Patent ID: 8552397

Claim:
A focused ion beam apparatus comprising: a sample stage which mounts a sample; an ion source which discharges an ion beam; an aperture which narrows down the ion beam discharged from the ion source; a condenser lens which is a first electrostatic lens, and which is located upstream of the aperture; a tilting deflector which deflects the ion beam passed through the aperture; a beam scanner which scans the ion beam passed through the tilting deflector; an objective lens which is a second electrostatic lens, and which irradiates the ion beam passed through the beam scanner on a sample; and a control device which controls the aperture, the tilting deflector, the beam scanner, the objective lens, and the condenser lens, wherein the ion beam has no intermediate convergence point between the objective lens and the condenser lens during processing with a vertical beam or observing with the vertical beam, and wherein, if a tilted beam is selected, the control device causes the ion beam to have the intermediate convergence point, the aperture to be moved out of an optical axis, the tilting deflector to deflect the ion beam in the same direction as the aperture is moved, the ion beam to pass through the objective lens out of the optical axis, and the ion beam tilted to the optical axis to be irradiated on the sample.