Substrate inspecting system using electron beam and substrate inspecting method using electron beam

A host computer controlling a secondary optical system under such an image focusing condition that secondary beams obtained from an arbitrary region on a substrate form an image on a MCP detector, in accordance with a correlation between a state of the substrate and an energy of the secondary electrons and the reflected electrons upon the secondary optical system, in which the energy of the secondary electron beams is various depending on the state of the substrate. The host computer also measures quantitatively a physical and/or chemical characteristic of the substrate on a basis of the image focusing condition and the image signals.