Article

Logistic model for leakage current in electrical stressed ultra-thin gate oxides

Dipt. di Ingegneria dell' Informazione, Univ. degli Studi di Padova, Italy
Electronics Letters (Impact Factor: 1.04). 06/2003; DOI: 10.1049/el:20030485
Source: IEEE Xplore

ABSTRACT It is shown that the leakage current flowing through an ultra-thin gate oxide in a metal-oxide-semiconductor structure subjected to a constant voltage stress can be described by a Verhulst-type logistic model. An exponential growth at the outset is followed by a saturation in the conduction characteristic, which indicates that, after a rapid expansion, the damaged area reaches an upper bound. This sigmoidal behaviour is interpreted as a self-constrained growth of the leakage site population.

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