Optimal conditions for high current proton irradiations at the university of Wisconsin's ion beam laboratory


The National Electrostatics Corporation’s (NEC) Toroidal Volume Ion Source (TORVIS) source is known for exceptionally high proton currents with minimal service downtime as compared to traditional sputter sources. It has been possible to obtain over 150$\mu$A of proton current from the source, with over 70$\mu$A on the target stage. However, beam fluxes above ∼1×10 17/m2-s may have many undesirable effects, especially for insulators. This may include high temperature gradients at the surface, sputtering, surface discharge, cracking or even disintegration of the sample. A series of experiments were conducted to examine the role of high current fluxes in a suite of ceramics and insulating materials. Results will show the optimal proton irradiation conditions and target mounting strategies needed to minimize unwanted macro-scale damage, while developing a procedure for conducting preliminary radiation experiments. \textcopyright 2013 AIP Publishing LLC.

In: AIP Conference Proceedings, pp. 649–653