As-deposited superconducting thin films (∼0.1 μm) of YBa 2Cu3O7-x have been prepared by pulsed laser deposition on (100) Si with buffer layers of BaTiO3/MgAl 2O4. X-ray diffraction studies reveal that the films grow epitaxially with the c axis preferentially oriented normal to the substrate surface. This is confirmed by ion channeling measurements along the (100) (normal to the surface) and (110) directions of the Si substrate showing a minimum yield of 54% along the (100), and 78% along the (110) axes using 2.8 MeV He++. Preliminary transmission electron microscopy study also supports these results. The as-deposited films have zero resistance temperatures of 86-87 K, and critical current densities of 6×10 4 A/cm2 at 77 K and 1.2×105 A/cm 2 at 73 K. Our results indicate that the superconducting properties of the films are limited primarily by the quality and degree of epitaxal growth of the buffer layers on the silicon substrate.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)