Comparative Study of the Single‐Event Functional Interrupt (SEFI) Rate in Solid‐State Drives (SSD) Through Ground and On‐Orbit Testing

Abstract Space radiation poses a significant threat to the reliability of spacecraft equipment, while traditional static space environment models exhibit substantial inaccuracies in calculating on‐orbit error rates. This study investigates single‐event functional interrupts (SEFIs) in commercial off‐the‐shelf (COTS) solid‐state drives (SSDs) operating in low Earth orbit utilizing real space environment data and AP9 model data. Using PHITS software, the internal radiation environment of the spacecraft was simulated based on external detector measurements and the AP9 model. Findings show that SEFI rates derived from measured spectra and the AP9 model at the 95% percentile closely match on‐orbit observations, whereas results based on spectra deviating from the real environment may differ by more than an order of magnitude. This research highlights the critical influence of the dynamic space environment on single‐event effects and emphasizes the importance of accounting for secondary neutron radiation in spacecraft design.