Conservation and filling of neutral hole traps in SiO2 during ionizing radiation exposure

The question of whether ionizing radiation creates fixed positive charge and/or neutral hole traps, or simply fills existing neutral hole traps has been examined by equating the density of intrinsic neutral hole traps, present before irradiation, with the sum of fixed positive charge and the remaining neutral hole traps present after x‐ray irradiation. The total number of positive Coulombic and neutral hole traps was found to remain constant, regardless of the level of radiation the device receives. This indicates strongly that fixed positive charge represents filled intrinsic hole traps and that additional hole trapping defects, except for a small amount of fixed negative charge, are not generated by ionizing radiation in the photon energy range studied.