Synthesis of Conductive LaNiO3 Thin Films by Chemical Solution Deposition

Metallic conductive LaNiO3 thin films have been prepared by the chemical solution deposition method. A homogeneous and stable LaNiO3 precursor solution was prepared by controlling the reaction of metal organics. Dehydration of the starting material Ni(acac)2·2H2O was a key factor in preparing a proper LaNiO3 precursor solution, because the hydrolysis of La(OiPr)3 has to be suppressed through the removal of hydrated water. The precursor films were prepared from the solution by dip-coating and spin-coating. 110-oriented LaNiO3 thin films were synthesized from the LaNiO3 precursor solution on fused silica substrates at 700°C. LaNiO3 film prepared by spin-coating had a better surface smoothness than that prepared by dip-coating. The resistivities of 100-nm-thick LaNiO3 films prepared by dip-coating and spin-coating were 3.8×10-5 Ω m and 2.9×10-5 Ω m, respectively, at room temperature.