A method of measuring properties of a sample using an electron beam.
Coordinates of a measurement site on the sample, and a diameter of the
electron beam are defined. Multiple measurement locations are determined
within the measurement site, using the coordinates of the measurement
site and the diameter of the electron beam. The measurement locations are
selected such that the electron beam when directed at the multiple
measurement locations (either through beam deflection or sample movement)
substantially covers the measurement site. The electron beam is directed
to the measurement locations and properties of the sample are measured at
each of the measurement locations.