Alkoxide route to La0.5Sr0.5CoO3 epitaxial thin films on SrTiO3 |
| |
Authors: | Gunnar Westin Mikael Ottoson Annika Pohl |
| |
Affiliation: | aDepartment of Materials Chemistry, Ångström Laboratory, Uppsala University, Uppsala, Sweden |
| |
Abstract: | An all alkoxide based sol–gel route was investigated for preparation of epitaxial La0.5Sr0.5CoO3 (LSCO) films on 100 SrTiO3 (STO) substrates. Films with 20–30 to 80–100 nm thickness were prepared by spin-coating 0.2–0.6 M (metal) solutions on the STO substrates and heat treatment to 800 °C at 2 °C min? 1, 30 min, in air. The films were epitaxial with a cube-on-cube alignment and the LSCO cell was strained to match the STO substrate of 3.905 Å closely; a and b = 3.894 Å and 3.897 Å for the 20–30 and 80–100 nm films, respectively. The c-axis was compressed to 3.789 Å and 3.782 Å for the 20–30 and 80–100 nm films, respectively, which resulted in an almost unchanged cell volume as compared to polycrystalline film and nano-phase powders prepared in the same way. The SEM study showed mainly very smooth, featureless surfaces, but also some defects. A film prepared in the same way on an -Al2O3 substrate was dense and polycrystalline with crystallite sizes in the range 10–50 nm and gave cubic cell dimensions of ac = 3.825 Å. The conductivity of the ca 30–40 nm thick polycrystalline film was 1.7 mΩcm, while the epitaxial 80–100 nm film had a conductivity of around 1.9 mΩcm. |
| |
Keywords: | LaSeCoO Perovskite Epitaxial growth Sol-gel processing X-ray diffraction Structural properties |
本文献已被 ScienceDirect 等数据库收录! |
|