YBa2Cu3O7-y and YbBa2Cu3O7-y superconducting films prepared by chemical solution deposition on SrTiO3(001) substrate

Thin superconducting films of YBa2Cu3O7-y (Y123) and YbBa2Cu3O7-y (Yb123) h ave been derived from metal naphthenates gels spin-coated on SrTiO3 (0 0 1) substrates. X-ray diffraction and transmission electron microscopy (TEM) s how that the Yb123 film with its c-axis perpendicular to the substrate surf ace was epitaxially grown; while a mixture of c- and a-axis Y123 was derive d on the SrTiO3 (0 0 1) substrate. High-resolution electron microscopy furt her reveals that the c-axis Y123 thin film was epitaxially formed, covering the substrate surface. The 90 degrees oriented a- and c-axis Y123 componen ts are found to form meandering grain boundaries. (C) 2001 Elsevier Science B.V. All rights reserved.