Investigation of intense pulsed ion beam generation by a magnetically insulated ion diode at a reduced impedance

Abstract

The intense pulsed ion beam (IPIB) generation was investigated at reduced impedance of a magnetically insulated ion diode. The main goal of our research was to obtain IPIB with adjustable parameters at low current densities. The diode impedance was varied by the external magnetic field current by setting the delay of the accelerator's trigger relative to the launch of the magnetic field generator. The B-applied ion diode adjustably generated IPIB with a current density in the range from 25 to 4 A/cm2. In the matched mode the accelerator generates the ion beam with a current density of about 100 A/cm2. Obtained results of the IPIB current density adjustment allows to irradiate samples in a single vacuum cycle without the change of charging voltage of both magnetic field and accelerating voltage generators. Gold films with a thickness of 10 nm deposited on fluorine-doped tin oxide (FTO)/glass substrates were irradiated to demonstrate the applicability of obtained IPIB for irradiation of thin coatings without their deterioration. Single shot of IPIB with current density of 20 A/cm2 transformed Au film to spherical micro-particles, while after irradiation at the same fluence with 5 pulses of IPIB with current density of 4 A/cm2 Au coating was preserved as a film.