Electrostatic Spray Deposition of Perovskite-Type Oxides Thin Films with Porous Microstructure

Abstract

The deposition of perovskite-type oxides thin films [La_0.8Sr_0.2MnO₃ and La_1−xSr_xCo_1−yFe_yO₃ (0 ≦ x ≦ 0.4 and 0 ≦ y ≦ 1)] was investigated using the electrostatic spray deposition (ESD) technique. Lanthanum nitrate, strontium chloride and manganese nitrate, or cobalt nitrate and iron nitrate were dissolved into a mixture of 33 vol% ethanol and 67 vol% butyl carbitol, which was used as precursor solution. The effect of process parameters, such as deposition temperature, deposition time and concentration of precursor solution, on the surface morphology and microstructure of thin films were examined with scanning electron microscope (SEM). The deposited La_0.8Sr_0.2MnO₃ and La_1−xSr_xCo_1−yFe_yO₃ thin films were amorphous at the used deposition temperature (573K). Subsequently, the samples were heated at 1173 K for 2 h and were studied using X-ray diffraction (XRD). As the result, the crystal structure of the samples transformed to the desired perovskite phase. The chemical analysis of the thin films was investigated using energy dispersion X-ray (EDX) analysis. The observed chemical compositions of the samples were in a fair agreement with the ones of the starting solutions.