Interfacial Reactions During Processing of Thin Nickel Oxide Films Grown by Pulsed-Laser Ablation

Abstract

ABSTRACTThe study of oxide solid-state reactions is a natural application for pulsed-laser ablation (PLA) because high quality films of virtually any oxide composition can be fabricated. In this study, the effect of interfacial morphology on reaction kinetics in the model oxide system of nickel oxide (NiO) and alumina (α-Al2O3) is investigated. Thin films of NiO have been grown on single-crystal substrates of basal (0001) α-Al2O3 by PLA in order to study the initial stages of the nickel-aluminate spinel (NiAl2O4) phase transformation. The initial state, a 100 nm NiO film on (0001) α-Al2O3, is characterized with both plan-view and cross-section transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The final state of the spinel reaction layer between the NiO and α-Al2O3 after various heat-treatments is also characterized by the same techniques.