Tailoring the Internal Evaporator for Effective Ion Beam Production - Volatile vs. Non-Volatile Substances

Two different designs of the internal evaporator in an arc discharge ion source are presented, suitable either for volatile, or high-melting point substances. A matter of the evaporator size and placement in order to obtain its appropriate temperature and, therefore, a stable and intense ion beam, is considered. Basic ion source characteristics, i.e. the dependences of ion current and discharge voltage on the discharge and filament currents as well as on the external magnetic field flux density are shown and discussed in order to find optimal working conditions. The results of measurements for both volatile (P, Zn, Se, S) and non-volatile (Pd) are presented, showing the applicability of the design for ion implantation purposes.