Charged particle beam apparatus sample holder with magnetic field generating element and sample holding element

A charged particle beam apparatus comprising:

• an irradiation optical system that irradiates a sample with a charged particle beam;
• a magnetic field generating element including three or more magnetic circuits, each having a respective magnetic gap for applying a magnetic field to the sample;
• a cantilever-beam-shaped sample holding element that holds the sample on one end thereof;
• and
• a moving mechanism that adjusts a relative position between the sample and the magnetic gaps to selectively position the sample within any one of the magnetic gaps for observation of the sample irradiated in a mode in which the magnetic field of the one gap is applied to the sample in a direction perpendicular to an optical axis of the charged particle beam, and to position the sample outside the magnetic gaps for observation of the sample irradiated in a mode in which no magnetic field is applied to the sample by the magnetic gaps.