Method of Suppressing Beam Position Drift, Method of Suppressing Beam Dimension Drift, and Charged-Particle Beam Lithography System

摘要

A lithography method and system have means for determining a convergence value d_c from a relation of beam current to beam position drift (or beam dimension drift) produced in the past; means for finding a beam current i(t) as a function of the convergence value d_c of beam position drift (or beam dimension drift), a measured value d_m of beam position drift (or beam dimension drift), a gain constant g, and a convergence value c of beam position drift(or beam dimension drift) per unit beam current and using an equation given by i(t)={(1+g)·d_cg·d_m(t)}/c; means for making a check regarding d_m and d_c as to whether d_m approaches d_c and, thus, a relationship given by |d_m−d_c|ε holds, where ε is a positive number providing a decision criterion under the condition where the gain constant g of the beam current i(t) satisfies a relationship given by g0.