Isotopic labeling study of oxygen diffusion in amorphous LaScO3 high-κ films on Si(100) and its effects on the electrical characteristics

The influence of post-deposition oxygen anneals on the properties of amorphous LaScO3 films on Si(100) is reported. The use of an isotopically (18O2) enriched atmosphere allowed to investigate the 16O–18O exchange and the oxygen diffusion across the dielectric layer. Such effects are connected to the formation of an interfacial layer. Oxygen annealing leads to nearly ideal capacitance–voltage curves, lower leakage currents and interface trap densities, as well as to κ-values up to 33 for the LaScO3 films. These results are attributed to the suppression of oxygen-related trap centers and the achievement of a stoichiometric oxygen content.