Patent ID: 6574359
Filing Date: 2003-06-03
Classification: G01N,G06T

Abstract:
A method of inspecting a feature on a film surface, comprising:illuminating the feature with laser radiation; detecting radiation scattered from the feature with a plurality of detectors, each of the plurality of detectors having a known position; computing a position of the feature observed by each of the plurality detectors based upon the radiation scattered from the feature; computing an average position of the positions observed by each of the plurality of detectors; computing a first value for each of the plurality of detectors, the first value being the scalar product of the known position of a given detector with the difference of the position of the feature observed by that given detector and the average of the positions observed by each of the plurality of detectors; and computing a second value indicative of the topography of the feature by summing first values for the plurality of detectors.