within the chamber. The radio frequency power source 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 radio frequency power source, under the control of a controller, provides pulsed power to generate the plasma.

[0013] In this specification, elements or steps described in the singular "a," "an," or "the" do not exclude a plurality of elements or steps, unless expressly expressly excluded. Moreover, references to "one embodiment" of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that 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. The technical effect may include at least processing a substrate in a plasma processing apparatus using a controller to control pulsed high frequency (HF) RF in generating a plasma.

[0015] Various exemplary embodiments will now be described in detail with reference to the drawings, in which the same or corresponding 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 a system, method, and / or computer program product. The computer program product may include a computer-readable storage medium having computer-readable program instructions stored 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. A non-exhaustive list of more specific examples of computer-readable storage media includes each of (and suitable 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. A computer-readable storage medium, as used in this disclosure, should not be interpreted as a transitory signal in 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., a light pulse through a fiber optic cable), or an electric signal transmitted through an electric wire.

[0019] The computer readable program instructions described in this disclosure can be downloaded from a computer readable storage medium to a suitable computer or processing device, or to an external computer or external storage device via a global network (Internet), a local area network, a wide area network, and / or a wireless network. The network may include copper transmission lines, optical fiber, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface of each computer 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 computer 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, a remote computer or computer server, or 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, wide area network, or global network (Internet). In some embodiments, to carry out aspects of the present disclosure, an electronic circuit, including a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may execute the computer readable program instructions to configure or customize the electronic circuit using information from the computer readable program instructions.

[0021] Aspects of the present disclosure are described with reference to flow diagrams 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 flow diagrams 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 via the processor of the computer or other programmable device to produce a system that performs the functions illustrated 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 manner, such that the computer-readable storage medium storing the instructions is an article of manufacture that includes instructions that implement aspects of the functionality illustrated in the flow diagrams and block diagrams of this disclosure.

[0023] 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 resulting in a computer-implemented process, such that the instructions executing on the computer, other programmable apparatus, or other device may perform the functions illustrated 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, a 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 illustrated 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. Details of remote computer 815, web server 820, cloud storage server 825, and computer server 830 are not shown, although 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), a desktop computer, a notebook computer, a tablet computer, a netbook computer, a personal digital assistant (PDA), a 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 a combination of chips and related devices) in some embodiments, while in other embodiments a combination of functions may be implemented on a single chip (sometimes referred to as 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 Holdings, 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 interconnect bus or serial interconnect bus such as ISA, PCI, PCI Express (PCI-e), AGP, etc.

[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] Programs 848 may be collections of machine-readable instructions and / or data that are 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, programs 848 may be transferred from non-volatile storage 845 to memory 840 prior to 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 peripheral interface 855 may allow data input and output to and from other devices locally connected to the computer 805. The peripheral interface 855 may provide a connection to, for example, 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 used to perform embodiments of the present disclosure, such as the program 848, may be stored on a portable computer readable storage medium. In such an embodiment, the software may be loaded into the non-volatile storage 845 or may be loaded directly into the memory 840 via the peripheral interface 855. The peripheral 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, the network interface 850 provides for communication with other computer systems / devices and storage systems / devices external to the computer 805. The software programs and data described herein may be downloaded to the non-volatile storage 845 via the network interface 850 and the network 810 from the remote computer 815, the web server 820, the cloud storage server 825, the computer server 830, etc. Additionally, the systems and methods described in the present disclosure may be performed by one or more computers connected to the computer 805 via the network interface 850 and the network 810. For example, in some embodiments, the systems and methods of the present disclosure may be performed by the remote computer 815, the computer server 830, or a combination of interconnected computers on the network 810.

[0037] Data, data sets, 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] A circuit, as used herein, may be defined as one or more of an electronic component (such as a semiconductor device), multiple components connected directly to each other or interconnected by 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, the circuit represented by a network system may include a serverless computer system corresponding to a virtual set of multiple hardware resources. The 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, and other programmable devices capable of communicating with other devices over a network. The circuit may be a general purpose computer, a special purpose computer, or 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 is considered a processing circuit or circuitry because it has transistors and other circuitry. The circuitry 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 perform the systems and methods of the present disclosure, such that the instructions are included in the circuitry or are executed by one or more processors of a programmable device that includes the circuitry to 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 for explaining a configuration example of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing device 1 and a control unit 2. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support unit 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space, and at least one gas 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 unit 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 formed in the plasma processing space may be a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR plasma), a helicon wave plasma (HWP), a surface wave plasma (SWP), or the like. Also, various types of plasma generating units may be used, including an alternating current (AC) plasma generating unit and a direct current (DC) plasma generating unit.

[0041] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various steps described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform various steps described herein. In one embodiment, a part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 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 a program stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[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 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 processing gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed in 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 part of a 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 a 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 the one or more annular members is an edge ring. Although not shown, the substrate support 11 may include a temperature adjustment 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 adjustment module may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a.

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

[0046] The gas supply 20 may include one or more gas sources 21 and at least one or more flow controllers 22. In one embodiment, the gas supply 20 is configured to supply one or more process gases from respective gas sources 21 through respective flow controllers 22 to the showerhead 13. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply 20 may include one or more flow modulation devices to 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 adjusted 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 For example, the source frequency f is 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 a source high frequency power HF and outputs 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 device 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 an electrode common to a bias electrode described later. Alternatively, the high frequency electrode may be an upper electrode. The matching device 31m includes a matching circuit. The matching circuit of the matching device 31m has a variable impedance. The matching circuit of the matching device 31m is controlled by the control unit 30c. The impedance of the matching circuit of the matching device 31m is adjusted so as to match the impedance of 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 a sensor separated from the matching box 31m, or may be a part of the matching box 31m.

[0053] The one or more sensors 31s may include a directional coupler configured to detect a power level of a reflected wave of the source high frequency power HF returned from a load of the high frequency power supply 31 and to 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 HF and current I HF Detects the voltage V HF and current I HF from the load impedance Z 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 inputs 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 provide an electric bias EB (or bias energy) to the bias electrode. The bias power supply 32 may be configured to provide a pulse of the electric bias EB to the bias electrode. In this case, the bias power supply 32 may specify the timing of each of the multiple pulses by a signal provided from the 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 of 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 electric bias EB may be a bias high 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 of 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 high 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 device 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 composed of 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 a part of the matching device 31m, may be a part of the high frequency power supply 31, or may be a control unit separated 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 isolated supply period s The control unit 30c sets the period P HO The source frequency f at each time s is the source frequency f when the source high frequency power HF is supplied alone. S and the degree of reflection of the source high frequency power HF is set so as to suppress the degree of reflection of the source high frequency power HF. HO is a period during which no electrical bias EB is supplied and the source radio frequency power HF is supplied alone.

[0063] In various embodiments, the degree of reflection may be obtained as a power level of a reflected wave of the source high frequency power HF. The degree of reflection may be obtained as a value of a ratio of a power level of a reflected wave of the source high frequency power HF to a power level of a forward wave of the source high frequency power HF or a set output power level of the source high frequency power HF. Alternatively, the degree of reflection may be obtained as a ratio of an 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 The reflectance may be obtained by one or more sensors 31s or may be determined from measurements obtained by one or more sensors 31s.

[0064] Below, period P HO Source frequency f at S Various embodiments relating to 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. 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 a source frequency f 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 for generating plasma, but an electric bias EB is not used. In the first embodiment, the plasma processing apparatus 1 does not need to include the bias power supply 32 and the matching box 32m. In addition, the plasma processing apparatus 1 does not need to include the pulse controller 34.

[0068] In the first embodiment, the high-frequency power supply 31 operates in a period P HO The source high frequency power HF is supplied 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 high frequency power HF provides a continuous wave.

[0069] In the first embodiment, the period P HO is a set of a number of subperiods SP, i.e., I subperiods SP1, SP2, . . . , SP I A number of sub-periods SP1, SP2,...,SP I is the period P HO Period P Bis divided into I sub-periods. The time lengths of the multiple sub-periods SP may be the same as each other or may be different from each other. The time length of each of the multiple 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 subperiods SP S The start-up period P S The high frequency power supply 31 may include a period of plasma ignition. 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 S Specifically, the control unit 30c performs the start-up process FSA during the start-up period P S between the start and end of the source frequency f S is changed according to the initial frequency set. The initial frequency set is prepared in advance and stored in a storage unit accessible to the control unit 30c. The initial frequency set may be experimentally obtained or may be determined based on past processing results.

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

[0073] In one embodiment, the sub-period SP iOne or more subperiods preceding the subperiod SP iーv (First Subperiod) and Subperiod SP i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. If the duration of each of the multiple sub-periods SP is short, u may be equal to or greater than 20 in order to reduce the calculation load. For example, if the duration of each of the multiple sub-periods SP is 50 nsec, then sub-periods SP i is the sub-period SP iーu This is the period 1 μs after

[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 the subperiod SP iーv The degree of reflection of the source high frequency power HF in the subperiod SP iーu Depending on the change in the degree of reflection of the source high frequency power HF in the subperiod SP i In order 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 subperiod SP iーv The degree of reflection of the source high frequency power HF in the subperiod 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 [iv] to source frequency f S [iu] and the source frequency f S The frequency given to [iu] is the source frequency f S Set as [i]. Subperiod SP iーv The degree of reflection of the source high frequency power HF in the subperiod SP iーu If the change in the degree of reflection of the source high frequency power HF at the source frequency fS [iv] to source frequency f S The change in the direction opposite to the change in [iu] is the source frequency f S The frequency given to [iu] 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. Also, according to the first embodiment, the rise time until the plasma becomes stable can be accelerated. Also, according to the first embodiment, abnormal discharge of the plasma can be suppressed. Also, according to the first embodiment, the source frequency f S Since reflection is suppressed by adjusting the impedance, the operation of the variable capacitor of the matching device 31m is reduced, and the life of the variable capacitor can be improved.

[0077] Reference is now made to Fig. 5. Fig. 5 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") may be performed in a chamber 10 with a substrate W placed on a substrate support 11. In method MTA, plasma processing may be performed on the substrate W. The plasma processing in method MTA may include plasma etching of the substrate W.

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

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

[0080] In step STAc, the sequential feedback process FSB described above in relation to the first embodiment is performed. That is, in step STAc, the source frequency f S However, when the source high frequency power HF is supplied alone, the source frequency f S and 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 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" for 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" for the source high frequency power HF indicates that the supply of the source high frequency power HF is stopped. In FIG. 6, "ON" for the electric bias EB indicates that the electric bias EB is being supplied, and "OFF" for the electric bias EB indicates that the supply of the electric bias EB is stopped. In FIG. 6, the frequency setting method is a source frequency f S In the second embodiment, the frequency setting method includes a start-up process FSA, a successive feedback process FSB, and an inter-pulse feedback process FSC.

[0083] In the second embodiment, the high frequency power supply 31 is configured to supply a source high frequency power HF in one of two periods in each of a plurality of pulse periods PC (i.e., pulse periods PC1, PC2, . . . ). 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 Including period P HOis one of two periods in each of the multiple pulse periods PC, and the period P BO is the other period.

[0084] In the second embodiment, the high frequency power supply 31 is configured to generate a pulse having a period P HO The 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 multiple 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 radio frequency power HF at the time 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 radio frequency power HF at the time period P BO The power level of the source radio frequency power HF in may be higher than that of the source radio frequency power HF in the

[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 source RF power without supplying electrical bias EB HF This is the sole supply period during which the product is supplied 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 P Bis the start-up period P S It may be a period following.

[0087] As shown in FIG. 6, the control unit 30c controls the rising period P in each of one or more consecutive pulse periods including at least the first pulse period PC1 among the plurality of pulse periods PC. S Specifically, the control unit 30c performs the start-up process FSA during the start-up period P S between the start and end of the source frequency f 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 experimentally obtained or may be determined based on past processing results. The number of one or more consecutive pulse periods including the first pulse period PC1 may be 2 or more and 20 or less.

[0088] The rising period P of each pulse period PC after one or more successive pulse periods including the first pulse period PC1 S In this case, the control unit 30c performs pulse-to-pulse feedback processing FSC. Specifically, the control unit 30c performs pulse period PC n During the launch period P S The source frequency f at each phase in S , the pulse period PC n-q In-phase source frequency f S Pulse period PC n-p In-phase source frequency f S and the pulse period PC n-q The degree of reflection of the source high frequency power HF in phase with the pulse period PC n-p Depending on the change in the degree of reflection of the source high frequency power HF in phase with the pulse period PC n The pulse period PC is set so as 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 nTherefore, the same phase in multiple 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-p are the n-th pulse period, the (nq)-th pulse period, and the (np)-th pulse period among the multiple 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 P n During the launch period P S The phase in m The phase α m is the start-up period P S In one example, the phase of the pulse period PC nーq During the start-up period S Phase α in m The degree of reflection of the source high frequency power HF at the pulse period PC nーp During the launch period P S Phase α in 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 [nq,α m ] to the source frequency f S [np,α m ] to the source frequency f S [np,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 During the start-up period S Phase α in m Source frequency f at S The pulse period PC nーq During the start-up period S Phase α in mThe degree of reflection of the source high frequency power HF at the pulse period PC nーp During the start-up period S Phase α in 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 [nq,α m ] to the source frequency f S [np,α m ] to the source frequency f S [np,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 may start after a predetermined time has elapsed. B is the start-up period P S 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 rising period P S and the rising 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 a period P HO Alternatively, as shown in FIG. 7, the control unit 30c may perform the start-up process FSA, then the pulse-to-pulse feedback process FSC, and then the sequential feedback process FSB. HOIn this case, only the pulse-to-pulse feedback process FSC may be performed. In this case, the period P HO The source frequency f from the start to the end of S may be changed according to a different set of initial frequencies.

[0093] In the second embodiment, the period P HO is divided into a number of sub-periods, and each of these sub-periods is called a period P HO The above-mentioned 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 radio frequency power HF in the period P HO In this case, the level may be changed to multiple levels within 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] Hereinafter, another modified example of the second embodiment will be described with reference to Fig. 8. As shown in Fig. 8, in the other modified example of the second embodiment, a period P HO The power level of the source radio frequency power HF in the period P HO For example, the period P HOmay include one or more periods in which the power level of the source high frequency power HF has a level indicated by "LOW" and one or more periods in which the power level has a level indicated by "OFF". The level indicated by "LOW" is lower than the level indicated by "HIGH". The level indicated by "OFF" is zero. In other words, during the period having the level indicated by "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 that includes the beginning of the period P S In two periods including the start and end points, source high frequency power having a level indicated by "LOW" is supplied, and in the period between these two periods, the supply of 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 the above, only the pulse-to-pulse feedback process FSC may be performed. HO In the period including the start point of the period P, the start-up process FSA is performed. HO In other periods within the pulse period PC, only the pulse-to-pulse feedback process FSC may be performed. In this case, in each of at least the first and second pulse periods PC, HO The source frequency f from the start to the end of S may be changed according to a different set of initial frequencies.

[0097] According to the second embodiment, during 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 accelerated. 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 HOIn 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 reflection is suppressed by adjusting the impedance, the operation of the variable capacitor of the matching device 31m is reduced, and the life of the variable capacitor can be improved.

[0098] [Third embodiment]

[0099] Referring to Figure 9, the source frequency f S A third embodiment relating to the setting (or change) of the source high frequency power HF, the electrical bias EB, the frequency setting method, the source frequency f in the third embodiment will be described. FIG. 9 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 S , and a timing chart of the degree of reflection RD. 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 a source frequency f S In the third embodiment, the frequency setting method includes a start-up 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 difference between the second embodiment and the third embodiment.

[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 BOThat is, in the third embodiment, the high frequency power supply 31 stops the supply of the source high frequency power HF during the period in which the electric bias EB is being supplied.

[0101] Period P in the third embodiment HO Source frequency f within S The process of setting is the same as that of the second embodiment. HO Source frequency f at S The process is similar to that of setting

[0102] In the third embodiment, the rising period P S and the rising 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 a period P HO Alternatively, as shown in FIG. 10, the control unit 30c may perform the start-up process FSA, then the pulse-to-pulse feedback process FSC, and then the sequential feedback process FSB. HO In this case, only the pulse-to-pulse feedback process FSC may be performed. In this case, the period P HO The source frequency f from the start to the end of S may be changed according to a different set of initial frequencies.

[0104] In the third embodiment, the period P HO is divided into a number of sub-periods, and each of these sub-periods is called a period P HOThe above-mentioned 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 radio frequency power HF in the period P HO In this case, the level may be changed to multiple levels within 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, a frequency control method 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 a period P HO 11 shows a flow of a frequency control method in the embodiment. 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 a 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 on the substrate W.

[0107] The method MTB starts with step STBa, which includes a period P HO In 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 successive pulse periods including a first pulse period of the plurality of pulse periods PC. S In step STBb, the above-mentioned 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 detecting 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 a process for determining whether the period P HO In the start-up period P S Alternatively, the successive feedback process FSB may be performed after a period P HO In the above, the feedback process FSC may be performed after the pulse-to-pulse feedback process FSC which 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. In addition, elements in different embodiments can 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 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 chamber; a substrate support disposed within the chamber; a radio frequency power source configured to provide a source radio frequency power to generate a plasma from a gas in the chamber; A control unit; Equipped with the control unit is configured to set a source frequency of the source high frequency power when the source high frequency power is supplied alone, in accordance with the source frequency when the source high frequency power was previously supplied alone and a degree of reflection of the source high frequency power, so as to suppress a degree of reflection of the source high frequency power. Plasma processing equipment.

[0115] [E2] the high frequency power supply is configured to continuously supply the source high frequency power within a single supply period; The single supply period includes a plurality of sub-periods; the control unit is configured to set the source frequency in an i-th sub-period among the plurality of sub-periods in accordance with 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 among the plurality of sub-periods, so as to suppress a degree of reflection of the source high frequency power. The plasma processing apparatus according to E1.

[0116] [E3] the one or more subperiods include a first subperiod and a second subperiod following the first subperiod; The control unit is setting the source frequency in the second subperiod to a frequency different from the source frequency in the first subperiod; setting the source frequency in the i-th subperiod so as to suppress a degree of reflection of the source high frequency power in response to a change from the source frequency in the first subperiod to the source frequency in the second subperiod and a change from a degree of reflection of the source high frequency power in the first subperiod to a degree of reflection of the source high frequency power in the second subperiod; The plasma processing apparatus according to E2,

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

[0118] [E5] 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 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 E2 to E4.

[0119] [E6] 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 radio frequency power source is configured to supply the source radio frequency power during one of two periods in each of a plurality of pulse periods; the bias power supply is configured to stop supplying the electric bias to the substrate support during one of the two periods in each of the plurality of pulse periods and to supply the electric bias to the substrate support during the other of the two periods; 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 multiple pulse periods, in accordance with a change from the source frequency at the same phase in an (nq)-th pulse period among the multiple pulse periods to the source frequency at the same phase in an (np)-th pulse period among the multiple pulse periods, and a change from a degree of reflection of the source high frequency power at the same phase in the (nq)-th pulse period to a degree of reflection of the source high frequency power at the same phase in the (np)-th pulse period, wherein q and p are integers equal to or greater than 1 such that q>p. The plasma processing apparatus according to E1.

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

[0121] [E8] Each of the plurality of pulse periods includes a plurality of sub-periods following the ramp-up period; the control unit is configured to set the source frequency in an i-th sub-period among the plurality of sub-periods of each of the plurality of pulse periods, in accordance with 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 among the plurality of sub-periods, so as to suppress a degree of reflection of the source high frequency power. The plasma processing apparatus according to E6 or 7.

[0122] [E9] the one or more subperiods include a first subperiod and a second subperiod following the first subperiod; The control unit is setting the source frequency in the second subperiod to a frequency different from the source frequency in the first subperiod; setting the source frequency in the i-th subperiod so as to suppress a degree of reflection of the source high frequency power in response to a change from the source frequency in the first subperiod to the source frequency in the second subperiod and a change from a degree of reflection of the source high frequency power in the first subperiod to a degree of reflection of the source high frequency power in the second subperiod; The plasma processing apparatus according to E8,

[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 in the other period.

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

[0126] [E13] a radio frequency power source configured to provide a source radio frequency power to generate a plasma from a gas in a chamber of the plasma processing device; A control unit; Equipped with the control unit is configured to set a source frequency of the source high frequency power when the source high frequency power is supplied alone, in accordance with the source frequency when the source high frequency power was previously supplied alone and a degree of reflection of the source high frequency power, so as to suppress a degree of reflection of the source high frequency power. Power supply system.

[0127] [E14] (a) providing a source radio frequency power from a radio frequency power source to generate a plasma from a gas in a chamber of a plasma processing device; (b) in (a), setting a source frequency of the source high frequency power when the source high frequency power is supplied alone, 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, so as to suppress the degree of reflection of the source high frequency power; A frequency control method comprising:

[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. [Explanation of symbols]

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

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 prior to 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 in 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 in the individual supply period in the (n-q)-th repetition period among the multiple repetition periods to the frequency of the high frequency power at the same phase in the ramp-up period in the individual supply period in the (n-p)-th repetition period among the multiple repetition periods, and a change from a degree of reflection of the high frequency power at the same phase in the ramp-up period in 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 in the individual supply period in the (n-p)-th repetition period, where q and p are integers equal to or greater than 1 such that q>p. The plasma processing apparatus according to claim 3 .

5. 4. 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 repetitive periods including at least a first repetitive period among the plurality of repetitive periods.

6. the single supply period further includes a ramp-up period prior to 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 prior to 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. 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 repetitive periods including at least a first repetitive period of the plurality of repetitive periods.

15. the single supply period further includes a ramp-up period prior to 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. 18. The frequency control method of 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 repetitive periods including at least a first repetitive period of the plurality of repetitive 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.

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