Production of atomic or molecular nitrogen ion beams using a multicusp and a microwave ion source

Two small ion sources have been used to generate positive nitrogen ion beams. One is a multicusp ion source, the other is a compact microwave ion source which needs no magnetic field for operation. Both sources are operated with and without a magnetic filter to control the energetic electron population near the extraction region. Results for both ion sources, including current densities and ionic species mix are presented. The multicusp ion source can produce beams of nitrogen ions with greater than 90% of the ion species either N+ or N+2 with current densities of ∼8 and 2.5 mA/cm2, respectively. The microwave ion source can generate nitrogen ion beams composed of more than 85% N+2 with current densities of ∼30 mA/cm2