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Title: Heuristic Detection of the Most Vulnerable Regions in Electronic Devices for Radiation Survivability
As electronic systems become larger and more complex, detection of the most vulnerable regions (MVR) to radiation exposure becomes more difficult and time consuming. We present a heuristic approach where the mechanical and thermal aspects of devices are exploited to quickly identify MVRs. Our approach involves the topological mapping of two device conditions. The first condition identifies regions with the highest mechanical strain or density of defects and interfaces via thermal wave probing and phase analysis. The second condition identifies regions with high electrical field. It is hypothesized that the region with the highest thermal wave penetration resistance and electrical field will exhibit the highest sensitivity to incoming radiation for single events and potentially, total ionizing dose. Our approach implements a simplistic design that improves analysis time by ∼2–3 orders of magnitude over current radiation sensitivity mapping methods. The design is demonstrated on the well-studied operational amplifier LM124, which shows agreement with the literature in identifying sensitive transistors–QR1, Q9, and Q18–with relatively high phase percentile values (>70%) and ΔT percentiles (>50%), satisfying conditions for elevated radiation susceptibility. This is followed by experimental results on a static random access memory (HM-6504) and a Xilinx Artix-7 35 T system on a chip.
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ECS Journal of Solid State Science and Technology
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National Science Foundation
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