Patent ID: 7425704

Claim:
An inspection method using an electron beam, comprising the steps of: irradiating a sample on which a pattern is formed with an electron beam; generating an inspection image and a reference image based on a secondary electron or a reflected electron emitted by the sample; determining an abnormal pattern based on a difference in the halftone values of each pixel between the inspection image and reference image; determining a plurality of feature quantities of the abnormal pattern based on an image of the abnormal pattern, the plurality of feature quantities including the difference in the halftone values of each pixel between the inspection image and the reference image and a differentiated value of the halftone value of the abnormal pattern in the inspection image; arranging the plurality of feature quantities of the abnormal pattern on a distribution chart created from the feature quantities of the abnormal pattern, the distribution chart including axes to which the difference in the halftone values and the differentiated value of the halftone value are assigned; generating a plurality of groups of abnormal patterns in the distribution chart; displaying on a screen the inspection image, the reference image and an abnormal pattern extraction image of the abnormal pattern of one of the plurality of groups together with the distribution chart; and designating a range for classifying the type of the abnormal pattern based on the display on the screen in the step of displaying, wherein the feature quantities include the sum of halftone differences of each pixel determined on the basis of the inspection image and reference image of the abnormal pattern, and the sum of absolute values of the differentiated values of halftone values between each pairs of adjacent pixels determined on the basis of the inspection image including the abnormal pattern.