| 摘要 |
PROBLEM TO BE SOLVED: To quickly converge beam position drift in a method for suppressing the beam position drift. SOLUTION: A charged particle beam plotting device includes: a means for determining the convergence value d<SB>c</SB>of beam position drift generated in plotting or device calibration from relation between past beam position drift and beam currents; a means for obtaining a beam current i(t) from i(t)=ä(1+g)×d<SB>c</SB>-g×d<SB>m</SB>(t)}/c as the function of the convergence value d<SB>c</SB>of the beam position drift, the measurement value d<SB>m</SB>of the beam position drift, gain constant g, and a beam position drift convergence value c per unit beam current; and a means for checking whether the d<SB>m</SB>approaches the d<SB>c</SB>and ¾d<SB>m</SB>-d<SB>c</SB>¾<εis formed or not when the gain constant g of the beam current i(t) is g>0 andεis a positive number to be a determination standard as regards d<SB>m</SB>and d<SB>c</SB>. When ¾d<SB>m</SB>-d<SB>c</SB>¾<εis formed, control is stopped and calibration or plotting is performed. COPYRIGHT: (C)2009,JPO&INPIT
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