2004 Volume 45 Issue 7 Pages 1973-1977
Atomic structures characterization of Al2O3(0001)/Cu nano-hetero interfaces has been performed by the first-principles pseudopotential method and in cooperation with HRTEM observations. The physical properties of the interfaces depend strongly on the interface stoichiometry. Bonding nature of the O-rich (O-terminated) interface is explained as strong covalent and ionic interactions, whereas that of the stoichiometric (Al-terminated) interface is weak covalent and electrostatic image interactions. The O-terminated interface has quite larger adhesive energy than that of the stoichiometric one. Recent HRTEM observations of the Al2O3(0001)/Cu interface have confirmed the O-terminated interface. However, the observed incoherent interface is not the same as an ideal coherent interface obtained by the first-principles. We explain the relationship between the present coherent interface and the practical incoherent one.