TID Testing of SiGe Microelectronics Using High-Flux 1-MeV Electrons for Europa-Surface Missions

Europa lies in Jupiter’s colossal radiation belt, producing radiation surface conditions that are so severe (5 Mrad[Si]) that most modern electronics would experience degradation in a matter of days. This challenge, coupled with the sub-100 K surface temperatures, leads to a very hostile environment for a viable electronic infrastructure. To help enable a future mission for landing on Europa’s surface, there must be efficient terrestrial testing facilities in place to model the effects of the environment on the requisite microelectronics. The Jet Propulsion Laboratory’s Dynamitron facility, an electrostatic particle accelerator, provides unique TID testing capabilities with high flux, high energy electrons at both room (300 K) and at cryogenic (100 K) temperatures. We have found that radiation test methods for microelectronics require additional considerations in the high flux, high energy, cryogenic environment within the chamber. This paper outlines the best practices required for success, and demonstrates the efficacy of these methods using silicongermanium (SiGe) microelectronic devices and circuits, a leading candidate technology for Europa surface missions.