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Co90Fe10/Cu/Co90Fe10/Ir25Mn75 spin-valves with a Ta seed layer were prepared by ion beam sputtering. Improvements in magnetoresistive (MR) and magnetic properties were obtained by adding H2 to Xe sputtering gas. Specifically, the coercivity in the free Co90Fe10 layer considerably decreased as the H2 flow rate was increased. Furthermore, exchange coupling between the Ir25Mn75 and pinned Co90Fe10 layers became stronger in the preparation under the higher H2 flow rate. X-ray diffraction, transmission electron microscopy, and secondary ion mass spectroscopy observations suggest that micro-crystallization of each layer is responsible for improving the MR and magnetic properties.

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CogoFelO/Cu/C09QFelO!Ir25Mn75 spin-valves with Ta buffer layer were prepared by ion beam sputtering. hnprovements in physical properties were obtained by adding H2 to Xe sputtering gas. Specifically, coercivity in the CoFe free layer considerably decreased with increasing H2-flow rate. In addition, exchange coupling between the IrMn and pinned CoFe layers became stronger in the preparation under the higher H2flow rate. X-ray diffraction, transmission electron microscope, and secondary ion mass spectroscopy observations suggest that micro-crystallization of each layer is responsible for improving the physical properties.

By inserting only 0.75 nm-thick Cu undedayer between the IrMn/CoFe/Cu/CoFe spin-valve stack and Ta underlayer, the MR ratio was about 1.8 times as large as that without the Cu layer. XRD and magnetic measurements suggest that the Cu "islands" formed in the initial growth stage modify the interfaces of the spin-Valve, resulting in the enhancement of the spin-dependent scattering. When the Cu thickness (t) was larger than 1.5 nm, the MR ratio and coercivity of the free layer were increased and decreased, respectively, in comparison with those of t=O nm. This was due to the considerable increase in the crystallinity of the spin-valve films. Namely, Cu is expected to function as the buffer "layer" in this thickness range. The inductive/spin-valve composite heads using a material developed in this study were stable and quiet in the dynamic performance.