The Structure of BaTiO[sub 3] and BaTiO[sub 3]- YBa[sub 2]Cu[sub 3]O[sub 7-δ] Thin Films Studied by X-Ray Triple-Axis Diffraction.

The structures of BaTiO[sub 3] thin films and BaTiO[sub 3]/YBa[sub 2]Cu[sub 3]O[sub 7-δ] bilayer films grown on SrTiO[sub 3] and LaAlO[sub 3] substrates, respectively by pulsed laser deposition, have been investigated by X-ray triple-axis diffraction. The orientation, the interface mismatch and strain status, and the in-plane and perpendicular lattice constants of the epilayers have been determined by reciprocal space map analysis. The results show that both the lattice constants and the structural imperfections of the BaTiO[sub 3] layers are relevant to the oxygen partial pressure. The a[sub ⊥]/a... increases while the full width at half maximum (FWHM) of the rocking curves decreases with the decrease in the partial oxygen pressure. [ABSTRACT FROM AUTHOR]