SEE sensitivity of a COTS 28-nm SRAM-based FPGA under thermal neutrons and different incident angles

This paper provides an experimental study of the single-event upset (SEU) susceptibility against thermal neutron radiation of a 28-nm bulk Commercial-Off-The-Shelf (COTS) Xilinx Artix-7 FPGA under different angles of incidence. Experimental results indicating SEUs on configuration RAM (CRAM) cells, Flip-Flops (FFs), and Block RAMs (BRAMs) are presented and discussed. Shapes of multiple events (ranging from 2 to 12-bit) are also analyzed, and their dependency on the incident angle of the particle beam against the device’s surface. Possible shapes of 128 and 384-bit multiple events are also investigated, revealing a trend to follow word lines. The results of the front incident angle are compared with 14.2-MeV neutrons, demonstrating a considerable difference in the device’s sensitivity against both irradiation sources. Finally, a modeling tool called MUSCA-SEP3 is used to predict the device’s sensitivity under the same environmental conditions. The obtained experimental results will show a good agreement with the predicted ones in a very accurate way.