Patents by Inventor Tatsuro Ohshita

Tatsuro Ohshita 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).

  • 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
  • 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: 11315770
    Abstract: An exhaust device including an exhaust mechanism and an exhaust unit is provided. The exhaust mechanism includes a first blade unit and a second blade unit provided in an exhaust space of a processing vessel including a processing space of a vacuum atmosphere for applying a process to a workpiece. The first blade unit and the second blade unit are arranged coaxially with a periphery of the workpiece, and at least one of the first blade unit and the second blade unit is rotatable. The exhaust unit is provided at a downstream side of the exhaust mechanism and communicates with the exhaust space. The exhaust unit is configured to exhaust gas in the processing vessel.
    Type: Grant
    Filed: November 30, 2018
    Date of Patent: April 26, 2022
    Assignee: Tokyo Electron Limited
    Inventors: Kazuya Nagaseki, Kazuki Moyama, Toshiya Matsuda, Naokazu Furuya, Tatsuro Ohshita
  • 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
  • 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
  • Patent number: 11133157
    Abstract: Provided is a plasma processing apparatus that performs a processing on a processing target substrate by applying plasma of a processing gas on the processing target substrate. The plasma processing apparatus includes: a processing container configured to accommodate the processing target substrate; a lower electrode disposed in the processing container to mount the processing target substrate thereon; an upper electrode disposed in the processing container to face the lower electrode with a processing space being interposed therebetween; a high frequency power source configured to apply a high frequency power between the upper electrode and the lower electrode; a main magnet unit including one or more annular main electromagnetic coils arranged around a central axis; and an auxiliary magnet unit configured to form a magnetic field that perpendicularly or obliquely crosses the central axis in the processing space.
    Type: Grant
    Filed: April 19, 2019
    Date of Patent: September 28, 2021
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Akihiro Yokota, Shinji Himori, Tatsuro Ohshita, Shu Kusano
  • Publication number: 20210296102
    Abstract: An exhaust device including an exhaust mechanism and an exhaust unit is provided. The exhaust mechanism includes a first blade unit and a second blade unit provided in an exhaust space of a processing vessel including a processing space of a vacuum atmosphere for applying a process to a workpiece. The first blade unit and the second blade unit are arranged coaxially with a periphery of the workpiece, and at least one of the first blade unit and the second blade unit is rotatable. The exhaust unit is provided at a downstream side of the exhaust mechanism and communicates with the exhaust space. The exhaust unit is configured to exhaust gas in the processing vessel.
    Type: Application
    Filed: June 9, 2021
    Publication date: September 23, 2021
    Inventors: Kazuya NAGASEKI, Kazuki MOYAMA, Toshiya MATSUDA, Naokazu FURUYA, Tatsuro OHSHITA
  • Publication number: 20200126770
    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: December 20, 2019
    Publication date: April 23, 2020
    Inventors: Koichi Nagami, Kazunobu Fujiwara, Tatsuro Ohshita, Takashi Dokan, Koji Maruyama, Kazuya Nagaseki, Shinji Himori
  • Patent number: 10553407
    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: August 17, 2018
    Date of Patent: February 4, 2020
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Koichi Nagami, Kazunobu Fujiwara, Tatsuro Ohshita, Takashi Dokan, Koji Maruyama, Kazuya Nagaseki, Shinji Himori
  • Publication number: 20190333744
    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: April 24, 2019
    Publication date: October 31, 2019
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Koichi NAGAMI, Tatsuro OHSHITA
  • Publication number: 20190333741
    Abstract: A plasma processing method includes providing a plasma processing apparatus; supplying radio-frequency waves from a radio-frequency power supply; and applying a negative DC voltage to a lower electrode from the at least one DC power supply. In the applying the DC voltage, the DC voltage is cyclically applied to the lower electrode, and in a state where a frequency defining each cycle in which the DC voltage is applied to the lower electrode is set to be lower than 1 MHz, a ratio occupied by a period during which the DC voltage is applied to the lower electrode in the each cycle is regulated.
    Type: Application
    Filed: April 26, 2019
    Publication date: October 31, 2019
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Koichi NAGAMI, Tatsuro OHSHITA, Kazuya NAGASEKI, Shinji HIMORI
  • Publication number: 20190244794
    Abstract: Provided is a plasma processing apparatus that performs a processing on a processing target substrate by applying plasma of a processing gas on the processing target substrate. The plasma processing apparatus includes: a processing container configured to accommodate the processing target substrate; a lower electrode disposed in the processing container to mount the processing target substrate thereon; an upper electrode disposed in the processing container to face the lower electrode with a processing space being interposed therebetween; a high frequency power source configured to apply a high frequency power between the upper electrode and the lower electrode; a main magnet unit including one or more annular main electromagnetic coils arranged around a central axis; and an auxiliary magnet unit configured to form a magnetic field that perpendicularly or obliquely crosses the central axis in the processing space.
    Type: Application
    Filed: April 19, 2019
    Publication date: August 8, 2019
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Akihiro YOKOTA, Shinji HIMORI, Tatsuro OHSHITA, Shu KUSANO
  • Publication number: 20190172689
    Abstract: An exhaust device including an exhaust mechanism and an exhaust unit is provided. The exhaust mechanism includes a first blade unit and a second blade unit provided in an exhaust space of a processing vessel including a processing space of a vacuum atmosphere for applying a process to a workpiece. The first blade unit and the second blade unit are arranged coaxially with a periphery of the workpiece, and at least one of the first blade unit and the second blade unit is rotatable. The exhaust unit is provided at a downstream side of the exhaust mechanism and communicates with the exhaust space. The exhaust unit is configured to exhaust gas in the processing vessel.
    Type: Application
    Filed: November 30, 2018
    Publication date: June 6, 2019
    Inventors: Kazuya NAGASEKI, Kazuki MOYAMA, Toshiya MATSUDA, Naokazu FURUYA, Tatsuro OHSHITA
  • Patent number: 10297428
    Abstract: Provided is a plasma processing apparatus that performs a processing on a processing target substrate by applying plasma of a processing gas on the processing target substrate. The plasma processing apparatus includes: a processing container configured to accommodate the processing target substrate; a lower electrode disposed in the processing container to mount the processing target substrate thereon; an upper electrode disposed in the processing container to face the lower electrode with a processing space being interposed therebetween; a high frequency power source configured to apply a high frequency power between the upper electrode and the lower electrode; a main magnet unit including one or more annular main electromagnetic coils arranged around a central axis; and an auxiliary magnet unit configured to form a magnetic field that perpendicularly or obliquely crosses the central axis in the processing space.
    Type: Grant
    Filed: April 29, 2015
    Date of Patent: May 21, 2019
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Akihiro Yokota, Shinji Himori, Tatsuro Ohshita, Shu Kusano
  • Publication number: 20190122863
    Abstract: Energy of ions irradiated to a chamber main body is reduced. A plasma processing apparatus includes a chamber main body, a placing table and a high frequency power supply unit. The chamber main body is configured to provide a chamber therein. The chamber main body is connected to a ground potential. The placing table has a lower electrode and is provided within the chamber. The high frequency power supply unit is electrically connected to the lower electrode. The high frequency power supply unit is configured to generate an output wave for bias to be supplied to the lower electrode. The high frequency power supply unit is configured to generate the output wave in which a positive voltage component of a voltage waveform of a high frequency power having a fundamental frequency is reduced.
    Type: Application
    Filed: April 14, 2017
    Publication date: April 25, 2019
    Inventors: Kazuya Nagaseki, Tatsuro Ohshita, Koichi Nagami
  • Publication number: 20190057845
    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: August 17, 2018
    Publication date: February 21, 2019
    Inventors: Koichi Nagami, Kazunobu Fujiwara, Tatsuro Ohshita, Takashi Dokan, Koji Maruyama, Kazuya Nagaseki, Shinji Himori
  • Patent number: 9978566
    Abstract: Disclosed is a plasma etching method which is performed using a plasma processing apparatus that is a capacitively coupled plasma processing apparatus, and includes: a processing container; a gas supply unit that supply an etching processing gas into the processing container; a placing table including a lower electrode; an upper electrode provided above the placing table; and a plurality of electromagnets including a plurality of coils, or a plurality of electromagnets each including a coil, on the upper electrode. The plasma etching method includes generating plasma of the processing gas to perform a plasma etching on a single film of a workpiece placed on the placing table; and controlling a current supplied to the plurality of electromagnet to change a distribution of an etching rate of the single film in the diametric direction with respect to the central axis during the generating of the plasma of the processing gas.
    Type: Grant
    Filed: October 7, 2016
    Date of Patent: May 22, 2018
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Akihiro Yokota, Shinji Himori, Tatsuro Ohshita, Shu Kusano, Etsuji Ito, Kazuya Nagaseki
  • Publication number: 20170103877
    Abstract: Disclosed is a plasma etching method which is performed using a plasma processing apparatus that is a capacitively coupled plasma processing apparatus, and includes: a processing container; a gas supply unit that supply an etching processing gas into the processing container; a placing table including a lower electrode; an upper electrode provided above the placing table; and a plurality of electromagnets including a plurality of coils, or a plurality of electromagnets each including a coil, on the upper electrode. The plasma etching method includes generating plasma of the processing gas to perform a plasma etching on a single film of a workpiece placed on the placing table; and controlling a current supplied to the plurality of electromagnet to change a distribution of an etching rate of the single film in the diametric direction with respect to the central axis during the generating of the plasma of the processing gas.
    Type: Application
    Filed: October 7, 2016
    Publication date: April 13, 2017
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Akihiro YOKOTA, Shinji HIMORI, Tatsuro OHSHITA, Shu KUSANO, Etsuji ITO, Kazuya NAGASEKI
  • Patent number: 9343295
    Abstract: A vaporizing unit, in supplying a gas material produced by vaporizing a liquid material onto a substrate to conduct a film forming process, can vaporize the liquid material with high efficiency to suppress generation of particles. With the vaporizing unit, positively or negatively charged bubbles, which have a diameter of 1000 nm or less, are produced in the liquid material, and the liquid material is atomized to form a mist of the liquid material. Further, the mist of the liquid material is heated and vaporized. The fine bubbles are uniformly dispersed in advance in the liquid material, so that very fine and uniform mist particles of the liquid material are produced when the liquid material is atomized, which makes heat exchange readily conducted. By vaporizing the mist of the liquid material, vaporization efficiency is enhanced, and generation of particles can be suppressed.
    Type: Grant
    Filed: May 19, 2014
    Date of Patent: May 17, 2016
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Ikuo Sawada, Sumie Nagaseki, Kyoko Ikeda, Tatsuro Ohshita