Neutron production targets for a new Single Event Effects facility at the 70 MeV Cyclotron of LNL-INFN

A high-current (500 μA) variable energy (35-70 MeV) proton cyclotron is under construction at the INFN LNL for the SPES project and will be commissioned in 2014. This opens up the prospect of a high flux neutron irradiation facility in Italy that could perform various research activities, in particular studies of Single Event Effects (SEE) induced in microelectronic devices and systems by atmospheric neutrons at sea level. In this paper we first review neutron-induced SEE, describe neutron testing facilities and briefly illustrate the project at LNL. We then describe two types of high power production targets under design to produce neutrons with a continuous atmospheric-like differential energy spectra in the energy range accessible to the accelerator. One target is a high power W-based thick target that will completely stop the 70 MeV protons. Another target, under preliminary study, is based on a multi-material target made, in this case, of two different materials, light (Be) and a heavy material such as Ta or Pb.