HREM STUDY OF SPIN VALVES WITH MNNI PINNING LAYER

Four NiFe/Co/Cu/Co/NiFe/MnNi spin valves (SVs) with two different grow th configurations have been investigated by conventional and high reso lution electron microscopy (CTEM and HREM), Structures with the MnNi p inning layer above and below the ferromagnetic sandwich in both as-gro wn and annealed states have been studied, A correlation between their magnetic properties and their microstructure has been found. For each of these configurations, the structure of the MnNi pinning film is dif ferent and as a result, the exchange field (H-ex) value changes. In ad dition, the coercivity (H-c) of the sense layer seems to be related to its grain size and crystallographic texture.