Patent ID: 7952083

Claim:
An ion beam system, comprising: a sample stage which holds a sample; an ion source which generates an ion beam so that the ion beam is extracted from the ion source along an extraction axis; an irradiation optical system having an irradiation axis along which the ion beam is irradiated toward the sample held on the sample stage so as to form a non-axially symmetric beam spot with a long axis on a surface of the sample; and a charged particle beam irradiation system for observing the surface of the sample which is machined by the irradiated ion beam; wherein the extraction axis along which the ion beam is extracted from the ion source and the irradiation axis along which the sample is irradiated are inclined with respect to one another; and wherein a segment which is a projection of an inclination direction of the extraction axis on a sample holding surface of the sample stage and a segment which is a projection of the long axis of the beam spot on the sample holding surface of the sample stage extend in parallel to one another.