Patent ID: 7154089
Filing Date: 2006-12-26
Classification: H01J

Abstract:
1. A scanning electron microscope comprising: a specimen stage for holding a specimen, an objective lens for radiating a converged primary electron beam on the specimen, a secondary electron detector for detecting the secondary electrons generated from the specimen by the radiation of the electron beam thereon, a first electrode, arranged under the objective lens, to which negative voltage is applied to form electric field for repelling the secondary electrons emitted from said specimen on a side of the specimen; and a second electrode, arranged between said first electrode and said secondary electron detector and on an outer peripheral side of said first electrode in relation to a primary electron beam radiation port of said objective lens, to which positive voltage is applied to form electric field for attracting the secondary electrons repelled by said first electrode; wherein said secondary electron detector is arranged on an outer peripheral side of said second electrode in relation to said primary electron beam radiation port and on a trajectory of said secondary electrons repelled by said first electrode and attracted by said second electrode.