Patents by Inventor Stephen E. Savas

Stephen E. Savas 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: 20240071754
    Abstract: Plasma processing apparatus and associated methods are provided. In one example, a plasma processing apparatus includes a plasma chamber. The plasma processing apparatus includes a dielectric wall forming at least a portion of the plasma chamber. The plasma processing apparatus includes an inductive coupling element located proximate the dielectric wall. The plasma processing apparatus includes an ultraviolet light source configured to emit an ultraviolet light beam onto a metal surface that faces an interior volume of the plasma chamber. The plasma processing apparatus includes a controller configured to control the ultraviolet light source.
    Type: Application
    Filed: November 7, 2023
    Publication date: February 29, 2024
    Inventors: Stephen E. Savas, Shawming Ma
  • Patent number: 11887820
    Abstract: A radio frequency plasma processing system including a reaction chamber, an electrode having an electrode symmetry axis, the electrode disposed in the reaction chamber, and a plurality of plates, each having an electrically conducting layer, disposed in the reaction chamber azimuthally with respect to the electrode symmetry axis around a perimeter of the electrode at a gap from the electrode surface, each of the plurality of plates connected to an electrical ground through a variable reactance circuit.
    Type: Grant
    Filed: January 8, 2021
    Date of Patent: January 30, 2024
    Assignee: COMET TECHNOLOGIES USA, INC.
    Inventors: Stephen E. Savas, Alexandre De Chambrier
  • Patent number: 11848204
    Abstract: Plasma processing apparatus and associated methods are provided. In one example, a plasma processing apparatus includes a plasma chamber. The plasma processing apparatus includes a dielectric wall forming at least a portion of the plasma chamber. The plasma processing apparatus includes an inductive coupling element located proximate the dielectric wall. The plasma processing apparatus includes an ultraviolet light source configured to emit an ultraviolet light beam onto a metal surface that faces an interior volume of the plasma chamber. The plasma processing apparatus includes a controller configured to control the ultraviolet light source.
    Type: Grant
    Filed: May 27, 2022
    Date of Patent: December 19, 2023
    Assignees: Beijing E-Town Semiconductor Technology Co., Ltd, Mattson Technology, Inc.
    Inventors: Stephen E. Savas, Shawming Ma
  • Patent number: 11830708
    Abstract: A broad-band sensor for a radio frequency plasma processing system that includes a reaction chamber housing an electrode within a vacuum processing environment. The sensor includes an inductive pickup positioned in the vacuum processing environment proximate to the electrode. The inductive pickup includes a wire formed into a loop extending in an azimuthal direction about a symmetry axis of the reaction chamber. A lead carrying an electric signal from the inductive pickup extends through a vacuum wall of the reaction chamber outside the vacuum processing environment. An attenuator circuit including an electrical resistance bridge couples the lead to a signal carrier extending outside the vacuum processing environment. The broad-band sensor has radio frequency detection capability for measuring electromagnetic surface modes within the plasma chamber and coupling the measured electromagnetic surface modes to the signal carrier.
    Type: Grant
    Filed: January 8, 2021
    Date of Patent: November 28, 2023
    Assignee: COMET TECHNOLOGIES USA, INC.
    Inventors: Stephen E. Savas, Alexandre De Chambrier
  • Publication number: 20230260755
    Abstract: A method of detecting plasma asymmetry in a radio frequency plasma processing system, the method including providing a radio frequency power to a reaction chamber having an approximate chamber symmetry axis and receiving from a plurality of broadband electromagnetic sensors a radio frequency signal. The method also including processing the radio frequency signals using Fourier analysis and determining based on the Fourier analysis of the radio frequency signals that a plasma asymmetry has occurred within the reaction chamber.
    Type: Application
    Filed: April 25, 2023
    Publication date: August 17, 2023
    Applicant: COMET TECHNOLOGIES USA, INC.
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER
  • Patent number: 11670488
    Abstract: A method of detecting plasma asymmetry in a radio frequency plasma processing system, the method including providing a radio frequency power to a reaction chamber having an approximate chamber symmetry axis and receiving from a plurality of broadband electromagnetic sensors a radio frequency signal. The method also including processing the radio frequency signals using Fourier analysis and determining based on the Fourier analysis of the radio frequency signals that a plasma asymmetry has occurred within the reaction chamber.
    Type: Grant
    Filed: January 8, 2021
    Date of Patent: June 6, 2023
    Assignee: COMET TECHNOLOGIES USA, INC.
    Inventors: Stephen E. Savas, Alexandre De Chambrier
  • Patent number: 11605527
    Abstract: A method of controlling a radio frequency processing system, the method including determining an end time of a radio frequency pulse; stopping a load applied to the radio frequency processing system based on the end time of the radio frequency pulse; adjusting an additional load having a predetermined impedance applied to the radio frequency processing system in response to the determined end time; determining a start point of a second radio frequency pulse; and stopping the additional load before the second radio frequency pulse occurs.
    Type: Grant
    Filed: January 19, 2021
    Date of Patent: March 14, 2023
    Assignee: COMET TECHNOLOGIES USA, INC.
    Inventors: Alexandre De Chambrier, Stephen E. Savas
  • Patent number: 11521832
    Abstract: A radio frequency plasma processing system including a reaction chamber, a pedestal disposed in the reaction chamber, and a plurality of sector plates disposed azimuthally around the pedestal in an annulus between the pedestal and the reaction chamber.
    Type: Grant
    Filed: January 8, 2021
    Date of Patent: December 6, 2022
    Assignee: COMET TECHNOLOGIES USA, INC.
    Inventors: Stephen E. Savas, Alexandre De Chambrier
  • Publication number: 20220310359
    Abstract: Plasma processing apparatus and associated methods are provided. In one example, a plasma processing apparatus includes a plasma chamber. The plasma processing apparatus includes a dielectric wall forming at least a portion of the plasma chamber. The plasma processing apparatus includes an inductive coupling element located proximate the dielectric wall. The plasma processing apparatus includes an ultraviolet light source configured to emit an ultraviolet light beam onto a metal surface that faces an interior volume of the plasma chamber. The plasma processing apparatus includes a controller configured to control the ultraviolet light source.
    Type: Application
    Filed: May 27, 2022
    Publication date: September 29, 2022
    Inventors: Stephen E. Savas, Shawming Ma
  • Patent number: 11348784
    Abstract: Plasma processing apparatus and associated methods are provided. In one example, a plasma processing apparatus includes a plasma chamber. The plasma processing apparatus includes a dielectric wall forming at least a portion of the plasma chamber. The plasma processing apparatus includes an inductive coupling element located proximate the dielectric wall. The plasma processing apparatus includes an ultraviolet light source configured to emit an ultraviolet light beam onto a metal surface that faces an interior volume of the plasma chamber. The plasma processing apparatus includes a controller configured to control the ultraviolet light source.
    Type: Grant
    Filed: August 22, 2019
    Date of Patent: May 31, 2022
    Assignees: BEIJING E-TOWN SEMICONDUCTOR TECHNOLOGY CO., LTD, MATTSON TECHNOLOGY, INC.
    Inventors: Stephen E. Savas, Shawming Ma
  • Publication number: 20220165614
    Abstract: Plasma processing systems and methods are provided. In one example, a system includes a processing chamber having a workpiece support. The workpiece is configured to support a workpiece. The system includes a plasma source configured to induce a plasma from a process gas in a plasma chamber to generate one or more species of negative ions. The system includes a grid structure configured to accelerate the one or more negative ions towards the workpiece. The grid structure can include a first grid plate, a second grid plate, and one or more magnetic elements positioned between the first grid plate and second grid plate to reduce electrons accelerated through the first grid plate. The system can include a neutralizer cell disposed. downstream of the grid structure configured to detach extra electrons from ions of the one or more species of negative ions to generate energetic neutral species for processing the workpiece.
    Type: Application
    Filed: February 14, 2022
    Publication date: May 26, 2022
    Inventor: Stephen E. Savas
  • Publication number: 20220084792
    Abstract: Plasma processing apparatus and associated methods are provided. In one example, a plasma processing apparatus can include a plasma chamber configured to be able to hold a plasma. The plasma processing apparatus can include a dielectric window forming at least a portion of a wall of the plasma chamber. The plasma processing apparatus can include an inductive coupling element located proximate the dielectric window. The inductive coupling element can be configured to generate a plasma from the process gas in the plasma chamber when energized with radio frequency (RF) energy. The plasma processing apparatus can include a processing chamber having a workpiece support configured to support a workpiece. The plasma processing apparatus can include an electrostatic shield located between the inductive coupling element and the dielectric window. The electrostatic shield can be grounded via a tunable reactive impedance circuit to a ground reference.
    Type: Application
    Filed: November 29, 2021
    Publication date: March 17, 2022
    Inventors: Stephen E. Savas, Shawming Ma
  • Patent number: 11251075
    Abstract: Plasma processing systems and methods are provided. In one example, a system includes a processing chamber having a workpiece support. The workpiece is configured to support a workpiece. The system includes a plasma source configured to induce a plasma from a process gas in a plasma chamber to generate one or more species of negative ions. The system includes a grid structure configured to accelerate the one or more negative ions towards the workpiece. The grid structure can include a first grid plate, a second grid plate, and one or more magnetic elements positioned between the first grid plate and second grid plate to reduce electrons accelerated through the first grid plate. The system can include a neutralizer cell disposed downstream of the grid structure configured to detach extra electrons from ions of the one or more species of negative ions to generate energetic neutral species for processing the workpiece.
    Type: Grant
    Filed: August 6, 2018
    Date of Patent: February 15, 2022
    Assignees: Mattson Technology, Inc., Beijing E-Town Semiconductor Technology Co., Ltd.
    Inventor: Stephen E. Savas
  • Patent number: 11189464
    Abstract: Plasma processing apparatus and associated methods are provided. In one example, a plasma processing apparatus can include a plasma chamber configured to be able to hold a plasma. The plasma processing apparatus can include a dielectric window forming at least a portion of a wall of the plasma chamber. The plasma processing apparatus can include an inductive coupling element located proximate the dielectric window. The inductive coupling element can be configured to generate a plasma from the process gas in the plasma chamber when energized with radio frequency (RF) energy. The plasma processing apparatus can include a processing chamber having a workpiece support configured to support a workpiece. The plasma processing apparatus can include an electrostatic shield located between the inductive coupling element and the dielectric window. The electrostatic shield can be grounded via a tunable reactive impedance circuit to a ground reference.
    Type: Grant
    Filed: July 17, 2019
    Date of Patent: November 30, 2021
    Assignees: Beijing E-Town Semiconductor Technology Co., Ltd., Mattson Technology, Inc.
    Inventors: Stephen E. Savas, Shawming Ma
  • Publication number: 20210225613
    Abstract: A method of controlling a radio frequency processing system, the method including determining an end time of a radio frequency pulse; stopping a load applied to the radio frequency processing system based on the end time of the radio frequency pulse; adjusting an additional load having a predetermined impedance applied to the radio frequency processing system in response to the determined end time; determining a start point of a second radio frequency pulse; and stopping the additional load before the second radio frequency pulse occurs.
    Type: Application
    Filed: January 19, 2021
    Publication date: July 22, 2021
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER
  • Publication number: 20210217589
    Abstract: A radio frequency plasma processing system including a reaction chamber, a pedestal disposed in the reaction chamber, and a plurality of sector plates disposed azimuthally around the pedestal in an annulus between the pedestal and the reaction chamber.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER
  • Publication number: 20210217593
    Abstract: A radio frequency plasma processing system including a reaction chamber, an electrode having an electrode symmetry axis, the electrode disposed in the reaction chamber, and a plurality of plates, each having an electrically conducting layer, disposed in the reaction chamber azimuthally with respect to the electrode symmetry axis around a perimeter of the electrode at a gap from the electrode surface, each of the plurality of plates connected to an electrical ground through a variable reactance circuit.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER
  • Publication number: 20210217587
    Abstract: A method of detecting non-uniformity in a plasma in a radio frequency plasma processing system, the method including generating a plasma within a reaction chamber of the radio frequency plasma processing system and detecting electrical signals from the plasma in a frequency range from a frequency of radio frequency power sustaining the plasma to a multiple of about ten times a frequency with a plurality of sensors disposed azimuthally about a chamber symmetry axis of the radio frequency plasma processing system. The method also including comparing the waveforms of the electrical signals picked up from the plasma by the plurality of sensors and determining when a plasma non-uniformity occurs based on the comparing the electrical property of the plasma detected by each of the plurality of sensors.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER
  • Publication number: 20210217590
    Abstract: A method of detecting plasma asymmetry in a radio frequency plasma processing system, the method including providing a radio frequency power to a reaction chamber having an approximate chamber symmetry axis and receiving from a plurality of broadband electromagnetic sensors a radio frequency signal. The method also including processing the radio frequency signals using Fourier analysis and determining based on the Fourier analysis of the radio frequency signals that a plasma asymmetry has occurred within the reaction chamber.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER
  • Publication number: 20210217588
    Abstract: A radio frequency plasma processing system including a reaction chamber having an approximate chamber symmetry axis, a first plasma powering device, and a plurality of azimuthally disposed broadband electromagnetic sensors located approximately equidistant from the chamber symmetry axis to measure electromagnetic behavior about the reaction chamber during a radio frequency plasma process.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: STEPHEN E. SAVAS, ALEXANDRE DE CHAMBRIER