# US 10,770,266 B2 · Charged particle beam device and capturing condition adjusting method in charged particle beam device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,770,266 B2 - Document ID: US10770266B2 - Status: Granted - Kind: B2 - Application number: 16/436,297 - Filed: 2019-06-10 - Published: 2020-01-30 - Granted: 2020-09-08 - Earliest claimed: 2018-07-26 - Assignees: Hitachi High-Tech Corporation - Applicants: Hitachi High-Tech Corporation - Inventors: Tomohito Nakano; Toshiyuki Yokosuka; Yuko Sasaki; Minoru Yamazaki; Yuzuru Mochizuki - Web page: https://patentgrep.com/patent/US10770266B2 ## CPC - H01J 37/28: with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} - G01N 23/225: using electron or ion - H01J 37/141: Electromagnetic lenses - H01J 37/1478: {Beam tilting means, i.e. for stereoscopy or for beam channelling} - H01J 37/153: Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators - H01J 37/21: Means for adjusting the focus - H01J 2237/14: magnetic - H01J 2237/1504: Associated circuits - H01J 2237/1534: Aberrations - H01J 2237/1536: Image distortions due to scanning - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract A charged particle beam device includes an electron source which generates an electron beam, an objective lens which is applied with a coil current to converge the electron beam on a sample, a control unit which controls the current to be applied to the objective lens, a hysteresis characteristic storage unit which stores hysteresis characteristic information of the objective lens, a history information storage unit which stores history information related to the coil current, and an estimation unit which estimates a magnetic field generated by the objective lens on the basis of the coil current, the history information, and the hysteresis characteristic information. ## Claims ### Claim 1 A charged particle beam device, comprising: an electron source which generates an electron beam; an objective lens which is applied with a coil current to converge the electron beam on a sample; a control unit which controls the coil current to be applied to the objective lens; a hysteresis characteristic storage unit which stores hysteresis characteristic information of the objective lens; a history information storage unit which stores history information related to the coil current; and an estimation unit which estimates a magnetic field generated by the objective lens on the basis of the coil current, the history information, and the hysteresis characteristic information. ### Claim 2 (depends on 1) The charged particle beam device according to claim 1, wherein the history information includes information related to a value of a current at a time when the coil current is switched between increasing and decreasing. ### Claim 3 (depends on 1) The charged particle beam device according to claim 1, wherein the hysteresis characteristic information includes first curve information indicating a relation between the coil current and a magnetic flux density in a case where the coil current is increased from a first current to a second current after a lens reset process and decreased to the first current again, and second curve information indicating a relation between the coil current and the magnetic flux density in a case where the coil current is switched between increasing and decreasing before the coil current reaches the first current or the second current after the lens reset process. ### Claim 4 (depends on 3) The charged particle beam device according to claim 3, wherein the second curve information is expressed with a straight line. ### Claim 5 (depends on 1) The charged particle beam device according to claim 1, wherein the hysteresis characteristic information includes a play model which is expressed by a linear sum of a play hysteron. ### Claim 6 (depends on 1) The charged particle beam device according to claim 1, further comprising: a focusing lens which converges the electron beam; and a focusing lens current correction unit which corrects a coil current of the focusing lens according to the magnetic field estimated by the estimation unit. ### Claim 7 (depends on 1) The charged particle beam device according to claim 1, further comprising: a scanning unit which scans the electron beam; and a scanning region correction unit which corrects a region scanned by the scanning unit according to the magnetic field estimated by the estimation unit. ### Claim 8 (depends on 1) The charged particle beam device according to claim 1, further comprising: a magnification correction unit which corrects a deflection magnification of a captured image according to the magnetic field estimated by the estimation unit. ### Claim 9 (depends on 1) The charged particle beam device according to claim 1, further comprising: a rotation correction unit which corrects an image rotation of a captured image according to the magnetic field estimated by the estimation unit. ### Claim 10 A capturing condition adjusting method in a charged particle beam device which includes an electron source to generate an electron beam and an objective lens applied with a coil current to converge the electron beam on a sample, the method comprising: acquiring hysteresis characteristic information of the objective lens; performing a lens reset operation on the objective lens; determining the coil current; acquiring history information related to the coil current; and estimating a magnetic field generated by the objective lens on the basis of the coil current, the history information, and the hysteresis characteristic information. ### Claim 11 (depends on 10) The method according to claim 10, further comprising: correcting a deflection magnification of a captured image according to the estimated magnetic field. ### Claim 12 (depends on 10) The method according to claim 10, further comprising: correcting an image rotation of a captured image according to the estimated magnetic field.