%0 Journal Article
%A D.M Hwang
%A Ramamoorthy Ramesh
%A C.Y Chen
%A X.D Wu
%A A Inam
%A M.S Hegde
%A B Wilkens
%A C.C Chang
%A L Nazar
%A T Venkatesan
%A S Miura
%A S Matsubara
%A Y Miyasaka
%A N Shohata
%B Journal of Applied Physics
%D 1990
%G eng
%P 1772-1776
%R 10.1063/1.346607
%T Epitaxial relations between in situ superconducting YBa2Cu 3O7-x thin films and BaTiO3/MgAl 2O4/Si substrates
%V 68
%X In situ superconducting YBa2Cu3O7-x films with Tc0 up to 87 K and Jc, 77 K up to 6×10 4 A/cm2 were prepared on Si substrates with MgAl 2O4 and BaTiO3 double-buffer layers. The epitaxial relations between various layers were established by transmission electron microscopy. The MgAl2O4 layer is heavily faulted. The subsequent BaTiO3 layer stops most of the faults, provides a template for the YBa2Cu3O7-x growth, and partially screens off the stress due to different thermal expansion coefficients. The microstructure of the YBa2Cu3O 7-x layer is very similar to that of the films deposited directly on SrTiO3, exhibiting a homogeneous heavily faulted single-crystal-like structure free from secondary phases and grain boundaries. The slight degradation of the transport properties is attributed to residual thermal stress.