CU + ION EXTRACTION FROM A MODIFIED BERNAS ION SOURCE IN A METAL-ION IMPLANTER

An ion implanter, which can serve as a metal-ion supply, has been constructed and performance tested. Copper ions are generated and extracted from a Bernas ion source with a heating crucible that provides feed gases to sustain the plasma. Sable arc plasmas can be sustained in the ion source for a crucible temperature in excess of 350°C. Stable extraction of the ions is possible for arc currents less than 0.3 A. Arc currents increase with the induced power of a block cathode and the transverse field in the ion source. Cu+ ions in the extracted beam are separated using a dipole magnet. A 20 μA Cu+ ion current can be extracted with a 0.2 A arc current. The ion current can support a dose of 10 16 ions/ cm 2 over an area of 15 cm 2 within a few hours.