Optical transmission and carrier transport of epitaxial (001)- and (111)-oriented Ba0.96La0.04SnO3 thin films

Crystal phases growth with corresponding preferential orientations plays a key role in determining functional characteristics of thin films. Here, a detailed comparison study on optical transmission and carrier transport of Ba0.96La0.04SnO3 (BLSO) films which was fabricated on (001) and (111)-oriented SrTiO3 substrate were reported. Two kinds of films all show a high optical transmittance (similar to 82.5%) in the visible region. However, the optical transmittance of (001)-oriented film depends strongly on film thickness while the (111)-oriented film shows independence of film thickness. Although their electronic transports display a typical metallic behavior, the actual resistivity of (111)-film is two times larger than that of (001)-film. Based on the density functional calculation, we find that the charge distributions of Sn and 0 are much more denser on (001)-plane than (111)plane, indicating that (001)-plane not only has a larger carrier concentration but also the electrons transport more easily on it, A phenomenological model was also applied to quantify the resistivity ration rho(111)/rho(001) = 1.7, basically comparable to the experimental value of 2.5. Our results will offer experimental basis and theoretical reference for the design and application of perovskite BLSO transparent conducting films.