Patents by Inventor Hiroya Ohta

Hiroya Ohta 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: 6784442
    Abstract: This invention provides a multi-charged-particle beam exposure apparatus capable of easily correcting at a high precision the electron-optic characteristics of each column which constitutes an electron-optic system. The exposure apparatus has magnetic lens arrays (ML1, ML2, ML3, and ML4) which commonly adjust the electron-optic characteristics of a plurality of columns which constitute the electron-optic system, and dynamic focus lenses or deflector arrays which individually correct the electron-optic characteristics of the columns.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: August 31, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masato Muraki, Hiroya Ohta, Shin-ichi Hashimoto
  • Patent number: 6768118
    Abstract: The present invention provides a beam monitoring sensor which can offer both high beam monitoring precision and high speed monitoring in a multi-electron beam writing system and a monitoring method using the same. In a Faraday cup for electron beam monitoring, tantalum or a heavy metal material having an atomic number larger than that of tantalum is used to provide a Faraday cup construction having a high aspect ratio. The micro Faraday cup permits electron beam monitoring having less beam leak to a high acceleration electron beam.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: July 27, 2004
    Assignees: Hitachi, Ltd., Canon Kabushiki Kaisha, Advantest Corporation
    Inventors: Yoshinori Nakayama, Yasunari Sohda, Hiroya Ohta, Norio Saitou, Masato Muraki, Masaki Takakuwa
  • Publication number: 20040143356
    Abstract: The dimension of the main field as a unit region for exposure is set to an integral submultiple of the arrangement pitch of the LSI to be exposed, by the control computer 62, and the exposure data stored in the form associated with electron beams from a data generation circuit 64 is limited to one-chip data alone in units of a stripe. This data is repeatedly read out to write the stripe. Further, a storage circuit 66 is provided to store the exposure data by means of a double buffer memory unit for each electron beam. While LSI is written according to one of the buffers, the next exposure stripe data is prepared on the other buffer, thereby bringing about a substantial reduction in the required speed of the exposure data generation circuit.
    Type: Application
    Filed: July 30, 2003
    Publication date: July 22, 2004
    Inventors: Haruo Yoda, Yasunari Souda, Hiroya Ohta, Yoshikiyo Yui, Shinichi Hashimoto
  • Publication number: 20040129898
    Abstract: There is provided an electron beam wiring technique which can correct deflection for a micro field used in electron beam writing equipment with high precision.
    Type: Application
    Filed: July 30, 2003
    Publication date: July 8, 2004
    Inventors: Yasunari Sohda, Hiroya Ohta, Osamu Kamimura, Susumu Gotoh
  • Publication number: 20040119026
    Abstract: There is provided an electron beam exposure technique which permits optical adjustment in an electron optics system using a doublet lens necessary for large field projection.
    Type: Application
    Filed: August 6, 2003
    Publication date: June 24, 2004
    Inventors: Yasunari Sohda, Osamu Kamimura, Hiroya Ohta, Susumu Gotoh
  • Publication number: 20040056578
    Abstract: This invention provides a multielectron gun which generates a plurality of electron beams having uniform characteristics. A multielectron gun (2) is formed of a plurality of electron guns (2a-2c). The electron gun (2a) has, in addition to an electron source (21a), Wehnelt electrode (22a), and anode electrode (23), a shield electrode (24) between the Wehnelt electrode (22a) and anode electrode (23). The shield electrode reduces field interference among the electron guns.
    Type: Application
    Filed: July 14, 2003
    Publication date: March 25, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masahiko Okunuki, Hiroya Ohta, Norio Saito, Masaki Takakuwa, Sayaka Tanimoto, Takeshi Haraguchi
  • Publication number: 20040026627
    Abstract: The present invention provides a beam monitoring sensor which can offer both high beam monitoring precision and high speed monitoring in a multi-electron beam writing system and a monitoring method using the same.
    Type: Application
    Filed: January 24, 2003
    Publication date: February 12, 2004
    Inventors: Yoshinori Nakayama, Yasunari Sohda, Hiroya Ohta, Norio Saitou, Masato Muraki, Masaki Takakuwa
  • Patent number: 6667486
    Abstract: The present invention provides a high-precision and high-speed electron beam exposure technique which corrects the position of each beam in a multi-beam exposure method without using a deflection array and a huge and high-precision driving circuit. In an electron beam exposure method for forming a desired pattern onto a specimen by independently controlling emission and scanning of a plurality of electron beams, a deviation between a pattern formed by each of the plurality of electron beams and the desired pattern is controlled by shifting the position of pattern data of the pattern formed by each of the plurality of electron beams.
    Type: Grant
    Filed: August 16, 2002
    Date of Patent: December 23, 2003
    Assignees: Hitachi, Ltd., Canon Kabushiki Kaisha, Advantest Corporation
    Inventors: Hiroya Ohta, Yasunari Sohda, Norio Saitou, Haruo Yoda, Yoshikiyo Yui, Shin'ichi Hashimoto
  • Publication number: 20030189181
    Abstract: The present invention provides a high-precision and high-speed electron beam exposure technique which corrects the position of each beam in a multi-beam exposure method without using a deflection array and a huge and high-precision driving circuit. In an electron beam exposure method for forming a desired pattern onto a specimen by independently controlling emission and scanning of a plurality of electron beams, a deviation between a pattern formed by each of the plurality of electron beams and the desired pattern is controlled by shifting the position of pattern data of the pattern formed by each of the plurality of electron beams.
    Type: Application
    Filed: August 16, 2002
    Publication date: October 9, 2003
    Inventors: Hiroya Ohta, Yasunari Sohda, Norio Saitou, Haruo Yoda, Yoshikiyo Yui, Shin?apos;ichi Hashimoto
  • Publication number: 20030122087
    Abstract: This invention provides a multi-charged-particle beam exposure apparatus capable of easily correcting at a high precision the electron-optic characteristics of each column which constitutes an electron-optic system. The exposure apparatus has magnetic lens arrays (ML1, ML2, ML3, and ML4) which commonly adjust the electron-optic characteristics of a plurality of columns which constitute the electron-optic system, and dynamic focus lenses or deflector arrays which individually correct the electron-optic characteristics of the columns.
    Type: Application
    Filed: December 27, 2002
    Publication date: July 3, 2003
    Inventors: Masato Muraki, Hiroya Ohta, Shin-ichi Hashimoto
  • Patent number: 6511048
    Abstract: An electron beam lithography apparatus and a semiconductor device pattern forming method for precisely writing patterns near the periphery of a cell mask so that large scale integrated circuits and fine structure devices are fabricated at high yield rates. Cell figures with lower aperture rates are located peripherally and cell figures with higher aperture rates are located closer to a central portion within each of aperture groups furnished on a second mask of the inventive apparatus adopting cell projection. Illustratively, on a mask for use in semiconductor device fabrication, cell figures for forming line patterns and gate patterns are located centrally and cell figures for forming hole patterns are positioned peripherally in each aperture group. This allows the peripherally located figures to be written precisely in each aperture group.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: January 28, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yasunari Sohda, Yasuhiro Someda, Hiroya Ohta, Takashi Matsuzaka, Norio Saitou, Yoshinori Nakayama
  • Patent number: 6159644
    Abstract: In a semiconductor circuit device fabricating process in which a reduction image projection exposure apparatus and an electron beam exposure apparatus are in a mixed use in its exposure process, pattern position shift errors for each exposure apparatus are measured and corrected at the time of drawing by means of an electron beam drawing apparatus, thereby enhancing the alignment accuracy.First, a pattern for measuring position shifts is exposed using a stepper and the electron beam drawing apparatus. Then, the position shift errors are measured using an identical coordinate position measuring device. Accidental errors have been mixed in the measurement result at this time. On account of this, measurement data at a certain point are smoothed by taking a summation average with data on the periphery thereof, thus decreasing influences of the accidental errors. Moreover, by inverting positive or negative signs of the data on the position shift errors, the data are made into correction data.
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: December 12, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Hidetoshi Satoh, Yoshinori Nakayama, Masahide Okumura, Hiroya Ohta, Norio Saitou
  • Patent number: 5326979
    Abstract: An electron beam lithography system which generates phase shift pattern data relating to main patterns, and exposes the phase shift pattern on a mask plate by using an electron beam in accordance with instruction from a computer. An electron beam lithography system is provided which can remarkably decrease a time needed for preparing phase shift pattern data. The apparatus is furnished with a parameter table for storing equations to generate phase shift pattern data, and generates the phase shift pattern data by assigning original pattern data into equations in accordance with a corresponding instruction for applying a phase shift method, and automatically exposes the phase shift pattern.
    Type: Grant
    Filed: September 25, 1992
    Date of Patent: July 5, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiro Kawasaki, Takashi Matsuzaka, Hiroya Ohta, Toshihiko Kohno