Structural and Electrical Properties of the YSZ/STO/YSZ Heterostructure.

The heterostructure thin films of yttria-stabilized zirconia (YSZ)/strontium titanate (STO)/YSZ with various thicknesses were deposited on MgO single crystal substrate by pulsed laser deposition (PLD) method. The structural and electrical properties of the YSZ/STO/YSZ heterostructure were studied through X-ray diffraction (XRD) and electrical conductivity measurements. The in-plane conductivities of the thin films were measured and compared with that of the bulk sample. The highest conductivities were reported for those samples with the thinnest YSZ (220) layers. The observed enhancement in the lateral ionic conductivity was probably caused by the combination of the misfit dislocation density and elastic strain in the interfaces. The enhanced ionic mobility was discussed in terms of the disorder introduced in the oxygen sublattice through the epitaxial strain at the interfaces. [ABSTRACT FROM AUTHOR]