Formation of highly-oriented and polycrystalline lanthanum nickelate films by a spin coating-pyrolysis process

LaNiO3 films were prepared by a spin coating-pyrolysis technique on various substrates using metal naphthenates as starting materials. By X-ray diffraction θ–2θ scan, highly oriented LaNiO3 films with smooth surface were prepared on SrTiO3(100) and LaAlO3(012) substrates, while the films on sapphire (0001) and polycrystalline Y2O3-doped ZrO2 exhibited random orientation. The highly-oriented LaNiO3 films on SrTiO3(100) and LaAlO3(012) showed a good metallic character. In this study, we conclude that lattice-mismatches between films and substrates used affect film properties such as crystallization, surface morphology and resistivity.