Magnetotransport in manganite trilayer junctions grown by 90° off-axis sputtering

We report magnetotransport studies on La0.67Sr0.33MnO3/SrTiO3/La 0.67Sr0.33MnO3 trilayer junctions, fabricated using 90° off-axis sputtering. Films were grown on both (001) (LaAlO3)0.3-(Sr2AlTaO6)O 0.7 and (110) NdGaO3 substrates. The sputtered trilayers show improved junction resistance uniformity over those made using pulsed laser deposition. Cross-sectional transmission electron microscopy and atomic force microscopy studies confirm smooth interfaces and a uniform barrier. Magnetoresistances up to ∼100% are observed for junctions on (001) (LaAlO3)0.3-(Sr2AlTaO6) 0.7 with a 30 Å barrier at 13 K and around 100 Oe. Junction magnetoresistance versus magnetic field behavior is more stable, indicating improved transport and magnetic homogeneity across the junction. © 2001 American Institute of Physics.