Structural Properties Characterized by the Film Thickness and Annealing Temperature for LaO Films Grown by Atomic Layer Deposition.

LaO films were grown on Si substrates by atomic layer deposition technique with different thickness. Crystallization characteristics of the LaO films were analyzed by grazing incidence X-ray diffraction after post-deposition rapid thermal annealing treatments at several annealing temperatures. It was found that the crystallization behaviors of the LaO films are affected by the film thickness and annealing temperatures as a relationship with the diffusion of Si substrate. Compared with the amorphous LaO films, the crystallized films were observed to be more unstable due to the hygroscopicity of LaO. Besides, the impacts of crystallization characteristics on the bandgap and refractive index of the LaO films were also investigated by X-ray photoelectron spectroscopy and spectroscopic ellipsometry, respectively.