Patent ID: 6838675
Filing Date: 2005-01-04
Classification: H01J

Abstract:
1. A specimen observation system for applying an external magnetic field to the specimen, said specimen observing system comprising: a source of a charged particle beam; a condenser optical system for radiating said charged particle beam onto a specimen; a specimen holder for holding the specimen to be observed on which the charged particle beam is radiated; a system for applying magnetic fields to the specimen in three orthogonal directions having the optical axis of the condenser optical system as one of the three directions; a front beam deflector disposed between the condenser optical system and the specimen holder for deflecting the charged particle beam away from the optical axis and then returning it to the optical axis such that the beam direction is in the direction of the optical axis when it illuminates the specimen; and a rear beam deflector disposed between the specimen holder and an imaging lens system, such that the deflector returns the charged particle beam to the optical axis after the beam passes through the magnetic fields applied to the specimen and such that the beam direction is in the direction of the optical axis, wherein the quantity and the direction of the deflection of the charged particle beam by the two beam deflectors are controlled according to the intensity and the direction of the magnetic fields applied to the specimen.