Patents by Inventor Takeshi Asayama

Takeshi Asayama 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: 20230318252
    Abstract: A laser system includes an oscillation stage laser configured to output first laser light, and an amplification stage laser configured to amplify the first laser light and output second laser light. A control method of the laser system includes determining a condition under which an amplification characteristic of the amplification stage laser changes, acquiring relationship between pulse energy of the first laser light and a parameter of the second laser light when the condition is determined to be satisfied, and setting target pulse energy of the first laser light based on the relationship.
    Type: Application
    Filed: June 9, 2023
    Publication date: October 5, 2023
    Applicant: Gigaphoton Inc.
    Inventor: Takeshi ASAYAMA
  • Patent number: 11451003
    Abstract: A laser gas regenerating apparatus regenerates a discharged gas discharged from at least one ArF excimer laser apparatus and supplies the regenerated gas to the at least one ArF excimer laser apparatus connected to a first laser gas supply source that supplies a first laser gas and to a second laser gas supply source that supplies a second laser gas. The laser gas regenerating apparatus includes a data obtaining unit that obtains data on a supply amount of the second laser gas supplied to the at least one ArF excimer laser apparatus; a xenon adding unit that adds, to the regenerated gas, a third laser gas; and a control unit that controls, based on the supply amount, an addition amount of the third laser gas by the xenon adding unit.
    Type: Grant
    Filed: September 1, 2020
    Date of Patent: September 20, 2022
    Assignee: Gigaphoton Inc.
    Inventors: Hiroaki Tsushima, Satoshi Tanaka, Yousuke Fujimaki, Takeshi Asayama, Osamu Wakabayashi
  • Patent number: 11239625
    Abstract: A laser apparatus includes a controller that selects one of a first gas control and a second gas control based on gas pressure measured by a pressure sensor. The first gas control causes at least one of first laser gas and second laser gas is supplied to a chamber such that the gas pressure in the chamber after the first gas control is higher than the gas pressure in the chamber before the first gas control. The second gas control causes at least the first laser gas is supplied to the chamber and causes a part of the laser gas in the chamber is exhausted such that a difference between the gas pressure in the chamber before the second gas control and the gas pressure in the chamber after the second gas control is smaller than a difference between the gas pressure in the chamber before the first gas control and the gas pressure in the chamber after the first gas control.
    Type: Grant
    Filed: October 3, 2018
    Date of Patent: February 1, 2022
    Assignee: Gigaphoton Inc.
    Inventor: Takeshi Asayama
  • Patent number: 11079686
    Abstract: An excimer laser apparatus according to the present disclosure includes an etalon spectrometer configured to measure a fringe waveform of a laser beam; and a controller configured to obtain area of a first ratio in a spectral space obtained based on a result of the measurement by the etalon spectrometer, calculate a first spectral line width of the laser beam based on the obtained area of the first ratio, and calibrate a first spectral line width based on a correlation function representing correlation between the first spectral line width and a second spectral line width of the laser beam measured by a reference meter.
    Type: Grant
    Filed: May 11, 2020
    Date of Patent: August 3, 2021
    Assignee: Gigaphoton Inc.
    Inventors: Keisuke Ishida, Masato Moriya, Natsuhiko Kouno, Takeshi Asayama, Takashi Kusama
  • Patent number: 10971886
    Abstract: A laser apparatus includes a chamber accommodating a pair of discharge electrodes, a gas supply and exhaust device configured to supply laser gas to an interior of the chamber and exhaust laser gas from the interior of the chamber, and a controller. The controller performs first control to control the gas supply and exhaust device so as to suspend laser oscillation and replace laser gas in the chamber at every first number of pulses or first elapsed time, and second control to control the gas supply and exhaust device so as to suspend laser oscillation and replace laser gas in the chamber before the first control at every second number of pulses less than the first number of pulses or second elapsed time less than the first elapsed time.
    Type: Grant
    Filed: February 4, 2019
    Date of Patent: April 6, 2021
    Assignee: Gigaphoton Inc.
    Inventors: Takeshi Asayama, Hiroyuki Masuda
  • Patent number: 10965090
    Abstract: A laser apparatus according to the present disclosure includes: a laser chamber including a pair of electrodes and configured to emit, at each of a plurality of pulse repetition frequencies, a pulse laser beam having a pulse energy corresponding to a voltage applied between the electrodes; an energy detector provided on an optical path of the pulse laser beam and configured to detect the pulse energy of the pulse laser beam; a voltage control unit configured to control the applied voltage based on a target pulse energy and the pulse energy detected by the energy detector; and a pulse energy control unit configured to periodically vary the target pulse energy at a modulation frequency corresponding to each of the pulse repetition frequencies with a reference energy being a center of variation.
    Type: Grant
    Filed: May 3, 2019
    Date of Patent: March 30, 2021
    Assignee: Gigaphoton Inc.
    Inventor: Takeshi Asayama
  • Publication number: 20200403371
    Abstract: A laser gas regenerating apparatus regenerates a discharged gas discharged from at least one ArF excimer laser apparatus and supplies the regenerated gas to the at least one ArF excimer laser apparatus connected to a first laser gas supply source that supplies a first laser gas and to a second laser gas supply source that supplies a second laser gas. The laser gas regenerating apparatus includes a data obtaining unit that obtains data on a supply amount of the second laser gas supplied to the at least one ArF excimer laser apparatus; a xenon adding unit that adds, to the regenerated gas, a third laser gas; and a control unit that controls, based on the supply amount, an addition amount of the third laser gas by the xenon adding unit.
    Type: Application
    Filed: September 1, 2020
    Publication date: December 24, 2020
    Applicant: Gigaphoton Inc.
    Inventors: Hiroaki TSUSHIMA, Satoshi TANAKA, Yousuke FUJIMAKI, Takeshi ASAYAMA, Osamu WAKABAYASHI
  • Publication number: 20200274315
    Abstract: An excimer laser apparatus according to the present disclosure includes an etalon spectrometer configured to measure a fringe waveform of a laser beam; and a controller configured to obtain area of a first ratio in a spectral space obtained based on a result of the measurement by the etalon spectrometer, calculate a first spectral line width of the laser beam based on the obtained area of the first ratio, and calibrate a first spectral line width based on a correlation function representing correlation between the first spectral line width and a second spectral line width of the laser beam measured by a reference meter.
    Type: Application
    Filed: May 11, 2020
    Publication date: August 27, 2020
    Applicant: Gigaphoton Inc.
    Inventors: Keisuke ISHIDA, Masato MORIYA, Natsuhiko KOUNO, Takeshi ASAYAMA, Takashi KUSAMA
  • Publication number: 20190280451
    Abstract: A laser apparatus according to the present disclosure includes: a laser chamber including a pair of electrodes and configured to emit, at each of a plurality of pulse repetition frequencies, a pulse laser beam having a pulse energy corresponding to a voltage applied between the electrodes; an energy detector provided on an optical path of the pulse laser beam and configured to detect the pulse energy of the pulse laser beam; a voltage control unit configured to control the applied voltage based on a target pulse energy and the pulse energy detected by the energy detector; and a pulse energy control unit configured to periodically vary the target pulse energy at a modulation frequency corresponding to each of the pulse repetition frequencies with a reference energy being a center of variation.
    Type: Application
    Filed: May 3, 2019
    Publication date: September 12, 2019
    Applicant: Gigaphoton Inc.
    Inventor: Takeshi ASAYAMA
  • Publication number: 20190173259
    Abstract: A laser apparatus includes a chamber accommodating a pair of discharge electrodes, a gas supply and exhaust device configured to supply laser gas to an interior of the chamber and exhaust laser gas from the interior of the chamber, and a controller. The controller performs first control to control the gas supply and exhaust device so as to suspend laser oscillation and replace laser gas in the chamber at every first number of pulses or first elapsed time, and second control to control the gas supply and exhaust device so as to suspend laser oscillation and replace laser gas in the chamber before the first control at every second number of pulses less than the first number of pulses or second elapsed time less than the first elapsed time.
    Type: Application
    Filed: February 4, 2019
    Publication date: June 6, 2019
    Applicant: Gigaphoton Inc.
    Inventors: Takeshi ASAYAMA, Hiroyuki MASUDA
  • Publication number: 20190036290
    Abstract: A laser apparatus includes a controller that selects one of a first gas control and a second gas control based on gas pressure measured by a pressure sensor. The first gas control causes at least one of first laser gas and second laser gas is supplied to a chamber such that the gas pressure in the chamber after the first gas control is higher than the gas pressure in the chamber before the first gas control. The second gas control causes at least the first laser gas is supplied to the chamber and causes a part of the laser gas in the chamber is exhausted such that a difference between the gas pressure in the chamber before the second gas control and the gas pressure in the chamber after the second gas control is smaller than a difference between the gas pressure in the chamber before the first gas control and the gas pressure in the chamber after the first gas control.
    Type: Application
    Filed: October 3, 2018
    Publication date: January 31, 2019
    Applicant: Gigaphoton Inc.
    Inventor: Takeshi ASAYAMA
  • Patent number: 10177520
    Abstract: The excimer laser apparatus may include a laser chamber configured to contain gas, a pair of electrodes provided in the laser chamber, a power source unit configured to supply a pulse voltage between the pair of electrodes, a gas supply unit configured to supply gas into the laser chamber, a gas exhaust unit configured to partially exhaust gas from within the laser chamber, and a gas control unit configured to control the gas supply unit and the gas exhaust unit, where a replacement ratio of gas to be replaced from within the laser chamber increases as deterioration of the pair of electrodes progresses, the deterioration being represented by a deterioration parameter of the pair of electrodes.
    Type: Grant
    Filed: October 24, 2017
    Date of Patent: January 8, 2019
    Assignee: Gigaphoton Inc.
    Inventors: Takeshi Asayama, Osamu Wakabayashi, Kouji Kakizaki
  • Patent number: 10050403
    Abstract: An excimer laser chamber device may include: a the laser chamber; a first electrode provided in the laser chamber; a second electrode provided in the laser chamber to face the first electrode; an electrode holder provided in the laser chamber to be connected to a high voltage; at least one connecting terminal including a first anchored portion anchored to the first electrode and a second anchored portion anchored to the electrode holder, the at least one connecting terminal being configured to electrically connect the first electrode and the electrode holder; a guide member held by the electrode holder, the guide member being configured to position the first electrode in a direction substantially perpendicular to both a direction of electric discharge between the first electrode and the second electrode and a longitudinal direction of the first electrode; and an electrode-gap-varying unit configured to move the first electrode in a direction substantially parallel to the direction of electric discharge.
    Type: Grant
    Filed: August 18, 2017
    Date of Patent: August 14, 2018
    Assignee: Gigaphoton Inc.
    Inventors: Hisakazu Katsuumi, Kazuya Takezawa, Kouji Kakizaki, Hiroaki Tsushima, Takeshi Asayama
  • Patent number: 9991665
    Abstract: The laser system may include a delay circuit unit, first and second trigger-correction units, and a clock generator. The delay circuit unit may receive a trigger signal, output a first delay signal obtained by delaying the trigger signal by a first delay time, and output a second delay signal obtained by delaying the trigger signal by a second delay time. The first trigger-correction unit may receive the first delay signal and output a first switch signal obtained by delaying the first delay signal by a first correction time. The second trigger-correction unit may receive the second delay signal and output a second switch signal obtained by delaying the second delay signal by a second correction time. The clock generator may generate a clock signal that is common to the delay circuit unit and the first and second trigger-correction units.
    Type: Grant
    Filed: September 25, 2017
    Date of Patent: June 5, 2018
    Assignee: Gigaphoton Inc.
    Inventors: Hiroshi Umeda, Takeshi Asayama, Osamu Wakabayashi
  • Publication number: 20180048109
    Abstract: The excimer laser apparatus may include a laser chamber configured to contain gas, a pair of electrodes provided in the laser chamber, a power source unit configured to supply a pulse voltage between the pair of electrodes, a gas supply unit configured to supply gas into the laser chamber, a gas exhaust unit configured to partially exhaust gas from within the laser chamber, and a gas control unit configured to control the gas supply unit and the gas exhaust unit, where a replacement ratio of gas to be replaced from within the laser chamber increases as deterioration of the pair of electrodes progresses, the deterioration being represented by a deterioration parameter of the pair of electrodes.
    Type: Application
    Filed: October 24, 2017
    Publication date: February 15, 2018
    Applicant: Gigaphoton Inc.
    Inventors: Takeshi ASAYAMA, Osamu WAKABAYASHI, Kouji KAKIZAKI
  • Publication number: 20180013258
    Abstract: The laser system may include a delay circuit unit, first and second trigger-correction units, and a clock generator. The delay circuit unit may receive a trigger signal, output a first delay signal obtained by delaying the trigger signal by a first delay time, and output a second delay signal obtained by delaying the trigger signal by a second delay time. The first trigger-correction unit may receive the first delay signal and output a first switch signal obtained by delaying the first delay signal by a first correction time. The second trigger-correction unit may receive the second delay signal and output a second switch signal obtained by delaying the second delay signal by a second correction time. The clock generator may generate a clock signal that is common to the delay circuit unit and the first and second trigger-correction units.
    Type: Application
    Filed: September 25, 2017
    Publication date: January 11, 2018
    Applicant: Gigaphoton Inc.
    Inventors: Hiroshi UMEDA, Takeshi ASAYAMA, Osamu WAKABAYASHI
  • Patent number: 9853410
    Abstract: A gas laser apparatus includes a chamber containing a laser gas, a pair of electrodes disposed within the chamber, a fan disposed within the chamber, a motor connected to a rotating shaft of the fan, and a rotating speed control unit configured to control a rotating speed of the fan based on a wear-out parameter of the pair of electrodes.
    Type: Grant
    Filed: August 18, 2016
    Date of Patent: December 26, 2017
    Assignee: Gigaphoton Inc.
    Inventors: Takeshi Asayama, Hiroaki Tsushima, Kouji Kakizaki, Osamu Wakabayashi
  • Patent number: 9837780
    Abstract: The excimer laser apparatus may include a laser chamber configured to contain gas, a pair of electrodes provided in the laser chamber, a power source unit configured to supply a pulse voltage between the pair of electrodes, a gas supply unit configured to supply gas into the laser chamber, a gas exhaust unit configured to partially exhaust gas from within the laser chamber, and a gas control unit configured to control the gas supply unit and the gas exhaust unit, where a replacement ratio of gas to be replaced from within the laser chamber increases as deterioration of the pair of electrodes progresses, the deterioration being represented by a deterioration parameter of the pair of electrodes.
    Type: Grant
    Filed: May 10, 2016
    Date of Patent: December 5, 2017
    Assignee: Gigaphoton Inc.
    Inventors: Takeshi Asayama, Osamu Wakabayashi, Kouji Kakizaki
  • Publication number: 20170346252
    Abstract: An excimer laser chamber device may include: a the laser chamber; a first electrode provided in the laser chamber; a second electrode provided in the laser chamber to face the first electrode; an electrode holder provided in the laser chamber to be connected to a high voltage; at least one connecting terminal including a first anchored portion anchored to the first electrode and a second anchored portion anchored to the electrode holder, the at least one connecting terminal being configured to electrically connect the first electrode and the electrode holder; a guide member held by the electrode holder, the guide member being configured to position the first electrode in a direction substantially perpendicular to both a direction of electric discharge between the first electrode and the second electrode and a longitudinal direction of the first electrode; and an electrode-gap-varying unit configured to move the first electrode in a direction substantially parallel to the direction of electric discharge.
    Type: Application
    Filed: August 18, 2017
    Publication date: November 30, 2017
    Applicant: Gigaphoton Inc.
    Inventors: Hisakazu KATSUUMI, Kazuya TAKEZAWA, Kouji KAKIZAKI, Hiroaki TSUSHIMA, Takeshi ASAYAMA
  • Patent number: 9806490
    Abstract: The laser system may include a delay circuit unit, first and second trigger-correction units, and a clock generator. The delay circuit unit may receive a trigger signal, output a first delay signal obtained by delaying the trigger signal by a first delay time, and output a second delay signal obtained by delaying the trigger signal by a second delay time. The first trigger-correction unit may receive the first delay signal and output a first switch signal obtained by delaying the first delay signal by a first correction time. The second trigger-correction unit may receive the second delay signal and output a second switch signal obtained by delaying the second delay signal by a second correction time. The clock generator may generate a clock signal that is common to the delay circuit unit and the first and second trigger-correction units.
    Type: Grant
    Filed: November 17, 2016
    Date of Patent: October 31, 2017
    Assignee: Gigaphoton Inc.
    Inventors: Hiroshi Umeda, Takeshi Asayama, Osamu Wakabayashi