Characterization of off-axis sputtered La0.67Ca0.33MnO3 films and La0.67Ca0.33MnO3/YBa2Cu3O7-delta bilayers

Thin films of the colossal magnetoresistive material La0.67Ca0.33MnO3 (LCMO) have been grown by off-axis sputtering from a single target of the LCMO material onto various substrates and studied by electrical transport, x-ray diffraction, scanning electron microscopy and atomic force microscopy. The LCMO films typically grow with the (002) direction oriented normal to the film We find magnetoresistances at 6 T of approximate to 90%. We observe a scaling between the temperature of the resistivity peak (T-p) and the relative change in resistivity between room temperature and the resistance peak for T-p varying from 90 to 270 K. This scaling is consistent with an activated resistivity above the peak, with an activation temperature of approximate to 940 K. Films of LCMO grown on cubic zirconia exhibit an upturn in resistivity at low temperatures. Bilayers of LCMO and the superconductor YBa2Cu3O7-delta have been grown and compared to see the effects of having either the magnetic or superconducting layer first in the sequence.