Highly sensitive giant magnetoresistance in NiFe/(Ni/Fe/Cu)/sub n//NiFe thin films

GMR of 0 to 6.95% has been found in fields of 0 to 50 Oe at room temperature in NiFe (5 nm)/[Ni(1.58 nm)/Fe(0.42 nm)/Cu(2.1 nm)]/sub 8//NiFe(7 nm) thin films prepared by DC magnetron sputtering with extremely precise thickness control. The full width at half maximum (FWHM) of the GMR curve was 10.4 Oe. The top and bottom NiFe layers had antiferromagnetic coupling to adjacent Ni/Fe layers across the Cu layers and also maintained magnetically soft characteristics. The NiFe/(Ni/Fe/Cu)/sub 8//NiFe sensor which was 40 nm thick, 3.5 /spl mu/m wide and 15 /spl mu/m long showed a large output 4 times as large as NiFe/Al/sub 2/O/sub 3//NiFe sensors.>