CONVERGED ION BEAM DEVICE

PROBLEM TO BE SOLVED: To provide a converged ion beam device provided with a liquid metal ion source for realizing accurate measurement of an emission current and generation of a stable ion beam. SOLUTION: Extraction electrodes of the liquid metal ion source are provided in a vertical double stages with a space therebetween, and integrated. Respective center holes (ion beam passing holes) of the upper electrode 32A and the lower electrode 32B of the extraction electrodes, and a lens electrode 33A are formed to satisfy the following conditions (1)-(3), where ΩEM represents the emission maximum solid angle of emission, ΩEXU represents an extraction upper electrode solid angle, ΩEXL represents an extraction lower electrode solid angle, and ΩCL represents a lens electrode solid angle. ΩEMΩEXL (2), ΩEXL