Production of various species of focused ion beam

The ability to generate various ion species makes the multicusp plasma ion source an excellent candidate for maskless resistless lithography application. In this article, the mass spectra of both positive and negative ions for phosphorus, ${\mathrm{BF}}_{\mathrm{3}},$ and oxygen multicusp plasmas are presented. It is shown that over 90% ${\mathrm{P}}^{\mathrm{+}}$ ions are produced. The production of ${\mathrm{BF}}_{\mathrm{2}}^{\mathrm{+}}$ and ${\mathrm{O}}_{\mathrm{2}}^{\mathrm{+}}$ increases with increasing gas pressure, and decreases with increasing source power. With optimization of source operating parameters, approximately 85% ${\mathrm{BF}}_{\mathrm{2}}^{\mathrm{+}}$ and over 90% ${\mathrm{O}}_{\mathrm{2}}^{\mathrm{+}}$ have been achieved.