Ultrathin (1〜3Å) zirconium and silver film was inserted into the interface of Co/Cu artificial superlattices, and the effect on the magnetoresistance was investigated. As zirconium layer was inserted, the magnetoresistance decreased drastically and the antiferromagnetic coupling did not occur. In case of silver insertion, there is no significant change at the as-deposited state. After heat treatment, however, the antiferromagnetic coupling and the magnetoresistance ratio of silver inserted Co/Cu artificial superlattices increased more than twice. The increase of GMR is caused by the promotion of the composition profile at the interface of cobalt, which was confirmed by the ^<59>Co ferromagnetic resonance (FMR) analysis.
we have investigated the effects of process parameters (buffer layer material/substrate, Ar pressure, sputtering power, and thickness of Cu interlayer) on the MR (magnetoresistance) characteristics of NiFe/Cu/NiFe/FeMn spin valve structures. The effects of interface topology of spin valve multilayers on the shape of magnetoresistance curves have been discussed. The results suggest that the control of interface topology by process parameters is crucial for the improvement of MR characteristics.
Ultra thin layers of NiFeCo and NiFe were inserted at the interfaces of Ni and Cu to form a new multilayer structure. In case of NiFe inserting layer, magnetoresistance was about 6% and saturation magnetic field was 50 Oe. In case of NtFeCo inserting layer, magnetoresistance value increased to about 8% but the saturation magnetic field was also increased to about 150 Oe. Especially, the hysteresis in R-H (resistance-magnetic field) curve increased considerably, which deteriorate the dynamic response and the bias effect.