Measurement of Neutron-Induced Single-Event Upset Cross Section of UltraScale Kintex FPGA Using Time-of-Flight Technique

The correlation between neutron energy and neutron-induced soft error rate (SER) is crucial for estimating the impact on electronic devices fabricated using complementary metal-oxide-semiconductor (CMOS) technology in diverse neutron environments, including those found in high-energy physics experiments, aviation settings, and so on. This article presents an investigation conducted independently at China spallation neutron source (CSNS) using the Back-n white neutron source and atmospheric neutron irradiation spectrometer (ANIS) neutron source to directly measure single-event upset (SEU) effects of the configuration random access memory (CRAM) and block random access memory (BRAM) in 20-nm CMOS technology-based UltraScale Kintex FPGA. By recording the frequency of SEU events and the time of flight (TOF), SEU cross sections can be calculated for different energies. Experiment in situ indicates a coherent alignment of different outcomes under neutron irradiation from Back-n and ANIS, despite their different neutron energy spectra. The SEU threshold energy is estimated to be $0.69~\pm ~0.076$ MeV for CRAM and $0.80~\pm ~0.013$ MeV for BRAM. The measured cross sections can reach saturation of $6.9\times 10^{-15}$ cm2/bit and $1.6\times 10^{-14}$ cm2/bit for CRAM and BRAM, respectively, while the neutron energy is about 20 MeV.