Design of a Low-Energy and High-Current-Density Ion Beam System in RF Source

Hydrogen ions with low energy around 100 eV are broadly utilized in material science as hydrogen implantation in multi-material integration or dry cleaning of material surface. A low-energy ion beam system is designed using a radio frequency (RF) source to extract high-density hydrogen ions with energy of 100 eV, consisting of the plasma generator and extraction system. A triode system is designed to extract ion beam and control ion energy by means of an accelerating-deaccelerating structure with about 4500 V potential drop. The ion beam optics is simulated through a particle trajectories code with the aim of reducing beam divergence and ion loss to extract high density ions, optimizing beam extraction characteristic for sensitive parameters. The results show that ion beam of a high density of 91.96 A/m2 with adjustable energy from 75 to 100 eV can be obtained by adjusting extraction electrode (EE) potential, sliming the thickness of EE and matching the radius of apertures carefully.