METHOD FOR APPROXIMATING EID FUNCTION IN CHARGED PARTICLE BEAM EXPOSURE APPARATUS, METHOD FOR CORRECTING APPROXIMATION EFFECT AND METHOD FOR DECIDING RETICLE PATTERN

摘要

PROBLEM TO BE SOLVED: To provide a method for setting the parameter of the approximation function of an EID function showing the planar distribution of energy stored in a resist.;SOLUTION: (1) A plurality (N) of approximation formulas of the EID function are set up (2) to obtain similarity between an exposure pattern obtained by calculation using the approximated EID function and an exposure pattern obtained by an exposure experiment. (3) A parameter for deciding the function about a plurality (P) of approximation formulas selected randomly from among the approximated EID functions except the T-number of the EID functions of high similarity or at least one optional value selected randomly from prescribed ones among coupling coefficients of the functions with each other is varied to generate the N-number of new approximated EID functions to replace the approximated functions with varied values. (4) Operations of the (2) to (3) are repeated until the similarity is converted. Thereafter, the approximation formula of the EID function of the highest similarity is adopted as an approximation formula.;COPYRIGHT: (C)2003,JPO