Patent ID: 6753518
Filing Date: 2004-06-22
Classification: B82Y,H01J

Abstract:
An electron beam apparatus, comprising:a table which mounts a specimen and is movable in three dimensional directions; an electron optical system including an electron beam source, an element for deflecting an electron beam emitted from the electron beam source, an objective lens for converging and irradiating the electron beam deflected by the deflection element onto a specimen mounted on the table and a detector for detecting a secondary electron emanated from the specimen by the irradiation of the electron beams; a surface height detection unit which optically detects a height of a surface of the specimen by projecting light onto the surface of the specimen from an oblique direction to the surface and detecting light reflected from the specimen mounted on the table which is continuously moved; and a focus controller which controls a relative position of the table in a height direction while the table is continuously moved between a focus position of the electron optical system and the table in accordance with information of the height from the surface height detection unit.