Electron Beam Apparatus And Method of Operating The Same

An electron beam apparatus is offered which can well detect backscattered electrons or both backscattered electrons and secondary electrons if an electron detector is disposed above an objective lens in the apparatus. The electron beam apparatus has an electron beam source for emitting an electron beam accelerated by a given accelerating voltage, the objective lens for focusing the electron beam emitted from the beam source onto a specimen, scan coils for scanning the focused beam over the specimen, and the electron detector located above the objective lens and provided with a hole permitting passage of the beam. The detector has an electrode for producing an electric field that attracts the electrons produced from the specimen in response to the electron beam irradiation. Correction coils for correcting deflection of the beam caused by the electric field are located below the detector.