The experiments confirm that the charge to breakdown QBD, often used for oxide monitoring, is closely related to the positive space charge formed in the bulk of the oxide layer during electron injections. The results are justified by assuming that breakdown occurs when a critical net and effective number of charges per unit area, NC equals 5 1012 cm-2, is reached in SiO2 layers. An interpretation of breakdown induced by a positive charge is proposed, based on the polarization/relaxation process previously used to explain the electron charge induced breakdown process.
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