Patents by Inventor Zhaohui Cheng

Zhaohui Cheng 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: 11223486
    Abstract: A digital signature method, a device, and a system of the present invention can generate a partial signature private key T corresponding to a user by a key generation center using a digital signature algorithm based on the EC-Schnorr, and sign a message M by using a standard digital signature algorithm such as the ECDSA. In the calculation of generating the second part w of the partial signature private key T, a signature assignment R is used, and the signature assignment R is a hash digest of a message including at least a pre-signature ? and an ID of a signature side. When signing the message M and verifying the signature of the message M, the operation requiring M as input uses a concatenation of R and M as input. The present invention uses a mechanism to connect two signature algorithms to ensure that the constructed complete algorithm can effectively resist known attacks.
    Type: Grant
    Filed: December 18, 2017
    Date of Patent: January 11, 2022
    Assignee: SHENZHEN OLYM INFORMATION SECURITY TECHNOLOGY CO., LTD.
    Inventors: Zhaohui Cheng, Feng Du
  • Publication number: 20210152370
    Abstract: A digital signature method, a device, and a system of the present invention can generate a partial signature private key T corresponding to a user by a key generation center using a digital signature algorithm based on the EC-Schnorr, and sign a message M by using a standard digital signature algorithm such as the ECDSA. In the calculation of generating the second part w of the partial signature private key T, a signature assignment R is used, and the signature assignment R is a hash digest of a message including at least a pre-signature ? and an ID of a signature side. When signing the message M and verifying the signature of the message M, the operation requiring M as input uses a concatenation of R and M as input. The present invention uses a mechanism to connect two signature algorithms to ensure that the constructed complete algorithm can effectively resist known attacks.
    Type: Application
    Filed: December 18, 2017
    Publication date: May 20, 2021
    Inventors: Zhaohui CHENG, Feng DU
  • Patent number: 10840060
    Abstract: A scanning electron microscope of the present invention performs scanning by changing a scanning line density in accordance with a sample when an image of a scanned region is formed by scanning a two-dimensional region on the sample with an electron beam or is provided with a GUI having sample information input means which inputs information relating to the sample and display means which displays a recommended scanning condition according to the input and performs scanning with a scanning line density according to the sample by selecting the recommended scanning condition. As a result, in observation using a scanning electron microscope, a suitable scanning device which can improve contrast of a profile of a two-dimensional pattern and suppress shading by suppressing the influence of charging caused by primary charged particle radiation and by improving a detection rate of secondary electrons and a scanning method are provided.
    Type: Grant
    Filed: May 18, 2018
    Date of Patent: November 17, 2020
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Zhaohui Cheng, Hikaru Koyama, Yoshinobu Kimura, Hiroyuki Shinada, Osamu Komuro
  • Patent number: 10727024
    Abstract: A charged particle beam device using a multi-pole type aberration corrector includes: a charged particle source which generates a primary charged particle beam; an aberration correction optical system which corrects aberrations of the primary charged particle beam; a detection unit which detects a secondary charged particle generated from a sample irradiated with the primary charged particle beam whose aberrations have been corrected; an image forming unit which forms a charged particle image of the sample from a signal obtained by detecting the secondary charged particle; an aberration correction amount calculation unit which processes the charged particle image, separates aberrations having different symmetries, selects an aberration to be preferentially corrected from the separated aberrations, and calculates a correction amount of the aberration correction optical system; and an aberration correction optical system control unit which controls the aberration correction optical system based on the calculate
    Type: Grant
    Filed: August 23, 2016
    Date of Patent: July 28, 2020
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Kotoko Urano, Zhaohui Cheng, Takeyoshi Ohashi, Hideyuki Kazumi
  • Patent number: 10446361
    Abstract: In order to provide an aberration correction system that realizes a charged particle beam of which the anisotropy is reduced or eliminated on a sample surface even in the case where there is magnetic interference between pole stages of an aberration corrector, an correction system includes a line cross position control device (209) which controls a line cross position in the aberration corrector of the charged particle beam so that a designed value and an actually measured value of the line cross position are equal to each other, an image shift amount extraction device (210), and a feedback determination device (211) which determines whether or not changing an excitation amount of the aberration corrector is necessary whether or not changing an excitation amount is necessary from an extracted image shift amount.
    Type: Grant
    Filed: July 1, 2015
    Date of Patent: October 15, 2019
    Assignee: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Zhaohui Cheng, Tomonori Nakano, Kotoko Urano, Takeyoshi Ohashi, Yasunari Sohda, Hideyuki Kazumi
  • Publication number: 20190214222
    Abstract: A charged particle beam device using a multi-pole type aberration corrector includes: a charged particle source which generates a primary charged particle beam; an aberration correction optical system which corrects aberrations of the primary charged particle beam; a detection unit which detects a secondary charged particle generated from a sample irradiated with the primary charged particle beam whose aberrations have been corrected; an image forming unit which forms a charged particle image of the sample from a signal obtained by detecting the secondary charged particle; an aberration correction amount calculation unit which processes the charged particle image, separates aberrations having different symmetries, selects an aberration to be preferentially corrected from the separated aberrations, and calculates a correction amount of the aberration correction optical system; and an aberration correction optical system control unit which controls the aberration correction optical system based on the calculate
    Type: Application
    Filed: August 23, 2016
    Publication date: July 11, 2019
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Kotoko URANO, Zhaohui CHENG, Takeyoshi OHASHI, Hideyuki KAZUMI
  • Publication number: 20180269032
    Abstract: A scanning electron microscope of the present invention performs scanning by changing a scanning line density in accordance with a sample when an image of a scanned region is formed by scanning a two-dimensional region on the sample with an electron beam or is provided with a GUI having sample information input means which inputs information relating to the sample and display means which displays a recommended scanning condition according to the input and performs scanning with a scanning line density according to the sample by selecting the recommended scanning condition. As a result, in observation using a scanning electron microscope, a suitable scanning device which can improve contrast of a profile of a two-dimensional pattern and suppress shading by suppressing the influence of charging caused by primary charged particle radiation and by improving a detection rate of secondary electrons and a scanning method are provided.
    Type: Application
    Filed: May 18, 2018
    Publication date: September 20, 2018
    Inventors: Zhaohui CHENG, Hikaru KOYAMA, Yoshinobu KIMURA, Hiroyuki SHINADA, Osamu KOMURO
  • Publication number: 20180190469
    Abstract: In order to provide an aberration correction system that realizes a charged particle beam of which the anisotropy is reduced or eliminated on a sample surface even in the case where there is magnetic interference between pole stages of an aberration corrector, an correction system includes a line cross position control device (209) which controls a line cross position in the aberration corrector of the charged particle beam so that a designed value and an actually measured value of the line cross position are equal to each other, an image shift amount extraction device (210), and a feedback determination device (211) which determines whether or not changing an excitation amount of the aberration corrector is necessary whether or not changing an excitation amount is necessary from an extracted image shift amount.
    Type: Application
    Filed: July 1, 2015
    Publication date: July 5, 2018
    Inventors: Zhaohui CHENG, Tomonori NAKANO, Kotoko URANO, Takeyoshi OHASHI, Yasunari SOHDA, Hideyuki KAZUMI
  • Patent number: 9991092
    Abstract: A scanning electron microscope of the present invention performs scanning by changing a scanning line density in accordance with a sample when an image of a scanned region is formed by scanning a two-dimensional region on the sample with an electron beam or is provided with a GUI having sample information input means which inputs information relating to the sample and display means which displays a recommended scanning conditioHn according to the input and performs scanning with a scanning line density according to the sample by selecting the recommended scanning condition. As a result, in observation using a scanning electron microscope, a suitable scanning device which can improve contrast of a profile of a two-dimensional pattern and suppress shading by suppressing the influence of charging caused by primary charged particle radiation and by improving a detection rate of secondary electrons and a scanning method are provided.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: June 5, 2018
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Zhaohui Cheng, Hikaru Koyama, Yoshinobu Kimura, Hiroyuki Shinada, Osamu Komuro
  • Patent number: 9830524
    Abstract: In the present invention, at the time of measuring, using a CD-SEM, a length of a resist that shrinks when irradiated with an electron beam, in order to highly accurately estimate a shape and dimensions of the resist before shrink, a shrink database with respect to various patterns is previously prepared, said shrink database containing cross-sectional shape data obtained prior to electron beam irradiation, a cross-sectional shape data group and a CD-SEM image data group, which are obtained under various electron beam irradiation conditions, and models based on such data and data groups, and a CD-SEM image of a resist pattern to be measured is obtained (S102), then, the CD-SEM image and data in the shrink database are compared with each other (S103), and the shape and dimensions of the pattern before the shrink are estimated and outputted (S104).
    Type: Grant
    Filed: May 24, 2012
    Date of Patent: November 28, 2017
    Assignee: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Tomoko Sekiguchi, Takeyoshi Ohashi, Junichi Tanaka, Zhaohui Cheng, Ruriko Tsuneta, Hiroki Kawada, Seiko Hitomi
  • Patent number: 9287084
    Abstract: Provided are an aberration corrector that reduces irregularity of a magnetic field of a multipole to obtain an image of high resolution and a charged particle beam apparatus using the same. The aberration corrector includes a plurality of magnetic field type poles, a ring that magnetically connects the plurality of poles with one another and an adjustment member disposed between the pole and the ring to adjust a spacing between the pole and the ring per pole.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: March 15, 2016
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Zhaohui Cheng, Hideo Kashima, Hiroaki Baba, Takeyoshi Ohashi, Tomonori Nakano, Kotoko Urano, Naomasa Suzuki
  • Patent number: 9202665
    Abstract: Provided is a charged particle beam apparatus adapted so that even when an additional device is not mounted in the charged particle beam apparatus, the apparatus rapidly removes, by neutralizing, a local charge developed on a region of a sample that has been irradiated with a charged particle beam. After charged particle beam irradiation for measurement of the sample, the apparatus controls a retarding voltage or/and an accelerating voltage at a stage previous to a next measurement, and then neutralizes an electric charge by reducing a difference between a value of the retarding voltage and that of the accelerating voltage to a value smaller than during the currently ongoing measurement. The charged particle beam achieves neutralizing without reducing throughput, since the local charge developed on the region of the sample that has been irradiated with the charged particle beam is removed, even without an additional device mounted in the apparatus.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: December 1, 2015
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Hiroyuki Matsui, Osamu Komuro, Makoto Nishihara, Zhaohui Cheng
  • Publication number: 20150248944
    Abstract: Provided are an aberration corrector that reduces irregularity of a magnetic field of a multipole to obtain an image of high resolution and a charged particle beam apparatus using the same. The aberration corrector includes a plurality of magnetic field type poles, a ring that magnetically connects the plurality of poles with one another and an adjustment member disposed between the pole and the ring to adjust a spacing between the pole and the ring per pole.
    Type: Application
    Filed: January 28, 2015
    Publication date: September 3, 2015
    Inventors: Zhaohui Cheng, Hideo Kashima, Hiroaki Baba, Takeyoshi Ohashi, Tomonori Nakano, Kotoko Urano, Naomasa Suzuki
  • Publication number: 20150036914
    Abstract: In the present invention, at the time of measuring, using a CD-SEM, a length of a resist that shrinks when irradiated with an electron beam, in order to highly accurately estimate a shape and dimensions of the resist before shrink, a shrink database with respect to various patterns is previously prepared, said shrink database containing cross-sectional shape data obtained prior to electron beam irradiation, a cross-sectional shape data group and a CD-SEM image data group, which are obtained under various electron beam irradiation conditions, and models based on such data and data groups, and a CD-SEM image of a resist pattern to be measured is obtained (S102), then, the CD-SEM image and data in the shrink database are compared with each other (S103), and the shape and dimensions of the pattern before the shrink are estimated and outputted (S104).
    Type: Application
    Filed: May 24, 2012
    Publication date: February 5, 2015
    Inventors: Tomoko Sekiguchi, Takeyoshi Ohashi, Junichi Tanaka, Zhaohui Cheng, Ruriko Tsuneta, Hiroki Kawada, Seiko Hitomi
  • Publication number: 20140027635
    Abstract: Provided is a charged particle beam apparatus adapted so that even when an additional device is not mounted in the charged particle beam apparatus, the apparatus rapidly removes, by neutralizing, a local charge developed on a region of a sample that has been irradiated with a charged particle beam. After charged particle beam irradiation for measurement of the sample, the apparatus controls a retarding voltage or/and an accelerating voltage at a stage previous to a next measurement, and then neutralizes an electric charge by reducing a difference between a value of the retarding voltage and that of the accelerating voltage to a value smaller than during the currently ongoing measurement. The charged particle beam achieves neutralizing without reducing throughput, since the local charge developed on the region of the sample that has been irradiated with the charged particle beam is removed, even without an additional device mounted in the apparatus.
    Type: Application
    Filed: November 30, 2011
    Publication date: January 30, 2014
    Inventors: Hiroyuki Matsui, Osamu Komuro, Makoto Nishihara, Zhaohui Cheng
  • Patent number: 8309923
    Abstract: Provided is a sample observing method wherein the effect on throughput is minimized, and a pattern profile can be obtained at high accuracy even in a complicated LSI pattern, regardless of the scanning direction of an electron beam. In the sample observing method, the presence or absence of an edge parallel to a scanning direction (707) of an electron beam is judged regarding an edge (708) of a pattern to be observed (S702); if the edge is present, an area in the vicinity of the pattern edge is designated as a local pre-dose area (709) (S703); a local pre-dose of an electron beam is performed, so that the initial charged state is controlled not to return secondary electrons generated by irradiation of an electron beam when an image is captured, to the surface of a sample.
    Type: Grant
    Filed: February 9, 2010
    Date of Patent: November 13, 2012
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Seiko Omori, Zhaohui Cheng, Hideyuki Kazumi
  • Patent number: 8207513
    Abstract: A charged particle beam apparatus is provided which has high resolving power and a wide scanning region (observation field of view). The apparatus has a unit for adjusting the focus, a unit for adjusting astigmatism, a unit for controlling and detecting scanning positions and a controller operative to control the focus adjustment and astigmatism adjustment at a time in interlocked relation to the scanning positions, thereby assuring compatibility between the high resolving power and the observation view field of a wide area.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: June 26, 2012
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Yuko Sasaki, Yasuhiro Gunji, Zhaohui Cheng
  • Publication number: 20120153145
    Abstract: A scanning electron microscope of the present invention performs scanning by changing a scanning line density in accordance with a sample when an image of a scanned region is formed by scanning a two-dimensional region on the sample with an electron beam or is provided with a GUI having sample information input means which inputs information relating to the sample and display means which displays a recommended scanning condition according to the input and performs scanning with a scanning line density according to the sample by selecting the recommended scanning condition. As a result, in observation using a scanning electron microscope, a suitable scanning device which can improve contrast of a profile of a two-dimensional pattern and suppress shading by suppressing the influence of charging caused by primary charged particle radiation and by improving a detection rate of secondary electrons and a scanning method are provided.
    Type: Application
    Filed: July 30, 2010
    Publication date: June 21, 2012
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Zhaohui Cheng, Hikaru Koyama, Yoshinobu Kimura, Hiroyuki Shinada, Osamu Komuro
  • Publication number: 20110303843
    Abstract: Provided is a sample observing method wherein the effect on throughput is minimized, and a pattern profile can be obtained at high accuracy even in a complicated LSI pattern, regardless of the scanning direction of an electron beam. In the sample observing method, the presence or absence of an edge parallel to a scanning direction (707) of an electron beam is judged regarding an edge (708) of a pattern to be observed (S702); if the edge is present, an area in the vicinity of the pattern edge is designated as a local pre-dose area (709) (S703); a local pre-dose of an electron beam is performed, so that the initial charged state is controlled not to return secondary electrons generated by irradiation of an electron beam when an image is captured, to the surface of a sample.
    Type: Application
    Filed: February 9, 2010
    Publication date: December 15, 2011
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Seiko Omori, Zhaohui Cheng, Hideyuki Kazumi
  • Patent number: 7928384
    Abstract: A charged particle beam device including a function for measuring localized static charges on a sample. A primary charged particle beam scans a sample positioned in a mirror state to acquire an image. The acquired image may be an image of the sample or may be an image of a structural component in the charged particle optical system. The acquired image is compared with a standard sample image and the localized static charge is measured.
    Type: Grant
    Filed: August 12, 2008
    Date of Patent: April 19, 2011
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Zhaohui Cheng, Tasuku Yano, Seiko Omori