Field dependent charge trapping effects in SIMOX and buried oxides at very high dose

SIMOX (separation by implantation of oxygen) devices have been irradiated at up to 100 Mrad under different positive and negative back-gate voltages. At low cumulated dose, hole trapping is controlled by external applied field. For higher doses up to 100 Mrad, the early positive net charge is compensated mainly by electron trapping. Nevertheless, at weak fields, no evidence of positive charge compensation is observed. Interface state buildup appears at very high dose (>10 Mrad) for the set of biases used, but influences slightly V/sub tb/ shift. The trapped hole recombination effect also occurs, but seems significant only for negative biases in the numerical approach. Furthermore, annealing data reveal a complex structure of traps that requires further investigations.<
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