title: Effects of a dielectric material in an ion source on the ion beam current density and ion beam energy.
abstract: To understand a strong focusing phenomenon that occurs in a low-energy hydrogen ion beam, the electron temperature, the electron density, and the space potential in an ion source with cusped magnetic fields are measured before and after the transition to the focusing state using an electrostatic probe. The experimental results show that no significant changes are observed before or after the transition. However, we found unique phenomena that are characterized by the position of the electrostatic probe in the ion source chamber. Specifically, the extracted ion beam current density and energy are obviously enhanced in the case where the electrostatic probe, which is covered by a dielectric material, is placed close to an acceleration electrode.
authors.affiliation: Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Fujiwara
authors.affiliation: Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sakakita
authors.affiliation: Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Nakamiya
authors.affiliation: Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki 305-8568, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hirano
authors.affiliation: Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki 305-8568, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kiyama