Patents by Inventor Mitsunori Ohata

Mitsunori Ohata 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: 20240071734
    Abstract: There is provided a lower electrode mechanism for plasma processing, the lower electrode mechanism including: a base portion to which radio-frequency power is applied during the plasma processing; a dielectric portion disposed at an upper surface of the base portion; and an induction heating mechanism, in which the induction heating mechanism includes an induction heating element heated by an induction magnetic field, and a magnetic field generator that is disposed inside the base portion and generates the induction magnetic field.
    Type: Application
    Filed: October 25, 2023
    Publication date: February 29, 2024
    Inventors: Naoki MATSUMOTO, Mitsunori OHATA, Masataka MASUYAMA, Naoki MIHARA
  • Patent number: 11915910
    Abstract: A method of plasma processing includes generating a glow phase of an electropositive plasma in a plasma processing chamber containing a first species, a second species, and a substrate comprising a major surface and generating an electronegative plasma in an afterglow phase of the electropositive plasma in the plasma processing chamber by combining the electrons of the electropositive plasma with atoms or molecules of the second species. The electropositive plasma includes positive ions of the first species and electrons. The electronegative plasma includes the positive ions and negative ions of the second species. The method further includes, in the afterglow phase, cyclically performing steps of generating neutral particles by applying a negative bias voltage at the substrate and applying a non-negative bias voltage at the substrate. The average velocity of the neutral particles is towards and substantially normal to the major surface of the substrate.
    Type: Grant
    Filed: March 25, 2021
    Date of Patent: February 27, 2024
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Peter Ventzek, Mitsunori Ohata, Alok Ranjan
  • Publication number: 20240014006
    Abstract: A plasma processing apparatus includes: a plasma processing apparatus includes: a plasma processing chamber; a substrate support; a source RF generator coupled to the plasma processing chamber, and configured to generate a source RF pulsed signal; a first bias RF generator configured to generate a first bias RF pulsed signal; a second bias RF generator configured to generate a second bias RF pulsed signal; a first separation circuit connected between the first bias RF generator and the substrate support, and configured to suppress a coupling of the second bias RF pulsed signal from the second bias RF generator to the first bias RF generator, and a second separation circuit connected between the second bias RF generator and the substrate support, and configured to suppress a coupling of the first bias RF pulsed signal from the first bias RF generator to the second bias RF generator.
    Type: Application
    Filed: September 25, 2023
    Publication date: January 11, 2024
    Applicant: Tokyo Electron Limited
    Inventors: Naoki FUJIWARA, Mitsunori OHATA, Takahiro TAKEUCHI
  • Publication number: 20230377849
    Abstract: A method of processing a substrate that includes: loading the substrate in a plasma processing chamber, the substrate including an underlying layer; maintaining a steady state flow of a process gas into the plasma processing chamber in the plasma processing chamber; generating a plasma in the plasma processing chamber; exposing the substrate to the plasma to etch the underlying layer; and pulsing a first additional gas, using a first effusive gas injector, towards a first region of the substrate to disrupt the steady state flow of the process gas over the first region, the pulsing locally changing a composition of the plasma near the first region.
    Type: Application
    Filed: June 15, 2022
    Publication date: November 23, 2023
    Inventors: Shyam Sridhar, Ya-Ming Chen, Peter Lowell George Ventzek, Mitsunori Ohata, Alok Ranjan
  • Publication number: 20230377853
    Abstract: A plasma etching system for a substrate including: a plasma processing chamber; a substrate holder disposed in the plasma processing chamber; a RF power source configured to generate a plasma in the plasma processing chamber; a set of electromagnets configured to apply a magnetic field in the processing chamber, the magnetic field of the set of the electromagnets being independent from a magnetic field generated by the RF power source; and a microprocessor coupled to the RF power source and the set of electromagnets, the microprocessor including a non-volatile memory having a program including instructions to: power the RF power source and generate the plasma in the processing chamber to etch the substrate; and provide a power pulse train to the set of electromagnets and generate the magnetic field that is pulsed, in the plasma processing chamber.
    Type: Application
    Filed: June 16, 2022
    Publication date: November 23, 2023
    Inventors: Ya-Ming Chen, Shyam Sridhar, Peter Lowell George Ventzek, Alok Ranjan, Mitsunori Ohata
  • Patent number: 11817295
    Abstract: A method of plasma processing includes performing a reactive species control phase, performing an ion/radical control phase, and performing a by-product control phase. The reactive species control phase includes pulsing source power to a processing chamber to generate ions and radicals in a plasma. The ion/radical control phase is performed after the reactive species control phase. The ion/radical control phase includes reducing the source power to the processing chamber and pulsing bias power to a substrate in the processing chamber. The by-product control phase is performed after the ion/radical control phase. The by-product control phase includes reducing the source power to the processing chamber relative to the reactive species control phase and reducing the bias power to the substrate relative to the ion/radical control phase.
    Type: Grant
    Filed: August 14, 2019
    Date of Patent: November 14, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Peter Ventzek, Alok Ranjan, Mitsunori Ohata
  • Patent number: 11798787
    Abstract: A plasma processing apparatus includes: a source RF generator that generates a source RF pulsed signal of at least three power levels; first and second bias RF generators that generate first and second bias RF pulsed signals of at least two power levels; a synchronization signal generator that generates a synchronization signal; a first matching circuit connected to the source RF generator and an antenna, thereby allowing the source RF pulsed signal to be supplied from the source RF generator to the antenna through the first matching circuit; and a second matching circuit connected to the first and second bias RF generators and a substrate support, thereby allowing the first and second bias RF pulse signals to be supplied from the first and second bias RF generators to the substrate support through the second matching circuit.
    Type: Grant
    Filed: August 23, 2021
    Date of Patent: October 24, 2023
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Naoki Fujiwara, Mitsunori Ohata, Takahiro Takeuchi
  • Publication number: 20230187214
    Abstract: A method of etching a substrate that includes: generating a first plasma from a first gas flowing into a first chamber by applying a first power pulse to a first electrode located in the first chamber over a first time duration; and forming a recess in a substrate located in a second chamber, the forming including: providing radicals from the first chamber into the second chamber; applying a plurality of second power pulses to a second electrode located in the second chamber during a second time duration to generate a second plasma in the second chamber from a second gas flowing into the second chamber, the first chamber being pressurized higher than the second chamber; and applying a plurality of third power pulses to a third electrode located in the second chamber during a third time duration to accelerate ions of the second plasma.
    Type: Application
    Filed: December 14, 2021
    Publication date: June 15, 2023
    Inventors: Peter Lowell George Ventzek, Alok Ranjan, Mitsunori Ohata
  • Publication number: 20220392749
    Abstract: A plasma processing apparatus includes a plasma processing chamber, a source power coupling element configured to generate plasma in an interior of the plasma processing chamber by coupling source power to the plasma processing chamber, a DC pulse generator configured to generate a DC pulse train at a DC pulse frequency, a substrate holder disposed in the interior of the plasma processing chamber, a DC coupling element coupled to the DC pulse generator, a DC current path including the DC coupling element, the plasma, and a reference potential node in a series configuration, the DC coupling element being configured to bias the substrate holder relative to the reference potential node using the DC pulse train, and a capacitive pre-coat layer disposed between the DC coupling element and the plasma. The capacitive pre-coat layer increases the RC time constant of the DC current path according to the DC pulse frequency.
    Type: Application
    Filed: June 2, 2021
    Publication date: December 8, 2022
    Inventors: Peter Lowell George Ventzek, Mitsunori Ohata, Alok Ranjan, Yun Han
  • Patent number: 11521834
    Abstract: A plasma processing system includes a radical source chamber including a gas inlet, an electrode coupled to a radio frequency (RF) power source, where the electrode is configured to generate radicals within the radical source chamber, and an exit for radicals generated within the radical source chamber; a plenum attached to the exit of the radical source chamber, where the plenum is made of a first thermal conductor, and where the walls of the plenum include openings for gas flow; and a process chamber connected to the radical source chamber through the plenum. The process chamber includes a substrate holder disposed below the plenum; a gas outlet below the substrate holder; and process chamber walls including a second thermal conductor, where the process chamber walls of the process chamber are thermally coupled to the walls of the plenum.
    Type: Grant
    Filed: August 26, 2020
    Date of Patent: December 6, 2022
    Assignee: Tokyo Electron Limited
    Inventors: Peter Ventzek, Alok Ranjan, Mitsunori Ohata
  • Publication number: 20220310357
    Abstract: A method of plasma processing includes generating a glow phase of an electropositive plasma in a plasma processing chamber containing a first species, a second species, and a substrate comprising a major surface and generating an electronegative plasma in an afterglow phase of the electropositive plasma in the plasma processing chamber by combining the electrons of the electropositive plasma with atoms or molecules of the second species. The electropositive plasma includes positive ions of the first species and electrons. The electronegative plasma includes the positive ions and negative ions of the second species. The method further includes, in the afterglow phase, cyclically performing steps of generating neutral particles by applying a negative bias voltage at the substrate and applying a non-negative bias voltage at the substrate. The average velocity of the neutral particles is towards and substantially normal to the major surface of the substrate.
    Type: Application
    Filed: March 25, 2021
    Publication date: September 29, 2022
    Inventors: Peter Ventzek, Mitsunori Ohata, Alok Ranjan
  • Publication number: 20220301834
    Abstract: A plasma processing apparatus includes a plasma processing chamber, a substrate support disposed in the plasma processing chamber, an annular baffle plate disposed so as to surround the substrate support, the annular baffle plate having a plurality of openings, a first annular plate disposed below the annular baffle plate, a second annular plate disposed below the first annular plate, the second annular plate having an annular overlapping portion vertically overlapping with a part of the first annular plate, a pressure detector configured to detect a pressure in the plasma processing chamber, and at least one actuator configured to vertically move at least one of the first and second annular plates so as to change a distance between the first annular plate and the second annular plate based on the detected pressure.
    Type: Application
    Filed: March 16, 2022
    Publication date: September 22, 2022
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Hwajun JUNG, Mitsunori Ohata, Yuki Hosaka, Wan Sung Jin
  • Patent number: 11450515
    Abstract: An apparatus includes a plasma processing container; a workpiece placement table disposed in the plasma processing container; a dielectric member having a facing surface that faces the workpiece placement table; an antenna provided on a surface of the dielectric member opposite to the facing surface and configured to introduce an induced electric field for plasma excitation into the plasma processing container via the dielectric member; an electromagnet group disposed along an outer circumference of the plasma processing container and configured to form a magnetic field in the plasma processing container; and a controller configured to control magnitudes of electric currents flowing through respective electromagnets of the electromagnet group differently from each other, to generate a magnetic gradient along a circumferential direction in the magnetic field that exists only in an outer circumferential space in the plasma processing container.
    Type: Grant
    Filed: September 24, 2020
    Date of Patent: September 20, 2022
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Kazuya Nagaseki, Shinji Himori, Mitsunori Ohata
  • Publication number: 20220102119
    Abstract: A plasma processing apparatus comprising a processing chamber, a dielectric, an antenna, and a first to third electromagnet groups is disclosed. In the processing chamber, a mounting table having a mounting surface is included and a plasma process is performed. A surface of the dielectric faces the mounting surface. The antenna, provided on the opposite surface of the dielectric, introduces an electric field into the processing table through the dielectric to form plasma. The first electromagnet group, provided at a position higher than the mounting surface on an outer perimeter of the processing chamber, forms a first magnetic field above the mounting surface. The second electromagnet group, provided inside the mounting table along an outer perimeter thereof, and the third electromagnet group, provided at a position corresponding to the second electromagnet group on the outer perimeter of the processing chamber, cooperate with each other to form a second magnetic field around the mounting surface.
    Type: Application
    Filed: September 24, 2021
    Publication date: March 31, 2022
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Hwajun JUNG, Mitsunori OHATA, Yuki HOSAKA
  • Publication number: 20220068601
    Abstract: A plasma processing system includes a radical source chamber including a gas inlet, an electrode coupled to a radio frequency (RF) power source, where the electrode is configured to generate radicals within the radical source chamber, and an exit for radicals generated within the radical source chamber; a plenum attached to the exit of the radical source chamber, where the plenum is made of a first thermal conductor, and where the walls of the plenum include openings for gas flow; and a process chamber connected to the radical source chamber through the plenum. The process chamber includes a substrate holder disposed below the plenum; a gas outlet below the substrate holder; and process chamber walls including a second thermal conductor, where the process chamber walls of the process chamber are thermally coupled to the walls of the plenum.
    Type: Application
    Filed: August 26, 2020
    Publication date: March 3, 2022
    Inventors: Peter Ventzek, Alok Ranjan, Mitsunori Ohata
  • Publication number: 20220068605
    Abstract: A plasma processing apparatus includes: a source RF generator that generates a source RF pulsed signal of at least three power levels; first and second bias RF generators that generate first and second bias RF pulsed signals of at least two power levels; a synchronization signal generator that generates a synchronization signal; a first matching circuit connected to the source RF generator and an antenna, thereby allowing the source RF pulsed signal to be supplied from the source RF generator to the antenna through the first matching circuit; and a second matching circuit connected to the first and second bias RF generators and a substrate support, thereby allowing the first and second bias RF pulse signals to be supplied from the first and second bias RF generators to the substrate support through the second matching circuit.
    Type: Application
    Filed: August 23, 2021
    Publication date: March 3, 2022
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Naoki FUJIWARA, Mitsunori OHATA, Takahiro TAKEUCHI
  • Patent number: 11251021
    Abstract: A plasma processing apparatus includes a plasma processing chamber, a coil having an uncoiled length L disposed adjacent to the plasma processing chamber, and a plurality of retractable conductors each configured to make electrical contact with the coil in an extended position. A first tap position is located substantially at a distance L/2 measured from a first end along the coil, a second tap position neighboring the first tap position and located substantially at the distance L/2 measured from the first end along the coil, and a third tap position located substantially at the first end of the coil. A controller is configured to operate the plasma processing apparatus in a first operating mode to sustain an inductively coupled plasma and in a second operating mode to sustain a capacitively coupled plasma using subsets of the retractable conductors in the extended position.
    Type: Grant
    Filed: January 29, 2021
    Date of Patent: February 15, 2022
    Assignee: TOKYO ELECTRON LIMITED
    Inventors: Peter Ventzek, Alok Ranjan, Mitsunori Ohata, Michael Hummel
  • Publication number: 20220028695
    Abstract: A plasma processing apparatus includes a processing chamber, a source power coupling element configured to generate plasma in the processing chamber, and a source power supply node coupled to the source power coupling element and configured to supply radio frequency power to the source power coupling element. The plasma processing apparatus further includes a substrate holder disposed in the processing chamber, a first bias power supply node coupled to the substrate holder and configured to supply first direct current biased power to the substrate holder, and a second bias power supply node coupled to the substrate holder and configured to supply second direct current biased power to the substrate holder. The first direct current biased power includes a first bias power frequency less than about 800 kHz and the second direct current biased power includes a second bias power frequency greater than 800 kHz.
    Type: Application
    Filed: September 23, 2021
    Publication date: January 27, 2022
    Inventors: Alok Ranjan, Peter Ventzek, Mitsunori Ohata
  • Publication number: 20210384013
    Abstract: A plasma processing apparatus includes a plasma processing chamber; a substrate support disposed in the plasma processing chamber and including an electrostatic chuck; a first ring disposed on the electrostatic chuck to surround a substrate on the electrostatic chuck and including an inner annular portion, an intermediate annular portion, and an outer annular portion, a top surface of the inner annular portion being higher than that of the intermediate annular portion, a top surface of the outer annular portion being higher than that of the inner annular portion; a second ring disposed on the intermediate annular portion; and an actuator configured to vertically move the second ring to maintain a top surface of the second ring at a first height greater than a height of the top surface of the inner annular portion and less than a height of the top surface of the outer annular portion.
    Type: Application
    Filed: June 4, 2021
    Publication date: December 9, 2021
    Inventors: Hwajun Jung, Masahiro Suzuki, Yuki Hosaka, Mitsunori Ohata
  • Publication number: 20210358716
    Abstract: A plasma processing apparatus includes: a plasma processing chamber; a substrate support disposed in the plasma processing chamber and including a lower electrode; a source RF generator coupled to the plasma processing chamber and configured to generate a source RF signal including high states and low states in alternate manner; and a bias DC generator coupled to the lower electrode and configured to generate a bias DC signal including ON states and OFF states in alternate manner. Each ON state includes a plurality of cycles, each cycle including a first sequence of first pulses and a second sequence of second pulses, each first pulse having a first voltage level, and each second pulse having a second voltage level different from the first voltage level.
    Type: Application
    Filed: May 7, 2021
    Publication date: November 18, 2021
    Applicant: TOKYO ELECTRON LIMITED
    Inventors: Bongseong KIM, Ken KOBAYASHI, Mitsunori OHATA, Yoon Ho BAE