  We have investigated the influence of the superconducting layer thickness, d,
on the structural and transport properties of Co-doped BaFe2As2 films deposited
on Fe-buffered MgO substrates by pulsed laser deposition. The superconducting
transition temperature and the texture quality of Co-doped BaFe2As2 films
improve with increasing d due to a gradual relief of the tensile strain. For
d>90 nm an additional 110 textured component of Co-doped BaFe2As2 was observed,
which leads to an upward shift in the angular dependent critical current
density at H // c. These results indicate that the grain boundaries created by
the 110 textured component may contribute to the c-axis pinning.
