Multiple-Cell-Upsets on a commercial 90nm SRAM in dynamic mode

Downscaling of devices increases the Multiple-Cell-Upset (MCU) cross section of SRAMs making them an important threat for the robustness of systems. In this paper, we present different types of MCUs as they were recorded during atmospheric-like neutron irradiation experiments, during which a commercial 90nm SRAM was tested in dynamic mode. This study shows that when the memory is in dynamic mode, not only the typical MCU that involve a few flipped cells may appear but also, large clusters of upsets are possible to occur with hundreds of cells being affected. We identify different patterns of MCUs and categorize them according to their shapes and sizes.