Synthesis and characterization of dense Gd 2 Ti 2 O 7 pyrochlore thin films deposited using RF magnetron sputtering

Abstract Thin films of phase-pure pyrochlore Gd 2 Ti 2 O 7 have been synthesized by RF magnetron sputtering. The films were prepared from oxide targets in 50%O 2 /Ar atmosphere and deposited on 111 yttria-stabilized zirconia (YSZ) substrates at a temperature of 800 °C. The pyrochlore structure was confirmed via grazing angle X-ray diffraction and selected area electron diffraction (SAED). Transmission electron microscopy (TEM) analysis also showed that the films were dense and of uniform thickness with surface roughness of approximately 8 nm. The total conductivity measured with AC impedance spectroscopy was found to be independent of thickness and comparable in magnitude to that of bulk Gd 2 Ti 2 O 7 . Differences were observed in the Arrhenius behavior between the bulk and thin film samples and are attributed to varying states of order in the crystalline lattice compounded by different levels of background impurities.