Patents by Inventor Nobuhiro Okai

Nobuhiro Okai 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).

  • Publication number: 20250003898
    Abstract: A foreign object height measurement method including: storing in advance dependence data indicating a dependence of a calculated value of the height of the foreign object calculated from a foreign object image extracted from the charged particle image on an orientation of the foreign object; extracting a measurement target foreign object image, being an image of a measurement target foreign object, from the charged particle image; and outputting a measurement value of a height of the measurement target foreign object along with a warning regarding reliability or measuring the height of the measurement target foreign object from a charged particle image acquired by rotating the sample stage and changing an orientation of the measurement target foreign object detected from the measurement target foreign object image when it is determined that the orientation of the measurement target foreign object does not satisfy an acceptable error range based on the dependence data.
    Type: Application
    Filed: January 26, 2022
    Publication date: January 2, 2025
    Inventors: Wei SUN, Naomasa SUZUKI, Nobuhiro OKAI, Keiichiro HITOMI
  • Patent number: 11852599
    Abstract: Provided is an image processing system capable of estimating a three-dimensional shape of a semiconductor pattern or a particle by solving problems of measurement reduction in a height direction and taking an enormous amount of time at a time of acquiring learning data. The image processing system according to the disclosure stores a detectable range of a detector provided in a charged particle beam device in a storage device in advance, generates a simulated image of a three-dimensional shape pattern using the detectable range, and learns a relationship between the simulated image and the three-dimensional shape pattern in advance.
    Type: Grant
    Filed: July 22, 2021
    Date of Patent: December 26, 2023
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Nobuhiro Okai, Naomasa Suzuki, Muneyuki Fukuda
  • Publication number: 20230238212
    Abstract: Provided is an electron microscope for generating an observation image of a sample by using an electron beam in order to obtain a scanning electron microscope image by low angle backscattered electrons, which are backscattered electrons emitted at a low angle with respect to a sample surface, even for an electron microscope including an objective lens that leaks a magnetic field to a sample.
    Type: Application
    Filed: September 24, 2021
    Publication date: July 27, 2023
    Inventors: Hiroyasu SHICHI, Nobuhiro OKAI, Naomasa SUZUKI, Masanobu IEDA
  • Publication number: 20220042936
    Abstract: Provided is an image processing system capable of estimating a three-dimensional shape of a semiconductor pattern or a particle by solving problems of measurement reduction in a height direction and taking an enormous amount of time at a time of acquiring learning data. The image processing system according to the disclosure stores a detectable range of a detector provided in a charged particle beam device in a storage device in advance, generates a simulated image of a three-dimensional shape pattern using the detectable range, and learns a relationship between the simulated image and the three-dimensional shape pattern in advance.
    Type: Application
    Filed: July 22, 2021
    Publication date: February 10, 2022
    Inventors: Nobuhiro Okai, Naomasa Suzuki, Muneyuki Fukuda
  • Patent number: 11211224
    Abstract: To improve detection efficiency of secondary particles without increasing a size of a charged particle beam apparatus, a charged particle beam apparatus according to the invention includes: a charged particle beam source configured to irradiate a sample with a primary particle beam; a scanning deflector configured to scan and deflect the primary particle beam to a desired position of the sample; and a detector configured to detect secondary particles emitted from the desired position. The charged particle beam apparatus further includes: a focusing lens electrode arranged coaxially with the primary particle beam and configured to generate a focusing electric field that is an electric field that focuses a trajectory of the secondary particles; and a mesh electrode configured to reduce leakage of the focusing electric field on a trajectory of the primary particle beam.
    Type: Grant
    Filed: April 26, 2018
    Date of Patent: December 28, 2021
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Nobuhiro Okai, Daisuke Bizen, Tomoyasu Shojo, Naomasa Suzuki, Muneyuki Fukuda
  • Publication number: 20210249221
    Abstract: To improve detection efficiency of secondary particles without increasing a size of a charged particle beam apparatus, a charged particle beam apparatus according to the invention includes: a charged particle beam source configured to irradiate a sample with a primary particle beam; a scanning deflector configured to scan and deflect the primary particle beam to a desired position of the sample; and a detector configured to detect secondary particles emitted from the desired position. The charged particle beam apparatus further includes: a focusing lens electrode arranged coaxially with the primary particle beam and configured to generate a focusing electric field that is an electric field that focuses a trajectory of the secondary particles; and a mesh electrode configured to reduce leakage of the focusing electric field on a trajectory of the primary particle beam.
    Type: Application
    Filed: April 26, 2018
    Publication date: August 12, 2021
    Applicant: HITACHI HIGH-TECH CORPORATION
    Inventors: Nobuhiro OKAI, Daisuke BIZEN, Tomoyasu SHOJO, Naomasa SUZUKI, Muneyuki FUKUDA
  • Patent number: 10121632
    Abstract: Provided is a charged particle beam apparatus which includes a charged particle source, a sample table on which a sample is placed, a charged particle beam optical system that includes an objective lens and emits a charged particle beam emitted from the charged particle source onto the sample, a plurality of detectors which detect secondary particles emitted from the sample when being irradiated with the charged particle beam, and a rotation member which magnetically, electrically, or mechanically changes a detected azimuth angle of the secondary particles emitted from the sample.
    Type: Grant
    Filed: April 14, 2017
    Date of Patent: November 6, 2018
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Nobuhiro Okai, Natsuki Tsuno, Naomasa Suzuki, Tomoyasu Shojo
  • Publication number: 20170316915
    Abstract: Provided is a charged particle beam apparatus which includes a charged particle source, a sample table on which a sample is placed, a charged particle beam optical system that includes an objective lens and emits a charged particle beam emitted from the charged particle source onto the sample, a plurality of detectors which detect secondary particles emitted from the sample when being irradiated with the charged particle beam, and a rotation member which magnetically, electrically, or mechanically changes a detected azimuth angle of the secondary particles emitted from the sample.
    Type: Application
    Filed: April 14, 2017
    Publication date: November 2, 2017
    Inventors: Nobuhiro OKAI, Natsuki TSUNO, Naomasa SUZUKI, Tomoyasu SHOJO
  • Patent number: 9261360
    Abstract: Disclosed is a charged particle beam microscope which can obtain information about pattern materials and stereostructure without lowering throughput of pattern dimension measurement. To achieve this, the charged particle beam microscope acquires a plurality of frame images by scanning the field of view of the sample (S304, 305), adds the images together (S307), computes the dimensions of the pattern formed on the sample (308) and at the same time acquires pattern information (314) using components of a frame image, such as a single frame image or subframe image, as a separated image (309, 310).
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: February 16, 2016
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Nobuhiro Okai, Yasunari Sohda, Junichi Tanaka
  • Patent number: 8969801
    Abstract: To provide a scanning electron microscope that can detect reflected electrons of any emission angle, the scanning electron microscope, which obtains an image by detecting electrons from a sample (19) has: a control electrode (18) that discriminates between secondary electrons from the sample (19) and reflected electrons; a secondary electron conversion electrode (13) that generates secondary electrons by the impact of reflected electrons; a withdrawing electrode (12) that withdraws those secondary electrons; an energy filter (11) that discriminates between the secondary electrons withdrawn and electrons reflected from the sample (19); and a control calculation means (36) that selects a combination of voltages applied to the secondary electron conversion electrode (13), the withdrawing electrode (12), and energy filter (11).
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: March 3, 2015
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Nobuhiro Okai, Yasunari Sohda, Ritsuo Fukaya, Zhigang Wang
  • Patent number: 8907267
    Abstract: This charged particle beam device is characterized by controlling a deflector in a manner so as to correct the amount of scanning deflection of a charged particle beam between: a first detection condition for detecting a secondary charged particle (112) signal; and a second detection condition for detecting a reflected charged particle (111) signal. As a result, it is possible to correct length measurement error and scaling fluctuation arising when altering the type of charged particle to detect. Thus, in the observation, measurement, and the like of a low-step sample or a charged sample, even when forming an image that is on the basis of the reflected charged particle signal, it is possible to obtain an accurate image regardless of length measurement error and scaling fluctuation.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: December 9, 2014
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Zhigang Wang, Nobuhiro Okai, Hidetoshi Sato, Ritsuo Fukaya
  • Publication number: 20140299769
    Abstract: To provide a scanning electron microscope that can detect reflected electrons of any emission angle, the scanning electron microscope, which obtains an image by detecting electrons from a sample (19) has: a control electrode (18) that discriminates between secondary electrons from the sample (19) and reflected electrons; a secondary electron conversion electrode (13) that generates secondary electrons by the impact of reflected electrons; a withdrawing electrode (12) that withdraws those secondary electrons; an energy filter (11) that discriminates between the secondary electrons withdrawn and electrons reflected from the sample (19); and a control calculation means (36) that selects a combination of voltages applied to the secondary electron conversion electrode (13), the withdrawing electrode (12), and energy filter (11).
    Type: Application
    Filed: September 27, 2012
    Publication date: October 9, 2014
    Inventors: Nobuhiro Okai, Yasunari Sohda, Ritsuo Fukaya, Zhigang Wang
  • Publication number: 20140217274
    Abstract: This charged particle beam device is characterized by controlling a deflector in a manner so as to correct the amount of scanning deflection of a charged particle beam between: a first detection condition for detecting a secondary charged particle (112) signal; and a second detection condition for detecting a reflected charged particle (111) signal. As a result, it is possible to correct length measurement error and scaling fluctuation arising when altering the type of charged particle to detect. Thus, in the observation, measurement, and the like of a low-step sample or a charged sample, even when forming an image that is on the basis of the reflected charged particle signal, it is possible to obtain an accurate image regardless of length measurement error and scaling fluctuation.
    Type: Application
    Filed: August 16, 2012
    Publication date: August 7, 2014
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Zhigang Wang, Nobuhiro Okai, Hidetoshi Sato, Ritsuo Fukaya
  • Patent number: 8742342
    Abstract: A scanning electron microscope suppresses a beam drift by reducing charging on a sample surface while suppressing resolution degradation upon observation of an insulator sample. An electron microscope includes an electron source and an objective lens that focuses an electron beam emitted from the electron source, which provides an image using a secondary signal generated from the sample irradiated with the electron beam. A magnetic body with a continuous structure and an inside diameter larger than an inside diameter of an upper pole piece that forms the objective lens is provided between the objective lens and the sample.
    Type: Grant
    Filed: November 1, 2010
    Date of Patent: June 3, 2014
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Nobuhiro Okai, Yasunari Sohda
  • Patent number: 8692197
    Abstract: A scanning electron microscope and an optical-condition setting method are provided. The optical condition allows the suppression of a lowering in the measurement and inspection accuracy caused by the influence of electrification, even if there are a large number of measurement and inspection points. A pattern on a sample is measured based on the detection of electrons by scanning the sample surface with an electron beam. A change in measurement values relative to the number of measurements is determined from the measurement values at a plurality of measurement points on the sample, and the sample-surface electric field is controlled so that the inclination of the change becomes equal to zero, or becomes close to zero.
    Type: Grant
    Filed: February 9, 2011
    Date of Patent: April 8, 2014
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Zhigang Wang, Nobuhiro Okai, Ritsuo Fukaya
  • Patent number: 8487251
    Abstract: An object of the present invention is to provide a scanning electron microscope aiming at making it possible to control the quantity of electrons generated by collision of electrons emitted from a sample with other members, and a sample charging control method using the control of electron quantity. To achieve the object, a scanning electron microscope including a plurality of apertures through which an electron beam can pass and a mechanism for switching the apertures for the electron beam, and a method for controlling sample charging by switching the apertures are proposed. The plurality of apertures are at least two apertures. Portions respectively having different secondary electron emission efficiencies are provided on peripheral portions of the at least two apertures on a side opposed to the sample. The quantity of electrons generated by collision of electrons emitted from the sample can be controlled by switching the apertures.
    Type: Grant
    Filed: August 8, 2009
    Date of Patent: July 16, 2013
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Ritsuo Fukaya, Nobuhiro Okai, Koki Miyahara, Zhigang Wang
  • Publication number: 20120327213
    Abstract: Disclosed is a charged particle beam microscope which can obtain information about pattern materials and stereostructure without lowering throughput of pattern dimension measurement. To achieve this, the charged particle beam microscope acquires a plurality of frame images by scanning the field of view of the sample (S304, 305), adds the images together (S307), computes the dimensions of the pattern formed on the sample (308) and at the same time acquires pattern information (314) using components of a frame image, such as a single frame image or subframe image, as a separated image (309, 310).
    Type: Application
    Filed: February 22, 2011
    Publication date: December 27, 2012
    Applicant: Hitachi high-Technologies Corporation
    Inventors: Nobuhiro Okai, Yasunari Sohda, Junichi Tanaka
  • Publication number: 20120318977
    Abstract: It is an object of the present invention to provide an optical-condition setting method for a charged-particle beam device, and the charged-particle beam device which make it possible to set the following optical condition: Namely, an optical condition which allows the suppression of a lowering in the measurement and inspection accuracy caused by the influence of electrification, even if there exist a large number of measurement and inspection points.
    Type: Application
    Filed: February 9, 2011
    Publication date: December 20, 2012
    Applicant: Hitachi High-Technologies Corporation
    Inventors: Zhigang Wang, Nobuhiro Okai, Ritsuo Fukaya
  • Publication number: 20120217393
    Abstract: A scanning electron microscope suppresses a beam drift by reducing charging on a sample surface while suppressing resolution degradation upon observation of an insulator sample. An electron microscope includes an electron source and an objective lens that focuses an electron beam emitted from the electron source, which provides an image using a secondary signal generated from the sample irradiated with the electron beam. A magnetic body with a continuous structure and an inside diameter larger than an inside diameter of an upper pole piece that forms the objective lens is provided between the objective lens and the sample.
    Type: Application
    Filed: November 1, 2010
    Publication date: August 30, 2012
    Applicant: Hitachi High-Technologies Corporation
    Inventors: Nobuhiro Okai, Yasunari Sohda
  • Patent number: 8125518
    Abstract: Provided is a scanning electron microscope including: an image recording unit (112) which stores a plurality of acquired frame images; a correction analyzing handling unit (113) which calculates a drift amount between frame images and a drift amount between a plurality of field images constituting a frame image; and a data handling unit (111) which corrects positions of respective field images constituting the plurality of fields images according to the drift amount between the field images and superimposes the field images on one another so as to create a new frame image. This provides a scanning electron microscope which can obtain a clear frame image even if an image drift is caused during observation of a pattern on a semiconductor substrate or an insulating object.
    Type: Grant
    Filed: November 24, 2009
    Date of Patent: February 28, 2012
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Nobuhiro Okai, Yasunari Sohda