Growth, Microstructures, and Optoelectronic Properties of Epitaxial BaSn_1–xSb_xO_3−δ Thin Films by Chemical Solution Deposition

Epitaxial thin films of perovskite BaSn1–xSbxO3−δ are fabricated by a simple chemical solution deposition method, and the relationship among the processing, the microstructure, and the optoelectronic property is systematically investigated. The process of multiple annealing combined with the postannealing under nitrogen ambient is the optimal procedure to fabricate high quality BaSnO3−δ thin films. Sb doping in Sn sites facilitates the epitaxial growth of the BaSnO3−δ grains. The Hall results show that with increasing Sb doping content the carrier density and the carrier mobility are enhanced and decreased, respectively, resulting in the highest room-temperature electrical conductivity of 260 S/cm in the BaSn0.91Sb0.09O3−δ thin film. It is confirmed that the ionized Sb5+ and oxygen vacancies are the main scattering sources for carrier transport in BaSn1–xSbxO3−δ thin films. The results will provide guidance for synthesis of BaSnO3−δ-based and other donor-doped perovskite transparent conducting large-area thin films with low cost.