Method for determining maximum altitude of particles on substrate, involves localizing highest point by accommodating substrate with object i.e. particles, in different directions, and determining altitude of highest point

摘要

The method involves localizing a highest point by accommodating a substrate with an object (3) i.e. particles, in different directions, and determining altitude of the highest point. A direction-sensitive image is produced by subtraction of two recorded images. Altitude profiles in different directions are computed for the localization of the highest point, and the point is determined by addition of the profiles, where the directions run orthogonal to each other. A position of a focus level is varied by shifting cross-over points from electron beams (1) of a scanning electron microscope.