J. Auge1, Margit Jansen1, Hartmut G. Roskos1, H. Kurz1
1Institut für Halbleitertechnik II, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Sommerfeldstrasse 24, 52056 Aachen, Germany
Tóm tắt
We demonstrate that the surface morphology of 20–200-nm-thick magnetron-sputtered Y1Ba2Cu3O7 films can be optimized by careful control of the plasma current. The optimization can be performed at different substrate temperatures allowing us to maximize the transition temperature Tc and the homogeneity of the films independently from the optimization of the surface morphology. This sequence allows us to retain the characteristic high Tc values (Tc≳90 K, Jc≳106 A/cm2 at 77 K). To obtain very thin films (<40 nm) with similar superconducting properties, the deposition temperature has to be ramped during the sputter process.
