  In this paper we show that state-of-the-art commercial off-the-shelf Flash
memory chip technology (20 nm technology node with multi-level cells) is quite
sensitive to ionizing radiation. We find that the fail-bit count in these Flash
chips starts to increase monotonically with gamma or X-ray dose at 100
rad(SiO2). Significantly more fail bits are observed in X-ray irradiated
devices, most likely due to dose enhancement effects due to high-Z
back-end-of-line materials. These results show promise for dosimetry
application.
