Patent ID: 6982138
Filing Date: 2006-01-03
Classification: G03F

Abstract:
1. A method of making a conclusion about a presence or absence of photoresist in openings of a photoresist mask, comprising the steps of obtaining in a scanning electron microscope a video signal of a bottom of an opening of a photoresist mask; and comparing values of the video signal in different points of an image which contains the opening, wherein said comparing includes selecting a portion of a field of vision outside of an image of the opening; determining a mean value of the video signal and a mean square amplitude of noise on the selected portion; subdividing the image of the bottom of the opening into fragments; repeating calculations of a mean signal in each fragment; calculating paired differences of average values of the signal; selecting those paired differences which exceed a threshold; and making a conclusion about a presence or absence of non-removed photoresist with determination of borders of the islands.