Thin piece specimen preparing method and composite charged particle beam device

摘要

At the same time as making a lamina by performing a sputtering etching working of a 1st focused ion beam 101, a scanning ion microscope observation is made by performing an irradiation of a 2nd focused ion beam 102 from a direction parallel to a side wall of the lamina, thereby measuring a thickness of the lamina. And, the working by the focused ion beam is finished by confirming the fact that the thickness of the lamina has become a predetermined thickness.