Patents by Inventor Tadashi Otaka

Tadashi Otaka 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: 7340111
    Abstract: Image evaluation method capable of objectively evaluating the image resolution of a microscope image. An image resolution method is characterized in that resolution in partial regions of an image is obtained over an entire area of the image or a portion of the image, averaging is performed over the entire area of the image or the portion of the image, and the averaged value is established as the resolution evaluation value of the entire area of the image or the portion of the image. This method eliminates the subjective impressions of the evaluator from evaluation of microscope image resolution, so image resolution evaluation values of high accuracy and good repeatability can be obtained.
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: March 4, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Ishitani, Mitsugu Sato, Hideo Todokoro, Tadashi Otaka, Takashi Iizumi, Atsushi Takane
  • Patent number: 7315024
    Abstract: An invention providing a scanning electron microscope composed of a monochromator capable of high resolution, monochromatizing the energy and reducing chromatic aberrations without significantly lowering the electrical current strength of the primary electron beam. A scanning electron microscope is installed with a pair of sectorial magnetic and electrical fields having opposite deflection directions to focus the electron beam and then limit the energy width by means of slits, and another pair of sectorial magnetic and electrical fields of the same shape is installed at a position forming a symmetrical mirror versus the surface containing the slits. This structure acts to cancel out energy dispersion at the object point and symmetrical mirror positions, and by spatially contracting the point-converged spot beam with a converging lens system, improves the image resolution of the scanning electron microscope.
    Type: Grant
    Filed: February 1, 2006
    Date of Patent: January 1, 2008
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Yoichi Ose, Shunroku Taya, Hideo Todokoro, Tadashi Otaka, Mitsugu Sato, Makoto Ezumi
  • Publication number: 20070280559
    Abstract: Image evaluation method capable of objectively evaluating the image resolution of a microscope image. An image resolution method is characterized in that resolution in partial regions of an image is obtained over an entire area of the image or a portion of the image, averaging is performed over the entire area of the image or the portion of the image, and the averaged value is established as the resolution evaluation value of the entire area of the image or the portion of the image. This method eliminates the subjective impressions of the evaluator from evaluation of microscope image resolution, so image resolution evaluation values of high accuracy and good repeatability can be obtained.
    Type: Application
    Filed: May 21, 2007
    Publication date: December 6, 2007
    Inventors: Tohru Ishitani, Mitsugu Sato, Hideo Todokoro, Tadashi Otaka, Takashi Iizumi, Atsushi Takane
  • Patent number: 7285777
    Abstract: An object of the present invention is to suppress measurement errors caused by the fact that the shrink amount due to scan of an electron beam differs pattern by pattern. To accomplish this object, according to the invention, functions indicative of a process of change of pattern dimension when the electron beam is irradiated on a sample are prepared in respect of the kinds of sample patterns, and dimension values of a particular pattern measured by scanning the electron beam on the particular pattern are fitted to a function prepared for the particular pattern to calculate a dimension of the particular pattern before it changes.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: October 23, 2007
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hiroki Kawada, Takashi Iizumi, Tadashi Otaka
  • Patent number: 7236651
    Abstract: Image evaluation method capable of objectively evaluating the image resolution of a microscope image. An image resolution method is characterized in that resolution in partial regions of an image is obtained over an entire area of the image or a portion of the image, averaging is performed over the entire area of the image or the portion of the image, and the averaged value is established as the resolution evaluation value of the entire area of the image or the portion of the image. This method eliminates the subjective impressions of the evaluator from evaluation of microscope image resolution, so image resolution evaluation values of high accuracy and good repeatability can be obtained.
    Type: Grant
    Filed: August 16, 2002
    Date of Patent: June 26, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Ishitani, Mitsugu Sato, Hideo Todokoro, Tadashi Otaka, Takashi Iizumi, Atsushi Takane
  • Publication number: 20070029478
    Abstract: An object of the present invention is to provide a sample image forming method and a charged particle beam apparatus which are suitable for realizing suppressing of the view area displacement with high accuracy while the influence of charging due to irradiation of the charged particle beam is being suppressed. In order to attain the above object, the present invention provide a method of forming a sample image by scanning a charged particle beam on a sample and forming an image based on secondary signals emitted from the sample, the method comprising the steps of forming a plurality of composite images by superposing a plurality of images obtained by a plurality of scanning times; and forming a further composite image by correcting positional displacements among the plurality of composite images and superposing the plurality of composite images, and a charged particle beam apparatus for realizing the above method.
    Type: Application
    Filed: August 9, 2006
    Publication date: February 8, 2007
    Inventors: Mitsugu Sato, Atsushi Takane, Takashi Iizumi, Tadashi Otaka, Hideo Todokoro, Satoru Yamaguchi, Kazutaka Nimura
  • Patent number: 7164126
    Abstract: An object of the present invention is to provide a sample image forming method and a charged particle beam apparatus which are suitable for realizing suppressing of the view area displacement with high accuracy while the influence of charging due to irradiation of the charged particle beam is being suppressed. In order to attain the above object, the present invention provide a method of forming a sample image by scanning a charged particle beam on a sample and forming an image based on secondary signals emitted from the sample, the method comprising the steps of forming a plurality of composite images by superposing a plurality of images obtained by a plurality of scanning times; and forming a further composite image by correcting positional displacements among the plurality of composite images and superposing the plurality of composite images, and a charged particle beam apparatus for realizing the above method.
    Type: Grant
    Filed: February 6, 2003
    Date of Patent: January 16, 2007
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Mitsugu Sato, Atsushi Takane, Takashi Iizumi, Tadashi Otaka, Hideo Todokoro, Satoru Yamaguchi, Kazutaka Nimura
  • Publication number: 20060269121
    Abstract: A system for measuring a pattern on a sample, including: a data processing system that processes a set of two-dimensional distribution data of intensities from the sample, to calculate: a set of edge points indicative of position of edges of said pattern in a two-dimensional plane from said two-dimensional distribution data; an approximation edge indicative of the edge of the pattern; an edge roughness data by calculating a difference between the set of edge points and said approximation edge; and a correlation between a first portion of the edge roughness data and a second portion of the edge roughness data.
    Type: Application
    Filed: August 10, 2006
    Publication date: November 30, 2006
    Inventors: Atsuko Yamaguchi, Tsuneo Terasawa, Tadashi Otaka, Takashi Iizumi, Osamu Komuro
  • Patent number: 7130063
    Abstract: A test pattern formed in a scribe line area of a wafer is irradiated with a light beam to measure the width thereof; the test pattern is irradiated with an electron beam so as to measure the width thereof; an amount of change in the width of the test pattern is calculated; a dummy pattern having the same width as that of a semiconductor device of the wafer is irradiated with an electron beam to measure the width thereof; and the width of a pattern is estimated by the use of the calculated amount of width change so as to determine the shape of the pattern. Thus, a shape measuring system and method capable of determining the shape of a micropattern in a semiconductor device without changing the dimensions of the micropattern can be provided.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: October 31, 2006
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Yasuhiro Mitsui, Yasutsugu Usami, Isao Kawata, Yuya Toyoshima, Tadashi Otaka, Nobuyuki Iriki
  • Publication number: 20060219910
    Abstract: An invention providing a scanning electron microscope composed of a monochromator capable of high resolution, monochromatizing the energy and reducing chromatic aberrations without significantly lowering the electrical current strength of the primary electron beam. A scanning electron microscope is installed with a pair of sectorial magnetic and electrical fields having opposite deflection directions to focus the electron beam and then limit the energy width by means of slits, and another pair of sectorial magnetic and electrical fields of the same shape is installed at a position forming a symmetrical mirror versus the surface containing the slits. This structure acts to cancel out energy dispersion at the object point and symmetrical mirror positions, and by spatially contracting the point-converged spot beam with a converging lens system, improves the image resolution of the scanning electron microscope.
    Type: Application
    Filed: February 1, 2006
    Publication date: October 5, 2006
    Inventors: Yoichi Ose, Shunroku Taya, Hideo Todokoro, Tadashi Otaka, Mitsugu Sato, Makoto Ezumi
  • Patent number: 7095884
    Abstract: The present invention provides a circuit pattern edge inspection method of finding out a failure in a fabricating process and image distortion in an observing apparatus by analyzing, by a non-destructive inspection, the shape of an edge of a line of a fine pattern in which characteristics of the material, process, and an exposure optical system in a semiconductor fabricating process appear, and performing analysis quantitatively. The method includes a step of detecting a set of edge points indicative of positions of edges of the pattern in a two-dimensional plane by a threshold method; a step of obtaining an approximation line for the set of edge points detected; and a step of obtaining an edge roughness shape and a characteristic by calculating the difference between the set of the edge points and the approximation line. A plurality of values are used as thresholds used for the threshold method.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: August 22, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Atsuko Yamaguchi, Tsuneo Terasawa, Tadashi Otaka, Takashi Iizumi, Osamu Komuro
  • Patent number: 7091496
    Abstract: Both wafers on which copper wiring was performed and wafers on which non-copper wiring was performed can be inspected by a single unit of electron microscopic inspection apparatus with no possibilities of the wafers being contaminated with copper. All elements within the apparatus that come in contact with wafers, such as hands of a wafer transporter, are duplicated or more and one of the elements that contact wafers is used appropriately for the wafers under inspection which may be either the wafers on which copper wiring was performed or the wafers on which non-copper wiring was performed.
    Type: Grant
    Filed: June 17, 2003
    Date of Patent: August 15, 2006
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Sho Takami, Tadashi Otaka, Manabu Shirakihara
  • Patent number: 7038767
    Abstract: A light beam is emitted to a test pattern place formed in the scribe area on the wafer for height measurement, an electron beam is emitted to the test pattern place for width and contrast measurement and their correlations are stored. The three-dimensional profile of a pattern in a semiconductor device on the wafer is determined by irradiating the pattern with an electron beam to measure the width and contrast and estimating the height of the pattern by inferring from a correlation corresponding to the measured width and contrast. Thus, a three-dimensional profile measuring system and method capable of measuring the three-dimensional profile of a micropattern in a semiconductor device without cutting the wafer are provided.
    Type: Grant
    Filed: November 7, 2002
    Date of Patent: May 2, 2006
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Yuya Toyoshima, Yasuhiro Mitsui, Yasutsugu Usami, Isao Kawata, Tadashi Otaka
  • Patent number: 7034296
    Abstract: An object of the present invention is to provide a sample image forming method and a charged particle beam apparatus which are suitable for realizing suppressing of the view area displacement with high accuracy while the influence of charging due to irradiation of the charged particle beam is being suppressed. In order to attain the above object, the present invention provide a method of forming a sample image by scanning a charged particle beam on a sample and forming an image based on secondary signals emitted from the sample, the method comprising the steps of forming a plurality of composite images by superposing a plurality of images obtained by a plurality of scanning times; and forming a further composite image by correcting positional displacements among the plurality of composite images and superposing the plurality of composite images, and a charged particle beam apparatus for realizing the above method.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: April 25, 2006
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Mitsugu Sato, Atsushi Takane, Takashi Iizumi, Tadashi Otaka, Hideo Todokoro, Satoru Yamaguchi, Kazutaka Nimura
  • Patent number: 7022983
    Abstract: An invention providing a scanning electron microscope composed of a monochromator capable of high resolution, monochromatizing the energy and reducing chromatic aberrations without significantly lowering the electrical current strength of the primary electron beam. A scanning electron microscope is installed with a pair of sectorial magnetic and electrical fields having opposite deflection directions to focus the electron beam and then limit the energy width by means of slits, and another pair of sectorial magnetic and electrical fields of the same shape is installed at a position forming a symmetrical mirror versus the surface containing the slits. This structure acts to cancel out energy dispersion at the object point and symmetrical mirror positions, and by spatially contracting the point-converged spot beam with a converging lens system, improves the image resolution of the scanning electron microscope.
    Type: Grant
    Filed: January 7, 2004
    Date of Patent: April 4, 2006
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Yoichi Ose, Shunroku Taya, Hideo Todokoro, Tadashi Otaka, Mitsugu Sato, Makoto Ezumi
  • Publication number: 20050247876
    Abstract: An object of the present invention is to suppress measurement errors caused by the fact that the shrink amount due to scan of an electron beam differs pattern by pattern. To accomplish this object, according to the invention, functions indicative of a process of change of pattern dimension when the electron beam is irradiated on a sample are prepared in respect of the kinds of sample patterns, and dimension values of a particular pattern measured by scanning the electron beam on the particular pattern are fitted to a function prepared for the particular pattern to calculate a dimension of the particular pattern before it changes.
    Type: Application
    Filed: May 19, 2003
    Publication date: November 10, 2005
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Hiroki Kawada, Takashi Iizumi, Tadashi Otaka
  • Publication number: 20050199811
    Abstract: Image evaluation method capable of objectively evaluating the image resolution of a microscope image. An image resolution method is characterized in that resolution in partial regions of an image is obtained over an entire area of the image or a portion of the image, averaging is performed over the entire area of the image or the portion of the image, and the averaged value is established as the resolution evaluation value of the entire area of the image or the portion of the image. This method eliminates the subjective impressions of the evaluator from evaluation of microscope image resolution, so image resolution evaluation values of high accuracy and good repeatability can be obtained.
    Type: Application
    Filed: May 9, 2005
    Publication date: September 15, 2005
    Inventors: Tohru Ishitani, Mitsugu Sato, Hideo Todokoro, Tadashi Otaka, Takashi Iizumi, Atsushi Takane
  • Patent number: 6933500
    Abstract: An electron microscope is provided, which enables an observation with high resolution. The electron microscope is able to detect the deviation of an electron beam relative to the opening of a slit quantitatively, thereby shifting the electron beam accurately to the center of the opening of slit so as to execute energy selection. The electron microscope has an energy filter control unit for adjusting a relative position between an electron beam and a slit by shifting the position of electron beam based on a signal delivered by an energy filter electron beam detector. Also a method for controlling an energy filter is provided, which includes the steps of shifting the position of an electron beam, determining the position of electron beam and letting the electron beam pass through the center of an opening of the slit by controlling the position of slit or position of electron beam.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: August 23, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Kazutoshi Kaji, Shohei Terada, Tadashi Otaka
  • Publication number: 20050182595
    Abstract: A test pattern formed in a scribe line area of a wafer is irradiated with a light beam to measure the width thereof; the test pattern is irradiated with an electron beam so as to measure the width thereof; an amount of change in the width of the test pattern is calculated; a dummy pattern having the same width as that of a semiconductor device of the wafer is irradiated with an electron beam to measure the width thereof; and the width of a pattern is estimated by the use of the calculated amount of width change so as to determine the shape of the pattern. Thus, a shape measuring system and method capable of determining the shape of a micropattern in a semiconductor device without changing the dimensions of the micropattern can be provided.
    Type: Application
    Filed: April 11, 2005
    Publication date: August 18, 2005
    Inventors: Yasuhiro Mitsui, Yasutsugu Usami, Isao Kawata, Yuya Toyoshima, Tadashi Otaka, Nobuyuki Iriki
  • Publication number: 20050167589
    Abstract: An electron microscope is provided, which enables an observation with high resolution. The electron microscope is able to detect the deviation of an electron beam relative to the opening of a slit quantitatively, thereby shifting the electron beam accurately to the center of the opening of slit so as to execute energy selection. The electron microscope has an energy filter control unit for adjusting a relative position between an electron beam and a slit by shifting the position of electron beam based on a signal delivered by an energy filter electron beam detector. Also a method for controlling an energy filter is provided, which includes the steps of shifting the position of an electron beam, determining the position of electron beam and letting the electron beam pass through the center of an opening of the slit by controlling the position of slit or position of electron beam.
    Type: Application
    Filed: March 28, 2005
    Publication date: August 4, 2005
    Inventors: Kazutoshi Kaji, Shohei Terada, Tadashi Otaka