In situ reflection high-energy electron diffraction observation of epitaxial LaNiO3 thin films

Abstract

Epitaxial LaNiO 3 (LNO) thin films were grown on (001) SrTiO 3 substrates by laser molecular-beam epitaxy. The growth process of the LNO films was monitored by in situreflection high-energy electron diffraction(RHEED). Clear RHEEDpatterns and the intensity oscillation of RHEED were observed during the epitaxialgrowth process. The morphology of the films was studied by atomic force microscopy. The results show that the filmsgrown by this method have a nanoscale smooth surface with the root-mean-square surface roughness smaller than 7 nm on an area of 1×1 μm 2 . X-ray diffractionpatterns indicate that the crystalline LNO films exhibited preferred (00l) orientation. The resistivity of the thin film is 0.28 mΩ cm at 278 K and 0.06 mΩ cm at 80 K, respectively.