Charge Retention Improvement of Nonvolatile Radiation Sensor Using Metal-Oxide-Nitride-Oxide-Silicon with Si-Rich Nitride and Oxy-Nitride as Stack Charge-Trapping Layer

Metal-oxide-nitride-oxide-silicon devices with Si-rich nitride and oxy-nitride as a bi-layer stack charge-trapping layer (hereafter STOB-MONOS) could be candidates for nonvolatile total ionizing dose (TID) radiation sensors. In the case of STOB-MONOS nonvolatile TID radiation sensors, gamma radiation induces a significant decrease in the threshold voltage V-T, which is nearly 2 times larger than that of a standard MONOS device. The change in V-T for STOB-MONOS after gamma irradiation also has a strong correlation to TID up to 10 Mrad gamma irradiation. The reliability characteristics of VT retention time before and after gamma irradiation for STOB-MONOS devices can be markedly improved and is nearly 12% better than that of a standard MONOS device. The STOB-MONOS device in this study has demonstrated the possibility of improved the feasibility of non-volatile high TID radiation sensing.