Patent ID: 9324540
Filing Date: 2016-04-26
CPC Classification: H01J

Claim Text:
1. A charged particle beam device comprising: an electron source configured to generate a primary electron beam; an objective lens configured to focus the primary electron beam; a deflector configured to deflect the primary electron beam; a detector configured to detect a secondary electron or a reflection electron generated from a sample by irradiation of the primary electron beam; an electrode having a hole through which the primary electron beam passes; a voltage control power supply configured to apply a first negative voltage to the electrode; and a retarding voltage control power supply configured to generate an electric field, which decelerates the primary electron beam, on the sample by applying a second negative voltage to the sample, wherein the charged particle beam device performs focus adjustment by changing the first negative voltage applied to the electrode and the second negative voltage applied to the sample while maintaining a difference between the first and second negative voltages.