Patents by Inventor Katsuhiro Sasada

Katsuhiro Sasada 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: 10393509
    Abstract: A pattern height measurement device capable of high-precision measurement of the dimensions of a fine pattern, and a charged particle beam device are provided. The pattern height measurement device includes a calculation device that determines dimensions of a sample, in the height direction, based on first reflected light information obtained by dispersing light reflected from a sample. The calculation device determines second reflected light information based on a formula for the relationship between the value for the dimension in the sample surface direction of a pattern formed upon the sample, obtained by irradiation of a charged particle beam on the sample, the value for the dimension in the height direction of the sample, and reflected light information; compares a second reflected light intensity and the first reflected light information; and outputs the value for the dimension in the height direction of the sample in the second reflected light information.
    Type: Grant
    Filed: July 30, 2014
    Date of Patent: August 27, 2019
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hiroki Kawada, Katsuhiro Sasada, Takenori Hirose, Shou Takami
  • Patent number: 10184790
    Abstract: The presently disclosed subject matter provides a pattern measurement method and device for achieving highly accurate measurement in the depth direction of a pattern. The method involves a focused ion beam irradiated to form an inclined surface in a sample area; a field of view of a SEM set to include the boundary between the inclined surface and a sample surface; and an image of the field of view obtained on the basis of a detection signal. Such an acquired image is used to specify a first position, the boundary between inclined surface and non-inclined surface, and a second position, the position of a desired deep hole or deep groove positioned within the inclined surface. The pattern dimension in a height direction is determined on the basis of the distance in the sample surface direction between the first position and second position and the angle of the inclined surface.
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: January 22, 2019
    Assignee: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Hiroki Kawada, Hideo Sakai, Katsuhiro Sasada
  • Publication number: 20170211929
    Abstract: A purpose of the present invention is to provide: a pattern height measurement device capable of high-precision measurement of the dimensions of a fine pattern, in the height direction; and a charged particle beam device. In order to achieve the purpose, this pattern height measurement device comprises a calculation device that finds the dimensions of a sample, in the height direction, on the basis of first reflected light information obtained by dispersing light that is reflected when the sample is irradiated with light.
    Type: Application
    Filed: July 30, 2014
    Publication date: July 27, 2017
    Inventors: Hiroki KAWADA, Katsuhiro SASADA, Takenori HIROSE, Shou TAKAMI
  • Patent number: 9671223
    Abstract: Beforehand, the device characteristic patterns of each critical dimension SEM are measured, a sectional shape of an object to undergo dimension measurement is presumed by a model base library (MBL) matching system, dimension measurements are carried out by generating signal waveforms through SEM simulation by inputting the presumed sectional shapes and the device characteristic parameters, and differences in the dimension measurement results are registered as machine differences. In actual measurements, from the dimension measurement results in each critical dimension SEM, machine differences are corrected by subtracting the registered machine differences. Furthermore, changes in critical dimension SEM's over time are monitored by periodically measuring the above-mentioned device characteristic parameters and predicting the above-mentioned dimension measurement results. According to the present invention, actual measurements of machine differences, which require considerable time and effort, are unnecessary.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: June 6, 2017
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Chie Shishido, Maki Tanaka, Katsuhiro Sasada
  • Publication number: 20170138725
    Abstract: The presently disclosed subject matter provides a pattern measurement method and device for achieving highly accurate measurement in the depth direction of a pattern. The method involves a focused ion beam irradiated to form an inclined surface in a sample area; a field of view of a SEM set to include the boundary between the inclined surface and a sample surface; and an image of the field of view obtained on the basis of a detection signal. Such an acquired image is used to specify a first position, the boundary between inclined surface and non-inclined surface, and a second position, the position of a desired deep hole or deep groove positioned within the inclined surface. The pattern dimension in a height direction is determined on the basis of the distance in the sample surface direction between the first position and second position and the angle of the inclined surface.
    Type: Application
    Filed: May 11, 2015
    Publication date: May 18, 2017
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Hiroki Kawada, Hideo Sakai, Katsuhiro Sasada
  • Publication number: 20150235804
    Abstract: A charged particle microscope system with a charged particle microscope including an irradiation unit that irradiates a subject to be inspected with a charged particle beam and a detection unit having a detector that detects a charged particle signal from the subject to be inspected irradiated by the irradiation unit; a signal processing unit that converts the charged particle signal detected by the detector of the charged particle microscope into an image signal; and an arithmetic processing unit that corrects the image signal converted by the signal processing unit with the use of signal conversion characteristics.
    Type: Application
    Filed: August 7, 2013
    Publication date: August 20, 2015
    Inventors: Mayuka Osaki, Maki Kimura, Chie Shishido, Katsuhiro Sasada
  • Publication number: 20130166240
    Abstract: Beforehand, the device characteristic patterns of each critical dimension SEM are measured, a sectional shape of an object to undergo dimension measurement is presumed by a model base library (MBL) matching system, dimension measurements are carried out by generating signal waveforms through SEM simulation by inputting the presumed sectional shapes and the device characteristic parameters, and differences in the dimension measurement results are registered as machine differences. In actual measurements, from the dimension measurement results in each critical dimension SEM, machine differences are corrected by subtracting the registered machine differences. Furthermore, changes in critical dimension SEM's over time are monitored by periodically measuring the above-mentioned device characteristic parameters and predicting the above-mentioned dimension measurement results. According to the present invention, actual measurements of machine differences, which require considerable time and effort, are unnecessary.
    Type: Application
    Filed: May 20, 2011
    Publication date: June 27, 2013
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Chie Shishido, Maki Tanaka, Katsuhiro Sasada
  • Patent number: 8362426
    Abstract: The SEM has a dynamic range reference value setting unit for setting dynamic range reference values, a dynamic range adjustment unit for receiving an observation image signal delivered out of a secondary electron detector, adjusting the dynamic range of the observation image signal on the basis of the dynamic range reference values and outputting the thus adjusted observation image signal as an observation image signal after adjustment, a display image generation unit for determining luminous intensity levels of individual pixels of an image to be displayed based on the observation image signal after adjustment to generate a display image, a histogram generation unit for generating a histogram of luminous intensity levels of the display image and extracting, as a luminous intensity peak value, at which the frequency of luminous intensity is maximized, and a display unit for displaying the generated histogram and the extracted luminous intensity peak value.
    Type: Grant
    Filed: September 14, 2006
    Date of Patent: January 29, 2013
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Atsushi Kobaru, Katsuhiro Sasada, Hiroki Kawada
  • Patent number: 8203504
    Abstract: An image forming method and a charged particle beam apparatus suitable for suppressing the inclination of charging when scanning a two-dimensional area with a charged particle beam. A third scanning line located between a first scanning line and a second scanning line is scanned. After the first, second and third scanning lines have been scanned, a plurality of scanning lines are scanned between the first and third scanning lines and between the second and third scanning lines.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: June 19, 2012
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Atsushi Kobaru, Hidetoshi Morokuma, Hiroki Kawada, Sho Takami, Katsuhiro Sasada, Kouichi Yamamoto, Norio Satou, Kunio Nakanishi
  • Patent number: 8188427
    Abstract: A method and apparatus for alignment and astigmatism correction for a scanning electron microscope can prevent an alignment or correction error attributable to the conditions of a particular specimen. First, a difference is determined between optimal values acquired from an automatic axis alignment result on a standard sample, and those obtained from each of a plurality automatic axis alignment results on a observation target sample. An optimal value is then adjusted using the standard sample, by use of the difference thus obtained. Correspondingly, an optimal stigmator value (astigmatism correction signal) is acquired by using the standard sample, and storing the optimal stigmator value as a default value. The optimal stigmator value and the default value depending on the height of an observation target sample pattern are added, and an astigmatism correction is performed on the basis of the resultant stigmator value.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: May 29, 2012
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Junichi Kakuta, Kazuhiro Ueda, Tatsuya Maeda, Hiroyuki Saito, Katsuhiro Sasada
  • Patent number: 8178836
    Abstract: A method and a device are disclosed for suppressing error in electrostatic charge amount or defocus on the basis of electrostatic charge storage due to electron beam scanning when measuring the electrostatic charge amount of the sample or a focus adjustment amount by scanning the electron beam. An electrostatic charge measurement method, a focus adjustment method, or a scanning electron microscope for measuring an electrostatic charge amount or controlling an application voltage to the sample changes the application voltage to the energy filter while moving the scanning location of the electron beam on the sample.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: May 15, 2012
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Tatsuaki Ishijima, Katsuhiro Sasada, Ritsuo Fukaya
  • Patent number: 8071961
    Abstract: A sample measuring method and a charged particle beam apparatus are provided which remove contaminants, that have adhered to a sample in a sample chamber of an electron microscope, to eliminate adverse effects on the subsequent manufacturing processes. To achieve this objective, after the sample measurement or inspection is made by using a charged particle beam, contaminants on the sample are removed before the next semiconductor manufacturing process. This allows the contaminants adhering to the sample in the sample chamber to be removed and therefore failures or defects that may occur in a semiconductor fabrication process following the measurement and inspection can be minimized.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: December 6, 2011
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hiroaki Mito, Katsuhiro Sasada, Kazuo Kato, Tomohiro Kudo, Tomonori Saeki
  • Publication number: 20110032176
    Abstract: An image forming method and a charged particle beam apparatus suitable for suppressing the inclination of charging when scanning a two-dimensional area with a charged particle beam. A third scanning line located between a first scanning line and a second scanning line is scanned. After the first, second and third scanning lines have been scanned, a plurality of scanning lines are scanned between the first and third scanning lines and between the second and third scanning lines.
    Type: Application
    Filed: October 19, 2010
    Publication date: February 10, 2011
    Inventors: Atsushi KOBARU, Hidetoshi Morokuma, Hiroki Kawada, Sho Takami, Katsuhiro Sasada, Kouichi Yamamoto, Norio Satou, Kunio Nakanishi
  • Patent number: 7817105
    Abstract: An image forming method and a charged particle beam apparatus suitable for suppressing the inclination of charging when scanning a two-dimensional area with a charged particle beam. A third scanning line located between a first scanning line and a second scanning line is scanned. After the first, second and third scanning lines have been scanned, a plurality of scanning lines are scanned between the first and third scanning lines and between the second and third scanning lines.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: October 19, 2010
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Atsushi Kobaru, Hidetoshi Morokuma, Hiroki Kawada, Sho Takami, Katsuhiro Sasada, Kouichi Yamamoto, Norio Satou, Kunio Nakanishi
  • Publication number: 20100258739
    Abstract: A sample measuring method and a charged particle beam apparatus are provided which remove contaminants, that have adhered to a sample in a sample chamber of an electron microscope, to eliminate adverse effects on the subsequent manufacturing processes. To achieve this objective, after the sample measurement or inspection is made by using a charged particle beam, contaminants on the sample are removed before the next semiconductor manufacturing process. This allows the contaminants adhering to the sample in the sample chamber to be removed and therefore failures or defects that may occur in a semiconductor fabrication process following the measurement and inspection can be minimized.
    Type: Application
    Filed: May 23, 2007
    Publication date: October 14, 2010
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Hiroaki Mito, Katsuhiro Sasada, Kazuo Kato, Tomohiro Kudo, Tomonori Saeki
  • Publication number: 20100237241
    Abstract: A method and a device are disclosed for suppressing error in electrostatic charge amount or defocus on the basis of electrostatic charge storage due to electron beam scanning when measuring the electrostatic charge amount of the sample or a focus adjustment amount by scanning the electron beam. An electrostatic charge measurement method, a focus adjustment method, or a scanning electron microscope for measuring an electrostatic charge amount or controlling an application voltage to the sample changes the application voltage to the energy filter while moving the scanning location of the electron beam on the sample.
    Type: Application
    Filed: June 3, 2010
    Publication date: September 23, 2010
    Applicant: Hitachi High-Technologies Corporation
    Inventors: Tatsuaki ISHIJIMA, Katsuhiro Sasada, Ritsuo Fukaya
  • Patent number: 7745782
    Abstract: A method and a device are disclosed for suppressing error in electrostatic charge amount or defocus on the basis of electrostatic charge storage due to electron beam scanning when measuring the electrostatic charge amount of the sample or a focus adjustment amount by scanning the electron beam. An electrostatic charge measurement method, a focus adjustment method, or a scanning electron microscope for measuring an electrostatic charge amount or controlling an application voltage to the sample changes the application voltage to the energy filter while moving the scanning location of the electron beam on the sample.
    Type: Grant
    Filed: February 27, 2008
    Date of Patent: June 29, 2010
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Tatsuaki Ishijima, Katsuhiro Sasada, Ritsuo Fukaya
  • Patent number: 7626166
    Abstract: An object of the present invention is to prevent foreign bodies attracted by a magnetic field of an objective lens or an electric field of an electrode plate and adhered to a surface of the objective lens or electrode plate from dropping onto the surface of a sample and adhering there during observation of the sample. To achieve the above object, an electron microscope in which, when a sample to be measured is moved away from below an objective lens, an exciting current to the objective lens of a scanning electron microscope is turned off or excitation thereof is made weaker than before the sample to be measured being moved away, or an applied voltage to an acceleration cylinder for accelerating an electron beam is turned off or made lower than before the sample to be measured being moved away is proposed.
    Type: Grant
    Filed: February 27, 2008
    Date of Patent: December 1, 2009
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hiroyuki Saito, Katsuhiro Sasada
  • Patent number: 7601974
    Abstract: An object of this invention is to provide a charged particle beam apparatus that is capable of handling samples without adhering impurities onto the samples. In a scanning electron microscope in which a lubricant was coated on a sliding portion of a movable member that moves inside a vacuum chamber, a substance from which low molecular components were removed is used as the lubricant. It is thus possible to inhibit sample contamination and suppress the occurrence of defects in a process following measurement of the samples.
    Type: Grant
    Filed: April 17, 2007
    Date of Patent: October 13, 2009
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hiroaki Mito, Katsuhiro Sasada, Kazuo Kato, Tomohiro Kudo, Tomonori Saeki, Yasuo Yahagi, Masayuki Kobayashi
  • Patent number: 7566892
    Abstract: A structure of an electron beam apparatus having shielding properties for shielding against an environmental magnetic field is provided. The electron beam apparatus comprises a mirror barrel for housing a magnetic lens for converging an electron beam onto a specimen and a specimen chamber for housing the specimen, wherein a non-magnetic material having conductivity is used as a material for at least one of the mirror barrel and a main body of the specimen chamber. The material for the mirror barrel or the main body of the specimen chamber is an aluminum alloy and a thickness of a sidewall of the mirror barrel or the main body of the specimen chamber is 10 mm or more. A magnetic plate having a thickness smaller than that of the sidewall of the mirror barrel or the main body of the specimen chamber is provided on an inner sidewall of the mirror barrel or the main body of the specimen chamber.
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: July 28, 2009
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Tsuyoshi Inanobe, Sho Takami, Yoichi Ose, Katsuhiro Sasada