ION SHOWER APPARATUS

摘要

An ion shower apparatus comprising a plasma formation chamber in which plasma is produced so as to produce ions, a single ion extraction grid disposed in one portion of the plasma formation chamber and for extracting the ions from the plasma formation chamber so as to form an ion beam in the form of shower, a specimen chamber in which the surface of a specimen subjected to etching or deposition or a target subjected to sputtering is irradiated with the ion beam in the form of shower, and a shield grid disposed in the vicinity of the ion extraction grid in the plasma formation chamber and spaced apart from the thickness of the plasma sheath produced over the ion extraction grid, in a manner that the shield grid permits the passage of the plasma therethrough and prevents the electric field produced by the ion extraction grid substantially from extending to the remaining region of the plasma formation chamber. The ion extraction grid is not damaged. An ion beam with a high current is obtained stably.