Amorphous Lanthanum Lutetium Oxide Thin Films as an Alternative High-k Material

Abstract

Lanthanum lutetium oxide thin films have been grown on Si substrates by three different techniques: pulsed-laser deposition, molecular beam deposition, and atomic layer deposition. Post-deposition annealing in O2 was performed to improve their electrical properties. Capacitance-voltage and current-voltage measurements reveal well-behaving C-V curves and low leakage current density levels. Most strikingly, a dielectric constant around 30 could be achieved for amorphous thin films of this material. These results are discussed in terms of the microstructural characteristics of the films before and after thermal treatment.