Method of suppressing beam position drift, method of suppressing beam dimension drift, and charged particle beam lithography system

Abstract

A lithography method and system have means for determining a convergence value dfrom 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 dof beam position drift (or beam dimension drift), a measured value dof 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−g·d(t)}/c; means for making a check regarding dand das to whether dapproaches dand, thus, a relationship given by |d−d|<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 g>0.