Method and system for measuring the diameter of an electron beam

摘要

A method of measuring the diameter of an electron beam in which the electron beam diameter is measured from the leading edge or trailing edge of a detector signal that is obtained as the mark area formed on the specimen is scanned by the electron beam. This method comprises the following steps: scanning the specimen by the electron beam at least once to find the maximum and minimum values of the detector signal; setting two threshold levels based on the maximum and minimum values; scanning the mark area by the electron beam to measure the time interval during which the level of the detector signal is within the two threshold levels; and calculating the beam diameter.