US Patent 7880143 Electron beam apparatus

A plurality of primary beams are formed from a single electron source, the surface charge of a sample is controlled by at least one primary beam, and at the same time, the inspection of the sample is conducted using a primary beam other than this. Also, for an exposure area of the primary beam for surface charge control and an exposure area of the primary beam for the inspection, the surface electric field strength is set individually. Also, the current of the primary beam for surface charge control and the interval between the primary beam for surface charge control and the primary beam for inspection are controlled.