METHOD AND DEVICE FOR DETECTING STEPPED PATTERN

摘要

PURPOSE:To stably detect the position of a stepped pattern formed on a sample or its geometric information with high accuracy. CONSTITUTION:An interference pattern 53 obtained when an alignment pattern 48 is irradiated with light 41 has a large signal change, because the influence of the interference between reflected light 50 mainly from the boundary 47 between a stepped pattern and photoresist 46 and reflected light 52 from a semitransparent mirror 51 is the strongest and the phase changes by the height (e) of a step at the stepped part of the pattern 48. Therefore, the center position of the pattern 48 can be found with high accuracy from the changes of photoelectrically converted signals against the pattern 53.