Fabrication Of (Hg,Re)-1212 Thin Films With Flat Surface On Various Substrates

Abstract

We improved the surface morphology of(Hg,Re)-1212 thin films on STO (100), LSAT(100) and LAO(100) substrates, and achieved a high value of the critical current density J c on STO substrates. A 100-nm-thick Re0.1Ba2CaCu2Oz precursor film with an HgO protective cap layer was deposited on each substrate by pulsed laser deposition and subsequently annealed under an appropriate Hg vapor pressure in an evacuated quartz tube. The thickness of the obtained films was about 75 nm. Large pinholes and outgrowths were not conspicuously observed on the surface, indicating that homogeneous epitaxial growth was realized by employing rather thin Re0.1Ba2CaCu2Oz precursor films. As-fabricated films exhibited T c (zero) of 109 — 117K. The J C values at 77 Kin a self-field were 1.0 × 107, 4.5 × 106 and 2.7 × 106 A/cm2 for STO, LSAT and LAO substrates, respectively.