%0 Journal Article
%A D.M Hwang
%A T.S Ravi
%A Ramamoorthy Ramesh
%A S.-W Chan
%A C.Y Chen
%A L Nazar
%A X.D Wu
%A A Inam
%A T Venkatesan
%B Applied Physics Letters
%D 1990
%G eng
%P 1690-1692
%R 10.1063/1.104138
%T Application of a near coincidence site lattice theory to the orientations of YBa2Cu3O7-x grains on (001) MgO substrates
%V 57
%X Various orientations of YBa2Cu3O7-x grains in polycrystalline films prepared on (001)MgO substrates by in situ laser deposition were determined using electron diffraction. Eight different types of in-plane orientations have been observed. These orientations agree well with the prediction of a simplified theory of near coincidence site lattice between YBa2Cu3O7-x and MgO. The YBa2Cu 3O7-x grains were found to have a high probability of forming low angle or low Σ boundaries among themselves. These grain boundaries are of low energy and should exhibit a high connectivity of Cu-O-Cu chains. Therefore, YBa2Cu3O7-x thin films on MgO can attain a Tc of ∼90 K and a Jc of ∼10 6 A/cm2 at 77 K.