Patents by Inventor Kensaku IGARASHI

Kensaku IGARASHI 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: 12272542
    Abstract: A method for cleaning a semiconductor silicon wafer including: an ozone water treatment step after polishing in ozone water, a step of performing a first ultrasonic-wave-ozone-water treatment of cleaning at room temperature while immersing in ozone water and applying ultrasonic waves; and a step of performing a second ultrasonic-wave-ozone-water treatment of, after the step of performing the first ultrasonic-wave-ozone-water treatment, pulling out the semiconductor silicon wafer from the ozone water, performing rotation process, and cleaning at room temperature while immersing in ozone water and applying ultrasonic waves; wherein the step of performing the second ultrasonic-wave-ozone-water treatment is performed, and a hydrofluoric acid treatment step and an ozone water treatment step are performed.
    Type: Grant
    Filed: September 17, 2019
    Date of Patent: April 8, 2025
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Kensaku Igarashi
  • Patent number: 11878329
    Abstract: A method for cleaning a silicon wafer includes the steps of: supplying hydrofluoric acid onto a surface of the silicon wafer to treat the silicon wafer while rotating at a first rotational rate, stopping the supply of the hydrofluoric acid and shaking off hydrofluoric acid on the surface of the silicon wafer without supplying pure water onto the surface of the silicon wafer while rotating the silicon wafer at a second rotational rate which is the same as or faster than the first rotational rate, and supplying ozone water onto the surface of the silicon wafer to treat the silicon wafer after shaking the hydrofluoric acid off the surface while rotating at a third rotational rate which is faster than the second rotational rate. This method for cleaning a silicon wafer is capable of suppressing adhesion of water marks and particles and enhancing the wafer quality.
    Type: Grant
    Filed: July 31, 2018
    Date of Patent: January 23, 2024
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku Igarashi, Tatsuo Abe
  • Patent number: 11862456
    Abstract: A method for cleaning a semiconductor wafer to clean a semiconductor wafer after polishing, including: performing a first ozone-water treatment step of cleaning the polished semiconductor wafer with ozone water to form an oxide film; performing a brush cleaning step of brush-cleaning the semiconductor wafer with carbonated water after the first ozone-water treatment step; and then performing a second ozone-water treatment step including cleaning the semiconductor wafer with hydrofluoric acid to remove the oxide film, followed by cleaning with ozone water to form an oxide film again. This second ozone-water treatment step is performed one or more times.
    Type: Grant
    Filed: February 18, 2021
    Date of Patent: January 2, 2024
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Kensaku Igarashi
  • Publication number: 20230154742
    Abstract: A method for cleaning a semiconductor wafer to clean a semiconductor wafer after polishing, including: performing a first ozone-water treatment step of cleaning the polished semiconductor wafer with ozone water to form an oxide film; performing a brush cleaning step of brush-cleaning the semiconductor wafer with carbonated water after the first ozone-water treatment step; and then performing a second ozone-water treatment step including cleaning the semiconductor wafer with hydrofluoric acid to remove the oxide film, followed by cleaning with ozone water to form an oxide film again. This second ozone-water treatment step is performed one or more times. The method for cleaning a semiconductor wafer achieves cleaning level equivalent to that with SC1, reduces or prevents defect generation on a wafer surface and surface roughness degradation which would otherwise occur when SC1 is used, and also results in cost reduction and environmental load reduction.
    Type: Application
    Filed: February 18, 2021
    Publication date: May 18, 2023
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Kensaku IGARASHI
  • Publication number: 20220059343
    Abstract: A method for cleaning a semiconductor silicon wafer including: an ozone water treatment step after polishing in ozone water, a step of performing a first ultrasonic-wave-ozone-water treatment of cleaning at room temperature while immersing in ozone water and applying ultrasonic waves; and a step of performing a second ultrasonic-wave-ozone-water treatment of, after the step of performing the first ultrasonic-wave-ozone-water treatment, pulling out the semiconductor silicon wafer from the ozone water, performing rotation process, and cleaning at room temperature while immersing in ozone water and applying ultrasonic waves; wherein the step of performing the second ultrasonic-wave-ozone-water treatment is performed, and a hydrofluoric acid treatment step and an ozone water treatment step are performed.
    Type: Application
    Filed: September 17, 2019
    Publication date: February 24, 2022
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Kensaku IGARASHI
  • Patent number: 11222780
    Abstract: A method for evaluating a silicon wafer, including: a pre surface defect measuring step for performing a surface defect measurement on the silicon wafer in advance, a cleaning step of alternately repeating on the silicon wafer an oxidation treatment by ozone water and an oxide film removal treatment by hydrofluoric acid under a condition of not completely removing an oxide film formed on a surface of the silicon wafer, and an incremental defect measuring step of performing a surface defect measurement on the silicon wafer after the cleaning step and measuring incremental defects that increased relative to defects measured in the pre surface defect measuring step, wherein the cleaning step and the incremental defect measuring step are alternately performed repeatedly multiple times and the silicon wafer is evaluated based on a measurement result of the incremental defects after each cleaning step.
    Type: Grant
    Filed: August 20, 2018
    Date of Patent: January 11, 2022
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku Igarashi, Tatsuo Abe
  • Patent number: 11177125
    Abstract: A method for cleaning a semiconductor wafer, including: inserting a semiconductor wafer into a hydrofluoric acid tank filled with hydrofluoric acid to immerse the semiconductor wafer in the hydrofluoric acid; pulling out the semiconductor wafer from the hydrofluoric acid tank; and then inserting the semiconductor wafer into an ozone water tank filled with ozone water to immerse the semiconductor wafer in the ozone water for cleaning. The semiconductor wafer is inserted into the ozone water tank at a rate of 20000 mm/min or more at least after a lower end of the semiconductor wafer comes into contact with the ozone water until the semiconductor wafer is completely immersed in the ozone water. A method for cleaning a semiconductor wafer which can prevent and remove contaminant from re-adhering in a method in which a semiconductor wafer is cleaned by immersion in hydrofluoric acid and then cleaned by immersion in ozone water.
    Type: Grant
    Filed: March 5, 2018
    Date of Patent: November 16, 2021
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku Igarashi, Tatsuo Abe
  • Patent number: 11094525
    Abstract: A method for cleaning a semiconductor wafer, including: supplying a semiconductor wafer whose surface has an oxide film formed thereon with a cleaning solution capable of removing the oxide film; and cleaning, while rotating, the semiconductor wafer to remove the oxide film formed on the surface of the semiconductor wafer. The oxide film is removed such that a rotational speed of the semiconductor wafer is 300 rpm or more after the cleaning with the cleaning solution is started and before a water-repelling surface is attained, and then the rotational speed of the semiconductor wafer is changed to 100 rpm or less to completely remove the oxide film. A method for cleaning a semiconductor wafer by which both surface roughness improvement and surface defect suppression can be achieved.
    Type: Grant
    Filed: December 20, 2017
    Date of Patent: August 17, 2021
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku Igarashi, Tatsuo Abe
  • Publication number: 20210013031
    Abstract: A wafer treatment apparatus with a rotatable table inside a chamber and a plurality of holding pins arranged on the table, where a periphery of a wafer is held by the plurality of holding pins and the wafer is subjected to a cleaning and/or drying treatment while being rotated, where one or more of the plurality of holding pins are drivable, and press and hold the wafer so that a resultant force working on the held wafer works in a direction that bends the wafer upwards in a convex shape. A wafer treatment apparatus and a method for treating a wafer that can prevent particles from aggregating in a wafer rotation center and prevent dry marks, etc. from occurring.
    Type: Application
    Filed: February 26, 2019
    Publication date: January 14, 2021
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku IGARASHI, Tatsuo ABE
  • Publication number: 20200203233
    Abstract: A method for evaluating a silicon wafer, including: a pre surface defect measuring step for performing a surface defect measurement on the silicon wafer in advance, a cleaning step of alternately repeating on the silicon wafer an oxidation treatment by ozone water and an oxide film removal treatment by hydrofluoric acid under a condition of not completely removing an oxide film formed on a surface of the silicon wafer, and an incremental defect measuring step of performing a surface defect measurement on the silicon wafer after the cleaning step and measuring incremental defects that increased relative to defects measured in the pre surface defect measuring step, wherein the cleaning step and the incremental defect measuring step are alternately performed repeatedly multiple times and the silicon wafer is evaluated based on a measurement result of the incremental defects after each cleaning step.
    Type: Application
    Filed: August 20, 2018
    Publication date: June 25, 2020
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku IGARASHI, Tatsuo ABE
  • Publication number: 20200164410
    Abstract: A method for cleaning a silicon wafer includes the steps of: supplying hydrofluoric acid onto a surface of the silicon wafer to treat the silicon wafer while rotating at a first rotational rate, stopping the supply of the hydrofluoric acid and shaking off hydrofluoric acid on the surface of the silicon wafer without supplying pure water onto the surface of the silicon wafer while rotating the silicon wafer at a second rotational rate which is the same as or faster than the first rotational rate, and supplying ozone water onto the surface of the silicon wafer to treat the silicon wafer after shaking the hydrofluoric acid off the surface while rotating at a third rotational rate which is faster than the second rotational rate. This method for cleaning a silicon wafer is capable of suppressing adhesion of water marks and particles and enhancing the wafer quality.
    Type: Application
    Filed: July 31, 2018
    Publication date: May 28, 2020
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku IGARASHI, Tatsuo ABE
  • Publication number: 20200105517
    Abstract: A method for cleaning a semiconductor wafer, including: supplying a semiconductor wafer whose surface has an oxide film formed thereon with a cleaning solution capable of removing the oxide film; and cleaning, while rotating, the semiconductor wafer to remove the oxide film formed on the surface of the semiconductor wafer. The oxide film is removed such that a rotational speed of the semiconductor wafer is 300 rpm or more after the cleaning with the cleaning solution is started and before a water-repelling surface is attained, and then the rotational speed of the semiconductor wafer is changed to 100 rpm or less to completely remove the oxide film. A method for cleaning a semiconductor wafer by which both surface roughness improvement and surface defect suppression can be achieved.
    Type: Application
    Filed: December 20, 2017
    Publication date: April 2, 2020
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku IGARASHI, Tatsuo ABE
  • Publication number: 20200027721
    Abstract: A method for cleaning a semiconductor wafer, including: inserting a semiconductor wafer into a hydrofluoric acid tank filled with hydrofluoric acid to immerse the semiconductor wafer in the hydrofluoric acid; pulling out the semiconductor wafer from the hydrofluoric acid tank; and then inserting the semiconductor wafer into an ozone water tank filled with ozone water to immerse the semiconductor wafer in the ozone water for cleaning. The semiconductor wafer is inserted into the ozone water tank at a rate of 20000 mm/min or more at least after a lower end of the semiconductor wafer comes into contact with the ozone water until the semiconductor wafer is completely immersed in the ozone water. A method for cleaning a semiconductor wafer which can prevent and remove contaminant from re-adhering in a method in which a semiconductor wafer is cleaned by immersion in hydrofluoric acid and then cleaned by immersion in ozone water.
    Type: Application
    Filed: March 5, 2018
    Publication date: January 23, 2020
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Kensaku IGARASHI, Tatsuo ABE