his work reports both experimental and theoretical results of the depopulation kinetics of electron traps in silicon oxides annealed in ammonia ambient at a temperature of 1050 degree(s)C for 30, 60, or 180 min. Results show a significant modification of the spatial and energy distribution of traps in oxynitride after employing a heavy nitridation. Specifically, we found that sample with longer annealing duration has large depopulation rate and is more sensitive to the electric field than the sample with a shorter period of annealing. In addition, the nitrided oxides were found to have only a small percentage of traps with shallow energy levels (< 1 eV) and the percentage remains fairly unchanged for different nitridation conditions. However, the deeper traps (> 1 eV) increase significantly as the nitridation proceeds. By considering the re-trapping effect and the spatial and energy distributions of traps, a new depopulation theory of the electron traps in thin oxynitride is developed and most of the experimental observations can be explained with the present model.
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