Electrical conductivity of epitaxial La0.6Sr0.4Co0.2Fe0.8O3−δ thin films grown by pulsed laser deposition

Abstract Epitaxial La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3− δ (LSCF) thin films have been grown successfully on single crystal LaAlO 3 substrate by pulsed laser deposition (PLD). AFM micrographs have shown a rms roughness of 5A for the 550 °C deposited films. The films further exhibited electrical conductivities of as high as 2.3 × 10 3  S cm −1 at 600 °C, with an activation energy of 0.09 eV. The surface exchange coefficient ( k c h e m ) of the epitaxial LSCF thin film, determined by electrical conductivity relaxation (ECR) technique, increased with the increasing temperature, and reached a value of ∼5.1 × 10 −6  S cm −1 at temperatures above 620 °C.