Characterization of Conical Anode: Disc Cathode Ion Source with Radial Extraction
The main goal of this work is to study the effect of pierce angle (67.5°) of cone anode head, the exit of ion beam in a radial direction and the range of nitrogen gas operating pressure on the output ion beam current. It was found that a maximum ion beam current can be obtained in radial direction than that ion beam in axial direction which obtained in the previous study. So that a direct current conical anode-disc cathode ion source with radial extraction was designed, constructed and operated. The optimum head angle of conical anode, ion exit aperture diameter and ion exit aperture - Faraday cup distance was determined at the ion source optimum dimensions obtained previously using nitrogen gas. The electrical discharge and the output ion beam current characteristics were measured at the optimum dimensions operating conditions. It was found that at the optimum operating conditions 3 × 10-4 mmHg pressure, 3 kV discharge voltage and 2.2 mA discharge current, a maximum output ion beam current equal to 700 μA can be obtained. Hence, the ion source efficiency at that optimum operating conditions and discharge current equal to 0.8 mA was equal to 45%. Therefore, a comparison between the axial output ion beam current obtained in the previous study and the radial output of ion beam current measured in this study were done. Also, the effect of annealing and nitrogen ion beam irradiation on the d.c. electrical properties and micro hardness of hostaphan samples were determined.