Abstract
The magnetic and magnetoresistive properties of films having spin valve structures were investigated. The basic structure of such films consists of two ferromagnetic layers separated by a Cu layer. One of the ferromagnetic layers is strongly biased by an NiO antiferromagnetic film in direct exchange contact with it. Spin valve films having an NiO/NiFe/Cu/NiFe structure show good sensitivity, and an MR ratio (Δρ/ρ) of 4% in an applied field of 10 Oe. Films with the layered structure NiO/NiFe/Cu/NiFe/Cu/NiFe/NiO show an MR ratio of 7% in a field of 10 Oe. On the other hand, NiO/NiFe/Co/Cu/Co/NiFe films show an MR ratio of 6% to 7.5%. The thermal stability of spin valve films was also studied.
