Temperature acceleration of breakdown and quasi-breakdown phenomena in ultra-thin oxides

A study of the electric field and temperature dependence of the breakdown and quasi-breakdown phenomena is presented for 3.5 nm ultra-thin SiO2 gate oxides. Using methodology based on the competing mecanism concept between breakdown and quasi-breakdown processes, quasi-breakdown activation energy as well as acceleration factor are determined. It is demonstrated on these 3.5nm gate oxides that the quasi-breakdown temperature activation energy is almost temperature independent on the contrary to the breakdown one. Moreover, it has been shown that the temperature dependence of the breakdown acceleration factor and the electric field dependence of the temperature activation energy cannot be explained by a pure "E" and "1/E" models, but can be interpreted by the "E" model if at least two types of molecular defect states are considered. (C) 1999 Elsevier Science Ltd. All rights reserved.