Ballistic Missile System Innovative Radiation Hardened/Tolerant Electronics Products

Data for on-orbit performance of COTS ICs that are spot-shielded with high-Z material have recently shown unexpected results. Total-dose induced leakage current in FPGAs on the MPTB satellite was significantly higher in devices shielded with high-Z material than similar unshielded devices. These unexpected results indicate that the technical community may have an incomplete understanding of all the factors involved in using spot shields on ICs in space. This program will provide a focused and comprehensive study to resolve this anomaly. The effort will include 3 major thrusts: 1. Ground testing of appropriate devices with spot shield variations. 2. Modification of appropriate transport codes to better account for secondary particle effects in IC devices. 3. Development of a space experiment designed specifically for evaluating spot shielding effectiveness for total-ionizing-dose effects. The space experiment will be targeted for the NASA Living With a Star / Space Environment Tested (LWS/SET) program. At the end of the Phase II effort, we will have a focused space experiment that is designed, fabricated, and supported by ground test data and improved modeling capability. The space experiment will then be ready for implementation on an appropriate space experiment program.