Study of epitaxial platinum thin films grown by metalorganic chemical vapor deposition

The metalorganic chemical vapor deposition technique has been successfully applied to the growth of epitaxial platinum thin films on (100) surfaces of single-crystal potassium tantalate (KTaO3) and strontium titanate (SrTiO3). Platinum thin films grown on KTaO3 (100) at a rate of 70 nm/h showed strong Rutherford backscattering spectroscopy (RBS)/channeling effects with a χmin of 4%. In-plane φ and θ-2θ scan x-ray diffraction analysis demonstrated the three-dimensional epitaxial alignment of the platinum film with the KTaO3 substrate. Transmission electron micrographs viewed in cross section provided additional information regarding the nature of the epitaxial Pt-KTaO3 interface. The room-temperature resistivity of a 60-nm-thick Pt film on KTaO3 (100) was 12.0 μΩ cm. X-ray diffraction and pole-figure analysis showed that in the case of Pt films deposited on either fused quartz or Si (100) surfaces, the resulting films were polycrystalline and were fully textured with <111≳ orientations perpendicular to the substrate surfaces.