The reaction of O2 with Al(110): a medium energy ion scattering study of nano-sc

2020-02-12 11:50:17

The ion oxidation Oxygen oxide

责任者: Starodub, D.;Gustafsson, T.;Garfunkel, E. 单位: Dept. of Phys. & Astron., Rutgers Univ., Piscataway, NJ, USA 来源出处: Surface Science(Surf. Sci. (Netherlands)),2004/03/10,552(1-3):199-214 摘要: We have used medium energy ion scattering to study oxygen transport and oxidation kinetics of Al(l10) at elevated temperatures in dry oxygen. Oxidation results in the formation of a stable stoichiometric Al2O3 layer with fairly abrupt interfaces. The time dependence of the film growth follows inverse logarithmic law, in agreement with the Cabrera-Mott (field-assisted) oxidation mechanism. The dependence of the growth rate on pressure is parabolic. Microscopic details on oxidation mechanism are studied by re-oxidizing a thin oxide layer with isotopically labeled oxygen. The depth profiling of oxygen traces in the oxide shows that oxygen ions are mobile species transported via migration of oxide network defects. This migration across the film is the rate-limiting step controlling oxidation 关键词: alumina;chemical exchanges;oxidation;reaction kinetics;surface chemistry;thin films;medium energy ion scattering;nanoscale oxidation;oxygen transport;oxidation kinetics;stable stoichiometric Al2O3 layer;Cabrera-Mott oxidation mechanism;inverse logarithmic law;oxide network defects;Al2O3