Patent ID: 8766185

Claim:
A charged particle beam device, comprising; an irradiation optical system for irradiating a charged particle beam to a sample to be observed; an imaging optical system for imaging a charged particle beam emitted or reflected from the sample; a power supply unit for applying a first DC voltage to the sample; a base stage for moving the sample; a rotary stage for rotating the sample on the base stage; a sample holder disposed on the rotary stage for holding the sample, and a sample electric field control electrode that is provided in the outer periphery of the rotary stage, being independent from the rotary stage, for varying an equipotential plane on the sample, wherein, when the sample is held on the sample holder, a gap exists between the sample and the sample electric field control electrode mechanism, wherein the sample electric field control electrode has applied thereto a second DC voltage from the power supply unit and is provided along the outer circumference of an edge of the sample, when the sample is held on the sample holder, wherein the sample electric field control electrode applies the second DC voltage for varying the equipotential plane in accordance with the rotation of the rotary stage during imaging with the charged particle beam, and wherein the sample electric field control electrode makes the equipotential plane on the sample horizontal as far as the edge of the sample by varying the equipotential plane at the gap, the charged particle beam device further comprising: an electric field control plate that surrounds the periphery of the sample and is disposed on the sample holder, an insulator provided between the sample holder and the electric field control plate, a charge control electron gun for charging the electric field control plate by irradiating an electron beam to the electric field control plate, and an ultraviolet light source for neutralizing the electric field control plate by irradiating ultraviolet rays to the electric field control plate, wherein the voltage of the electric field control plate is controlled by electron beam irradiation with the charge control electron gun and by ultraviolet ray irradiation with the ultraviolet light source.