Synthesis of metastable epitaxial zinc-blende-structure AlN by solid-state reaction

Abstract

Epitaxial metastable zinc-blende-structure β-AlN was synthesized by the solid-state reaction between single-crystal Al(001) and TiN(001) layers grown on MgO(001) by ultrahigh vacuum magnetron sputter deposition. At an annealing temperature Ta=600 °C, the interaction proceeded according to the following overall reaction: 4Al+TiN→Al3Ti+AlN, in which β-AlN was formed pseudomorphically between cubic TiN and tetragonal Al3Ti layers. The lattice constant of β-AlN was found to be 0.438 nm, which corresponds to a 3.3% lattice mismatch with the underlying TiN layer.