D-C DIELECTRIC BREAKDOWN OF AMORPHOUS SILICON DIOXIDE FILMS AT ROOM TEMPERATURE

The dielectric breakdown properties of atmospheric pressure steam-grown silicon dioxide films, grown on fresh epitaxial layers with degenerate silicon substrates, were studied at room temperature as a function of d-c voltage, time, polarity, thickness of the oxide, and rate of change of voltage. Contact was made to the oxide by 0.025 in. diameter evaporated gold dots. The observed phenomena were found to depend basically on the polarity of the applied potential. At positive silicon potentials (gold dots negative) dielectric breakdown occurred abruptly with no detectable conduction below breakdown. Positive breakdown is not time dependent and appears to be of the type generally referred to as intrinsic or disruptive breakdown. At negative silicon potentials (gold dots positive) these films exhibited conduction in the na range and a time dependence of dielectric breakdown. If t is the time it takes an oxide to breakdown at an applied voltage V, a linear relationship between V and t−1/4 is observed over a range of approximately 150v. This is an empirical relationship known as Peek's law. © 1968, The Electrochemical Society, Inc. All rights reserved.