Patent ID: 10840070

Abstract:
An ion beam device according to the present invention suppresses the fluctuation of an ion emission current by cleaning the inside of a chamber without entailing wear damage to an emitter electrode. The ion beam device includes a GFIS including an emitter electrode having a needle-shaped tip; an extraction electrode having an opening at a position spaced apart from the tip of the emitter electrode; and a chamber encapsulating the emitter electrode therein. The GFIS includes an ionizable gas introduction path for introducing an ionizable gas into the chamber in a state where a voltage equal to or more than a beam generating voltage is applied to the emitter electrode; and a cleaning gas introduction path for introducing a cleaning gas into the chamber in either a state where a voltage less than the beam generating voltage is applied to the emitter electrode or a state where no voltage is applied to the emitter electrode. A pressure of the chamber with the cleaning gas introduced therein is higher than a pressure of the chamber when the ionizable gas is introduced therein.