Total Ionization Dose Effects on Charge Storage Capability of Al_2O_3/HfO_2/Al_2O_3-Based Charge Trapping Memory Cell

Because of the discrete charge storage mechanism, charge trapping memory (CTM) technique is a good candidate for aerospace and military missions. The total ionization dose (TID) effects on CTM cells with Al_2O_3/HfO_2/Al_2O_3 (AHA) high-k gate stack structure under in-situ 10 keV x-rays are studied. The C–V characteristics at different radiation doses demonstrate that charge stored in the device continues to be leaked away during the irradiation, thereby inducing the shift of flatband voltage (V_\rm fb). The dc memory window shows insignificant changes, suggesting the existence of good P/E ability. Furthermore, the physical mechanisms of TID induced radiation damages in AHA-based CTM are analyzed.