Toward epitaxial ternary oxide multilayer device stacks by atomic layer deposition

The authors demonstrate multilayer epitaxial films by atomic layer deposition and postdeposition annealing. Their example features two ABO₃ type perovskite oxide films with different materials properties—a conductor (LaNiO₃) and an insulator (SrTiO₃)—that can be integrated epitaxially once the geometric interaction between the two oxides' lattices is understood. Once preliminary epitaxial materials had been developed, the pilot multilayer device fabricated was an epitaxial metal-insulator-metal structure with layers of ∼5 nm thickness. This work shows the potential for advanced device types based on epitaxial atomic layer deposited films, assuming that care is taken in the selection of processes and starting substrate.