Patents by Inventor Kenji Mitomo

Kenji Mitomo 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: 8949043
    Abstract: While an illumination optical system is irradiating the surface of a contaminated standard wafer with illumination light, this illumination light is scanned over the surface of the contaminated standard wafer, then detectors of a detection optical system each detect the light scattered from the surface of the contaminated standard wafer, next a predefined reference value in addition to detection results on the scattered light is used to calculate a compensation parameter “Comp” for detection sensitivity correction of photomultiplier tubes of the detectors, and the compensation parameter “Comp” is separated into a time-varying deterioration parameter “P”, an optical characteristics parameter “Opt”, and a sensor characteristics parameter “Lr”, and correspondingly managed. This makes is easy to calibrate the detection sensitivity.
    Type: Grant
    Filed: February 2, 2010
    Date of Patent: February 3, 2015
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Kenji Oka, Kenji Mitomo, Kenichiro Komeda
  • Patent number: 8804108
    Abstract: This application relates to an inspection apparatus including: a stage which holds a specimen; an illumination optical system which illuminates a surface of the specimen held on the stage, with illumination light; a dark-field optical system which detects scattered light generated by the illumination light with which the specimen is illuminated; a photoelectric converter which converts the scattered light detected by the dark-field optical system, into an electric signal; an A/D converter which converts the electric signal obtained by conversion by the photoelectric converter, into a digital signal; a judgement unit which determines the dimension of a foreign substance on the surface of the specimen on the basis of a magnitude of the scattered light from the foreign substance; and a signal processor which determines an inspection condition by use of information on the scattered light from the specimen surface.
    Type: Grant
    Filed: December 4, 2009
    Date of Patent: August 12, 2014
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Kenji Mitomo, Kenji Oka
  • Publication number: 20120050729
    Abstract: Technical Problem In the method of determining an inspection condition while measuring a signal in the dark-field inspection apparatus or the like, it takes time to produce the inspection condition, and the judgement as to the appropriateness of a sensitivity condition which is set is influenced by the operator's discretion.
    Type: Application
    Filed: December 4, 2009
    Publication date: March 1, 2012
    Inventors: Kenji Mitomo, Kenji Oka
  • Publication number: 20120046884
    Abstract: While an illumination optical system 2 is irradiating the surface of a contaminated standard wafer 110 with illumination light, this illumination light is scanned over the surface of the contaminated standard wafer 110, then detectors 31 to 34 of a detection optical system 3 each detect the light scattered from the surface of the contaminated standard wafer 110, next a predefined reference value in addition to detection results on the scattered light is used to calculate a compensation parameter “Comp” for detection sensitivity correction of photomultiplier tubes 331 to 334 of the detectors 31 to 34, and the compensation parameter “Comp” is separated into a time-varying deterioration parameter “P”, an optical characteristics parameter “Opt”, and a sensor characteristics parameter “Lr”, and correspondingly managed. This makes it easy to calibrate the detection sensitivity.
    Type: Application
    Filed: February 2, 2010
    Publication date: February 23, 2012
    Applicant: Hitachi High-Technologies Corporation
    Inventors: Kenji Oka, Kenji Mitomo, Kenichiro Komeda
  • Patent number: 7864310
    Abstract: When measuring an edge region, a photo detector with an angle not influenced by the diffracted light, the diffracted light causing noise, is selected to thereby allow for inspection that minimizes the sensitivity reduction. This allows for the management of foreign matters in the outer peripheral portion, which conventionally could not be measured, and this also eliminates the oversight of critical defects on the wafer, thus leading to reduction of failures of IC.
    Type: Grant
    Filed: October 9, 2009
    Date of Patent: January 4, 2011
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Takashi Okawa, Kenji Mitomo
  • Publication number: 20100026996
    Abstract: When measuring an edge region, a photo detector with an angle not influenced by the diffracted light, the diffracted light causing noise, is selected to thereby allow for inspection that minimizes the sensitivity reduction. This allows for the management of foreign matters in the outer peripheral portion, which conventionally could not be measured, and this also eliminates the oversight of critical defects on the wafer, thus leading to reduction of failures of IC.
    Type: Application
    Filed: October 9, 2009
    Publication date: February 4, 2010
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Takashi Okawa, Kenji Mitomo
  • Patent number: 7616299
    Abstract: When measuring an edge region, a photo detector with an angle not influenced by the diffracted light, the diffracted light causing noise, is selected to thereby allow for inspection that minimizes the sensitivity reduction. This allows for the management of foreign matters in the outer peripheral portion, which conventionally could not be measured, and this also eliminates the oversight of critical defects on the wafer, thus leading to reduction of failures of IC.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: November 10, 2009
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Takashi Okawa, Kenji Mitomo
  • Publication number: 20080007727
    Abstract: When measuring an edge region, a photo detector with an angle not influenced by the diffracted light, the diffracted light causing noise, is selected to thereby allow for inspection that minimizes the sensitivity reduction. This allows for the management of foreign matters in the outer peripheral portion, which conventionally could not be measured, and this also eliminates the oversight of critical defects on the wafer, thus leading to reduction of failures of IC.
    Type: Application
    Filed: July 6, 2007
    Publication date: January 10, 2008
    Inventors: Takashi Okawa, Kenji Mitomo
  • Patent number: 6798504
    Abstract: Light beam is irradiated onto a surface of a substrate to be inspected and scattered lights from the surface of the substrate are received at different light reception angles, so that first and second light detection signals corresponding to the different light reception angles are generated. Reference function defining a correlation in level value between the first and second light detection signals is set, a comparison is made between respective level values of the first and second light detection signals using the reference function as a comparison reference, and it is determined, on the basis of a result of the comparison, which of a plurality of different types of defects, such as a foreign substance and crystal-originated pit, a possible defect present on the surface of the substrate, which is represented by the light detection signals, corresponds to.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: September 28, 2004
    Assignee: Hitachi High-Tech Electronics Engineering Co., Ltd.
    Inventors: Tatsuya Sato, Yuichiro Kato, Kenji Mitomo
  • Patent number: 6731384
    Abstract: An apparatus and method for detecting foreign particle and defect on an object in detection by means of a laser beam, in which the laser beams of different wavelengths are irradiated onto the surface of the object in detection from different angles and the state of foreign particle and defect is separately detected according to the output level of the scattered light reflected from that surface. Further, it is arranged such that the scattered light reflected from the object onto which the laser beam is irradiated from the sole source or the plurality of sources is detected in plural directions, which detecting result is compared for the detection of the directivity of said scattered light in reflection.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: May 4, 2004
    Assignees: Hitachi, Ltd., Hitachi Electronics Engineering Co., Ltd.
    Inventors: Yoshimasa Ohshima, Minori Noguchi, Hidetoshi Nishiyama, Kenji Mitomo, Takashi Okawa, Akira Hamamatsu, Shinichi Suzuki
  • Publication number: 20020041374
    Abstract: An apparatus and method for detecting foreign particle and defect on an object in detection by means of a laser beam, in which the laser beams of different wavelengths are irradiated onto the surface of the object in detection from different angles and the state of foreign particle and defect is separately detected according to the output level of the scattered light reflected from that surface. Further, it is arranged such that the scattered light reflected from the object onto which the laser beam is irradiated from the sole source or the plurality of sources is detected in plural directions, which detecting result is compared for the detection of the directivity of said scattered light in reflection.
    Type: Application
    Filed: October 10, 2001
    Publication date: April 11, 2002
    Inventors: Yoshimasa Ohshima, Minori Noguchi, Hidetoshi Nishiyama, Kenji Mitomo, Takashi Okawa, Akira Hamamatsu, Shinichi Suzuki
  • Publication number: 20020036771
    Abstract: Light beam is irradiated onto a surface of a substrate to be inspected and scattered lights from the surface of the substrate are received at different light reception angles, so that first and second light detection signals corresponding to the different light reception angles are generated. Reference function defining a correlation in level value between the first and second light detection signals is set, a comparison is made between respective level values of the first and second light detection signals using the reference function as a comparison reference, and it is determined, on the basis of a result of the comparison, which of a plurality of different types of defects, such as a foreign substance and crystal-originated pit, a possible defect present on the surface of the substrate, which is represented by the light detection signals, corresponds to.
    Type: Application
    Filed: September 24, 2001
    Publication date: March 28, 2002
    Applicant: HITACHI ELECTRONICS ENGINEERING CO., LTD.
    Inventors: Tatsuya Sato, Yuichiro Kato, Kenji Mitomo