Abstract
Molecular dynamics simulations employing dynamic charge transfer between atoms indicate a significantly enhanced rate of Al(100) oxidation by O2 and O at 300 K in the presence of an electric field. Increasing the electric field (approximately 10(7) V/cm) drives the surface chemisorbed oxygen to the vacancy sites in the oxide interior leading to dramatic density and stoichiometry improvements of the grown ultrathin oxide film. The associated oxidation kinetics enhancement due to the applied electric field is postulated to arise from the activation barrier lowering at electrostatic potentials approaching the Mott potential and beyond, leading to a dramatically increased ion migration through oxide film. The results are of significance to understanding mechanisms of early stage oxide growth as well as technologies utilizing ultrathin oxides.
Highlights
The Harvard community has made this article openly available
Increasing the electric field ($107 V=cm) drives the surface chemisorbed oxygen to the vacancy sites in the oxide interior leading to dramatic density and stoichiometry improvements of the grown ultrathin oxide film
The associated oxidation kinetics enhancement due to the applied electric field is postulated to arise from the activation barrier lowering at electrostatic potentials approaching the Mott potential and beyond, leading to a dramatically increased ion migration through oxide film
Summary
In the case of electron enhanced oxidation, most of the experimental kinetic data have been explained on the basis of the Mott-Cabrera theory, which postulates that the electrostatic field formed across a growing oxide film promotes ion migration—the limiting step for mass transport in oxidation, leading to a rapid and more uniform oxide-film growth [11] This basic model does not consider the effects arising from the defects or disorder in the oxide layer and does not take into account the atomistic processes occurring at the metal surface, in the developing oxide film, and at the metal-oxide and oxide-gas interfaces. To the best of our knowledge, the differences between the amorphous oxide scale formed under various simulated electric
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
