Patents by Inventor Koichi Nagami

Koichi Nagami has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11887817
    Abstract: The disclosed plasma processing apparatus is provided with a chamber, a substrate support, and a power source system. The substrate support has an electrode and configured to support a substrate in the chamber. The power source system is electrically connected to the electrode and configured to apply a bias voltage to the electrode to draw ions from a plasma in the chamber into the substrate on the substrate support. The power source system is configured to output a first pulse to the electrode in a first period and output a second pulse to the electrode in a second period after the first period, as the bias voltage. Each of the first pulse and the second pulse is a pulse of a voltage. A voltage level of the first pulse is different from a voltage level of the second pulse.
    Type: Grant
    Filed: April 16, 2021
    Date of Patent: January 30, 2024
    Assignee: Tokyo Electron Limited
    Inventor: Koichi Nagami
  • Publication number: 20240006154
    Abstract: A plasma processing method according to an exemplary embodiment includes applying a first direct-current voltage to a lower electrode of a substrate support provided in a chamber of a plasma processing apparatus, in a first period during generation of plasma in the chamber. The plasma processing method further includes applying a second direct-current voltage to the lower electrode in a second period different from the first period during generation of plasma in the chamber. The second direct-current voltage has a level different from a level of the first direct-current voltage. The second direct-current voltage has a same polarity as a polarity of the first direct-current voltage.
    Type: Application
    Filed: August 10, 2023
    Publication date: January 4, 2024
    Applicant: Tokyo Electron Limited
    Inventors: Chishio KOSHIMIZU, Shin HIROTSU, Takenobu IKEDA, Koichi NAGAMI, Shinji HIMORI
  • Publication number: 20230411128
    Abstract: A plasma processing apparatus includes: a placement table serving as a lower electrode and configured to place thereon a workpiece to be subjected to a plasma processing; a DC power supply configured to alternately generate a positive DC voltage and a negative DC voltage to be applied to the placement table; and a controller configured to control an overall operation of the plasma processing apparatus. The controller is configured to: measure a voltage of the workpiece placed on the placement table; calculate, based on the measured voltage of the workpiece, a potential difference between the placement table and the workpiece in a period during which the negative DC voltage is applied to the placement table; and control the DC power supply such that a value of the negative DC voltage applied to the placement table is shifted by a shift amount that decreases the calculated potential difference.
    Type: Application
    Filed: August 3, 2023
    Publication date: December 21, 2023
    Applicant: Tokyo Electron Limited
    Inventors: Koichi NAGAMI, Tatsuro OHSHITA
  • Patent number: 11776795
    Abstract: A plasma processing apparatus includes: a placement table serving as a lower electrode and configured to place thereon a workpiece to be subjected to a plasma processing; a DC power supply configured to alternately generate a positive DC voltage and a negative DC voltage to be applied to the placement table; and a controller configured to control an overall operation of the plasma processing apparatus. The controller is configured to: measure a voltage of the workpiece placed on the placement table; calculate, based on the measured voltage of the workpiece, a potential difference between the placement table and the workpiece in a period during which the negative DC voltage is applied to the placement table; and control the DC power supply such that a value of the negative DC voltage applied to the placement table is shifted by a shift amount that decreases the calculated potential difference.
    Type: Grant
    Filed: April 24, 2019
    Date of Patent: October 3, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Koichi Nagami, Tatsuro Ohshita
  • Patent number: 11764034
    Abstract: A plasma processing method according to an exemplary embodiment includes applying a first direct-current voltage to a lower electrode of a substrate support provided in a chamber of a plasma processing apparatus, in a first period during generation of plasma in the chamber. The plasma processing method further includes applying a second direct-current voltage to the lower electrode in a second period different from the first period during generation of plasma in the chamber. The second direct-current voltage has a level different from a level of the first direct-current voltage. The second direct-current voltage has a same polarity as a polarity of the first direct-current voltage.
    Type: Grant
    Filed: May 19, 2020
    Date of Patent: September 19, 2023
    Assignee: Tokyo Electron Limited
    Inventors: Chishio Koshimizu, Shin Hirotsu, Takenobu Ikeda, Koichi Nagami, Shinji Himori
  • Patent number: 11764082
    Abstract: A control method of a plasma processing apparatus including a first electrode and a second electrode includes supplying a bias power to the first electrode, and supplying a negative DC voltage to the second electrode. The negative DC voltage periodically repeats a first state that takes a first voltage value and a second state that takes a second voltage value having an absolute value smaller than the first voltage value. The control method further includes a first control process of applying the first state of the negative DC voltage in a partial time period within each cycle of a signal synchronized with a cycle of a radio frequency of the bias power, or in a partial time period within each cycle of a periodically varying parameter measured in a transmission path of the bias power, and applying the second state continuously with the first state.
    Type: Grant
    Filed: July 17, 2019
    Date of Patent: September 19, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Chishio Koshimizu, Shinji Kubota, Koji Maruyama, Takashi Dokan, Koichi Nagami
  • Publication number: 20230260766
    Abstract: A plasma processing apparatus includes: a chamber; a substrate support disposed in the chamber, the substrate support including a lower electrode; an edge ring disposed to surround a substrate on the substrate support; an upper electrode disposed above the substrate support; a first RF power supply; a first DC power supply; and a controller configured to cause: (a) starting supply of a first RF power from the first RF power supply to the upper electrode or the lower electrode; and (b) after (a), starting the application of a first DC voltage from the first DC power supply to the edge ring when a first delay time elapses.
    Type: Application
    Filed: April 19, 2023
    Publication date: August 17, 2023
    Applicant: Tokyo Electron Limited
    Inventors: Natsumi TORII, Koichi NAGAMI
  • Patent number: 11646181
    Abstract: A plasma processing apparatus includes: a chamber; a substrate support provided inside the chamber and including an electrode, an electrostatic chuck provided on the electrode, and an edge ring that is disposed on the electrostatic chuck while surrounding the substrate placed on the electrostatic chuck; a radio-frequency power supply that supplies radio-frequency power for generating plasma from a gas within the chamber; a DC power supply that applies a negative DC voltage to the edge ring; and a controller that controls the radio-frequency power and the DC voltage. The controller controls the apparatus to execute a process including: (a) stopping application of the DC voltage while stopping supply of the radio-frequency power; and (b) starting the application of the DC voltage after a predetermined delay time elapses since the supply of the radio-frequency power.
    Type: Grant
    Filed: July 15, 2021
    Date of Patent: May 9, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Natsumi Torii, Koichi Nagami
  • Publication number: 20230078135
    Abstract: There is provided a plasma processing apparatus for performing plasma processing or a substrate, comprising: a chamber; a substrate support disposed in the chamber and including a base, an electrostatic chuck on the base, and an edge ring disposed to surround a substrate mounted on the electrostatic chuck; a Radio Frequency (RF) power supply for supplying RF power for generating plasma from gases in the chamber; a DC power supply for applying a negative DC voltage to the edge ring; a waveform control element for controlling a waveform of the DC voltage; and a controller for controlling a time taken for the DC voltage to reach a desired value by adjusting a constant of the waveform control element.
    Type: Application
    Filed: September 15, 2022
    Publication date: March 16, 2023
    Applicant: Tokyo Electron Limited
    Inventors: Natsumi TORII, Koichi NAGAMI, Chishio KOSHIMIZU, Jun ABE
  • Patent number: 11594398
    Abstract: An apparatus for plasma processing is configured to generate plasma in a chamber and periodically apply a pulsed negative DC voltage to an upper electrode from a DC power supply in the plasma processing on a substrate and in plasma cleaning. A duty ratio of the pulsed negative DC voltage used for the plasma processing is smaller than a duty ratio of the pulsed negative DC voltage used for the plasma cleaning. An absolute value of an average value of an output voltage of the DC power supply used for the plasma processing is smaller than an absolute value of an average value of the output voltage of the DC power supply used for the plasma cleaning.
    Type: Grant
    Filed: February 13, 2020
    Date of Patent: February 28, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Yusuke Aoki, Fumiya Takata, Toshikatsu Tobana, Shinya Morikita, Kazunobu Fujiwara, Jun Abe, Koichi Nagami
  • Publication number: 20230056323
    Abstract: A plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed in the plasma processing chamber, and including a lower electrode, an electrostatic chuck, and an edge ring disposed to surround a substrate mounted on the electrostatic chuck; a driving device; an upper electrode disposed above the substrate support. In an example, the apparatus further comprises a source RF power supply; a bias RF power supply configured to supply bias RF power to the lower electrode; at least one conductor; a DC power supply; an RF filter electrically; and a controller configured to control the driving device and the at least one variable passive element, and adjust an incident angle of an ion in the plasma with respect to an edge area of the substrate mounted on the electrostatic chuck.
    Type: Application
    Filed: August 17, 2022
    Publication date: February 23, 2023
    Applicant: Tokyo Electron Limited
    Inventors: Natsumi TORII, Koichi NAGAMI
  • Publication number: 20220384154
    Abstract: In a disclosed plasma processing apparatus, an electrostatic chuck provided in a chamber includes a first region on which a substrate is placed and a second region on which an edge ring is placed. The first region includes a first electrode provided therein. The second region including a second electrode provided therein. A first feed line connects the first electrode and a bias power supply generating a pulse of a voltage applied to the first electrode to each other. A second feed line connects the second electrode and the bias power supply or another bias power supply generating a pulse of the voltage applied to the second electrode to each other. The second feed line includes one or more sockets and one or more feed pins. The one or more feed pins have flexibility in a radial direction thereof and are fitted into the one or more sockets.
    Type: Application
    Filed: May 25, 2022
    Publication date: December 1, 2022
    Applicant: Tokyo Electron Limited
    Inventors: Yusuke HAYASAKA, Atsushi SASAKI, Kazuya MATSUMOTO, Shingo TAKAHASHI, Koichi NAGAMI
  • Publication number: 20220301825
    Abstract: A disclosed plasma processing method includes generating plasma in a chamber of a plasma processing apparatus by supplying radio frequency power from a radio frequency power source in a first period. The plasma processing method further includes stopping supply of the radio frequency power from the radio frequency power source in a second period following the first period. The plasma processing method further includes applying a negative direct-current voltage from a bias power source to a substrate support in a third period following the second period. In the third period, the radio frequency power is not supplied. In the third period, the negative direct-current voltage is set to generate ions in a chamber by secondary electrons that are emitted by causing ions in the chamber to collide with a substrate.
    Type: Application
    Filed: June 8, 2022
    Publication date: September 22, 2022
    Applicant: Tokyo Electron Limited
    Inventors: Shinji KUBOTA, Kazuya NAGASEKI, Shinji HIMORI, Koichi NAGAMI
  • Publication number: 20220246400
    Abstract: There is provided a radio frequency power filter circuit used in a plasma processing apparatus that includes an electrode and a feeding body connected to a center of a rear surface of the electrode and generates plasma by applying radio frequency power, the filter circuit including a series resonance circuit provided in a wiring line between a conductive member provided in the plasma processing apparatus and a power supply configured to supply DC power or power having a frequency of less than 400 kHz to the conductive member, and including a coil connected in series to the wiring line and a capacitor connected between the wiring line and a ground. A central axis of the coil and a central axis of the feeding body coincide with each other.
    Type: Application
    Filed: January 28, 2022
    Publication date: August 4, 2022
    Inventors: Koji YAMAGISHI, Yuji AOTA, Koichi NAGAMI, Kota ISHIHARADA
  • Patent number: 11387077
    Abstract: A disclosed plasma processing method includes generating plasma in a chamber of a plasma processing apparatus by supplying radio frequency power from a radio frequency power source in a first period. The plasma processing method further includes stopping supply of the radio frequency power from the radio frequency power source in a second period following the first period. The plasma processing method further includes applying a negative direct-current voltage from a bias power source to a substrate support in a third period following the second period. In the third period, the radio frequency power is not supplied. In the third period, the negative direct-current voltage is set to generate ions in a chamber by secondary electrons that are emitted by causing ions in the chamber to collide with a substrate.
    Type: Grant
    Filed: November 24, 2020
    Date of Patent: July 12, 2022
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Shinji Kubota, Kazuya Nagaseki, Shinji Himori, Koichi Nagami
  • Publication number: 20220139672
    Abstract: There is a plasma processing apparatus comprising: a chamber; a substrate support provided in the chamber, the substrate support including a bias electrode; a plasma generator configured to generate plasma from a gas in the chamber; and a bias power supply electrically connected to the bias electrode and configured to generate a sequence of a plurality of voltage pulses applied to the bias electrode, wherein each of the plurality of voltage pulses has a leading edge period in which the voltage pulse transitions from a reference voltage level to a pulse voltage level and a trailing edge period in which the voltage pulse transitions from the pulse voltage level to the reference voltage level, and at least one of a time length of the leading edge period and a time length of the trailing edge period is greater than 0 seconds and less than or equal to 0.5 microseconds.
    Type: Application
    Filed: November 5, 2021
    Publication date: May 5, 2022
    Applicant: Tokyo Electron Limited
    Inventors: Tatsuro OHSHITA, Koichi NAGAMI
  • Patent number: 11251048
    Abstract: A plasma processing method according to an exemplary embodiment includes generating plasma from a film formation gas in a chamber of a plasma processing apparatus by supplying radio frequency power from a radio frequency power source. The plasma processing method further includes forming a protective film on an inner wall surface of a side wall of the chamber by depositing a chemical species from the plasma on the inner wall surface. In the forming a protective film, a pulsed negative direct-current voltage is periodically applied from a direct-current power source device to an upper electrode of the plasma processing apparatus.
    Type: Grant
    Filed: June 9, 2020
    Date of Patent: February 15, 2022
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Yusuke Aoki, Toshikatsu Tobana, Fumiya Takata, Shinya Morikita, Kazunobu Fujiwara, Jun Abe, Koichi Nagami
  • Publication number: 20220028665
    Abstract: A decrease of an etching rate of a substrate can be suppressed, and energy of ions irradiated to an inner wall of a chamber main body can be reduced. A plasma processing apparatus includes a DC power supply configured to generate a negative DC voltage to be applied to a lower electrode of a stage. In a plasma processing performed by using the plasma processing apparatus, a radio frequency power is supplied to generate plasma by exciting a gas within a chamber. Further, the negative DC voltage from the DC power supply is periodically applied to the lower electrode to attract ions in the plasma onto the substrate placed on the stage. A ratio occupied, within each of cycles, by a period during which the DC voltage is applied to the lower electrode is set to be equal to or less than 40%.
    Type: Application
    Filed: October 7, 2021
    Publication date: January 27, 2022
    Inventors: Koichi Nagami, Kazunobu Fujiwara, Tatsuro Ohshita, Takashi Dokan, Koji Maruyama, Kazuya Nagaseki, Shinji Himori
  • Publication number: 20220020576
    Abstract: A plasma processing apparatus includes: a chamber; a substrate support provided inside the chamber and including an electrode, an electrostatic chuck provided on the electrode, and an edge ring that is disposed on the electrostatic chuck while surrounding the substrate placed on the electrostatic chuck; a radio-frequency power supply that supplies radio-frequency power for generating plasma from a gas within the chamber; a DC power supply that applies a negative DC voltage to the edge ring; and a controller that controls the radio-frequency power and the DC voltage. The controller controls the apparatus to execute a process including: (a) stopping application of the DC voltage while stopping supply of the radio-frequency power; and (b) starting the application of the DC voltage after a predetermined delay time elapses since the supply of the radio-frequency power.
    Type: Application
    Filed: July 15, 2021
    Publication date: January 20, 2022
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Natsumi TORII, Koichi NAGAMI
  • Patent number: 11170979
    Abstract: A decrease of an etching rate of a substrate can be suppressed, and energy of ions irradiated to an inner wall of a chamber main body can be reduced. A plasma processing apparatus includes a DC power supply configured to generate a negative DC voltage to be applied to a lower electrode of a stage. In a plasma processing performed by using the plasma processing apparatus, a radio frequency power is supplied to generate plasma by exciting a gas within a chamber. Further, the negative DC voltage from the DC power supply is periodically applied to the lower electrode to attract ions in the plasma onto the substrate placed on the stage. A ratio occupied, within each of cycles, by a period during which the DC voltage is applied to the lower electrode is set to be equal to or less than 40%.
    Type: Grant
    Filed: December 20, 2019
    Date of Patent: November 9, 2021
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Koichi Nagami, Kazunobu Fujiwara, Tatsuro Ohshita, Takashi Dokan, Koji Maruyama, Kazuya Nagaseki, Shinji Himori