Charged particle beam device and sample observation method

A charged particle beam device that observes a sample, the device comprising:

• a primary electron optical system for irradiating a plurality of charged particle beams onto a sample;
• a first detector for detecting a secondary charged particle beam generated from the sample;
• and
• a control unit for controlling the primary electron optical system, switching the number of a plurality of the charged particle beams, and selecting a multi-beam mode and a single beam mode,
• wherein the control unit includes an observation condition setting unit for setting an observation condition, a switching condition setting unit for setting a switching condition for switching the number of a plurality of the charged particle beams, and a switching control unit for switching the number of a plurality of the charged particle beams on the basis of the switching condition.

A sample observation method using a charged particle beam device which includes a primary electron optical system for irradiating a plurality of charged particle beams onto a sample, a detector for detecting a secondary charged particle beam generated from the sample, and a control unit for controlling the primary electron optical system and observes the sample, the sample observation method comprising:

• setting an observation condition of the sample;
• and
• setting a switching condition for switching the number of a plurality of the charged particle beams to select a multi-beam mode and a single beam mode,
• wherein the control unit controls the primary electron optical system and switches the number of the charged particle beams by the set switching condition, and the control unit observes the sample.