Electron beam drawing method

Claim 1

An electron beam drawing method whereby a surface of a semiconductor wafer is divided into a number of blocks, each block is divided into a plurality of chips, four matching marks are formed in each of the blocks, a correction is made to an electron beam deflecting system on the basis of position information of detected matching marks, and the blocks are then drawn, wherein the correction is performed on the basis of different correcting equations in correspondence to the number of said matching marks detected, and wherein when the number of said matching marks detected is three, six correction coefficients are determined by a method of least squares on the basis of the coordinates of said three matching marks detected and thereafter, the correction is executed by using the following correcting equations: ΔX=AX+BY+D Δ=A'X+B'Y+D' where, X and Y denote coordinates from the center of the block, ΔX and ΔY indicate correction amounts, and A, B, D, A', B' and D' represent correction coefficients and have the following meanings: A : gain term in the X direction, B : rotational term regarding a Y axis, D : shift term in the X direction, A': rotational term regarding an X axis, B': gain term in the Y direction, D': shift term in the Y direction.