Diagnosis of pulsed heavy ion beam by magnetically insulated ion diode

A magnetically insulated ion diode with an active ion source of a gas puff plasma gun has been developed in order to generate a high-intensity pulsed heavy ion beam for the implantation process of semiconductors and the surface modification of materials. When the ion diode was operated at diode voltage approx. = 190 kV, diode current approx. = 15 kA and pulse duration approx. = 100 ns, the ion beam with an ion current density of 54 A/cm2 was obtained at 50 mm downstream from the anode. It was found from the evaluation of ion species and energy of the ion beam by a Thomson parabola spectrometer (TPS) that N+ and N2+ beams of 100-300 keV energy were accelerated with proton impurities of 90-190 keV energy. The purity of the beam was estimated to be 94%. In addition, to produce the pulsed metallic ion beam we developed the By type ion diode using a vacuum arc plasma gun instead of the gas puff plasma gun. The aluminum ion beam with an ion current density of 53 A/cm2 was obtained at 50 mm downstream from the anode. We found from TPS measurement that the ion beam consisted of the Al2+ and Al3+ beams with the energy of 100-300 keV and the proton impurities with the energy of 110-170 keV. (author)