Total ionization dose effects on the charge storage capability of Er2O3/HfO2/Er2O3 based memory cell

Co-60 gamma radiation effects on the charge storage capability of the Er2O3/HfO2/Er2O3 based charge trapping memory (CTM) cell were studied in detail. In addition, the structural and electrical characteristics of the CTM cell were also analyzed. Transmission Electron Microscopy (TEM) was used to analyze the structural characteristics of the CTM cell. To analyze the electrical characteristics of the cell, Capacitance-Voltage (C-V) and Conductance-Voltage (G/w-V) measurements were taken for CTM cell samples left as-deposited, and those annealed at 3500C and 7000C. The memory window was seen to increase with increasing post- deposition annealing (PDA) temperature which was attributed to an increase in the oxide trap charges. 7000C was chosen as the optimum PDA temperature because the CTM cell annealed at this temperature possessed the largest memory window and a high oxide capacitance. Gamma radiation was then used to analyze the radiation effects on the electrical characteristics of the CTM cell. The Er2O3/HfO2/Er2O3 based CTM cell was found to be promising for radiation environments.