Preparation of lanthanum zirconate films with a widely controllable La/Zr ratio by LCVD

Lanthanum zirconate (LZ) films with a controllable La/Zr composition were prepared by laser enhanced chemical vapor deposition (LCVD). The effects of different precursors ratio, i.e. the La(dpm)3/Zr(dpm)4 molar ratio, on composition, crystal structure, morphology and electrical conductivity of films were investigated. The formation region of columnar and purely cubic pyrochlore structured LZ films with a controllable La/Zr molar ratio in a wide range of 0.51-2.53 was mapped. Crystal structure changed with the different precursor's ratio, which was caused by atomic substitution between lanthanum and zirconium, being proved by combining with experimental and theoretical XRD patterns. It is found that electrical conductivity of non-stoichiometric LZ films is up to 4.3 × 10−3 S cm−1 at 1073 K. The columnar pyrochlore structured LZ films with a wide region of non-stoichiometric compositions are expected to be candidates for many potential applications, such as dielectric, thermal barrier coatings and nuclear waste treatment materials.