CONNECTION BETWEEN GIANT MAGNETORESISTANCE AND STRUCTURE IN MOLECULAR-BEAM EPITAXY AND SPUTTERED FE CR SUPERLATTICES/

We have performed a comparison of magnetoresistance and structure of e pitaxial and textured Fe/Cr superlattices grown by molecular-beam epit axy (MBE) and magnetron sputtering with either (110) and (100) orienta tions on a variety of substrates. MBE samples grown along the (100) or ientation, exhibit narrower rocking curves (mosaic spread) and lower s aturation resistivities than sputtered samples. On the other hand, (11 0) MBE and sputtered samples have comparable saturation resistivities. The magnetoresistance (Delta rho) of MBE and sputtered samples are co mparable. Epitaxial MBE samples, with small rocking curves, show a cle ar correlation between the magnetoresistance and rocking curve width. In sputtered samples, roughness, controlled by the deposition pressure , plays an important role although the general trends depend on orient ation and mosaic spread of the samples.