Spin valves with NiO pinning layer

We have studied both top and bottom spin valves with NiO as an antiferromagnetic pinning layer. The largest bias fields of up to /spl sim/130 Oe were seen for NiFe/Cu/NiFe/NiO top spin valves. Larger bias fields appear to be correlated with partially (200)-textured NiO. The NiFe/Cu/NiFe/NiO samples exhibited GMR values in the 3-4% range. Larger GMR values were seen in NiO/Co/Cu/Co and Co/Cu/Co/NiO spin valves; the largest GMR observed was 11.3% for a bottom spin valve sample of this type.