Applications of heavy-negative-ion sources for materials science (invited)

Abstract

Applications of heavy negative ions produced by sputter-type negative-ion sources for materials science are reviewed. Submilliampere and milliampere heavy-negative-ion beams can be produced by a neutral- and ionized-alkaline–metal-bombardment-type heavy-negative-ion source and rf plasma sputter-type negative-ion sources, respectively. These negative-ion beams can be applied for materials processing such as ion implantation, ion beam etching, and ion beam deposition. In negative-ion implantation the charge-up of implanted material surfaces is greatly reduced, and thus ion implantation without target charging is possible. The etching rate due to fluorine-negative ion is mainly determined by its kinetic energy. Pure diamondlike carbon films with high sp[3] structure have been prepared by C[−] and C_2[−]ion beam deposition, and CN films by CN[−]ion beam deposition. Negative ions provide an excellent tool for materials processing applications.