METHOD FOR EVALUATING EXPOSURE PATTFRN, MARK FOR EVALUATING EXPOSURE PATTERN, AND DEVICE FOR EVALUATING EXPOSURE PATTERN

摘要

PROBLEM TO BE SOLVED: To obtain a highly reliable exposure pattern evaluating method by which an exposure pattern can be evaluated without receiving any influence from layers already formed on a wafer by picking up the two-dimensional image of a transfer evaluation mark and finding the peak value of the cross-correlation function or normalized correlation function between the image of the transfer evaluation mark and the template of a designed evaluation mark pattern. ;SOLUTION: An evaluation mark 15 on a wafer 13 is irradiated with irradiating light passed through a condenser lens 5 and the reflected light of the irradiating light is led to a CCD camera 21 positioned above an image forming lens 19 so that the magnified image of the mark 15 may be formed in the camera 21 through an objective lens 11, a half mirror 7, and the lens 19 coaxially positioned above the mirror 7. Image signals are sent to an image processing section 23 and the section 23 takes the sums of image data in the length direction and vertical direction of the mark 15, calculates the cross-correlation function between the sums and the data obtained by adding design values of the mark and the peak values of the functions, and outputs the peak values to a peak value displaying section 31 for display. Therefore, an exposure pattern can be evaluated highly reliably without receiving any influence from each layer already formed on the water 13.;COPYRIGHT: (C)1998,JPO