The surface topography of a real lotus leaf was successfully replicated using a capillarity directed soft lithographic technique. The replication was carried out on poly(methyl methacrylate) (PMMA) film coated on a silicon wafer. The friction property of the patterned surfaces was investigated on a microscale. Its friction coefficient was almost six times lower than that of the PMMA thin film. The reduced real area of contact projected by the patterned surface appears to be the main reason for its superior friction property.

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Top synthetic spin valves with structure Ta/NiFe/CoFe/Cu/CoFe( P1)/Ru/CoFe( P2)/FeMn/Ta on Si ͑100͒ substrate with natural oxide were prepared by dc magnetron sputtering system. We have changed only the thickness of the free layer and the thickness difference ( P1Ϫ P2) in the two ferromagnetic layers separated by Ru, and investigated the effect of magnetic film thickness on the interlayer coupling field in a spin valve with a synthetic antiferromagnet. As the free layer thickness decreased from 70 to 20 Å, the interlayer coupling field was increased due to the magnetostatic coupling ͑orange peel coupling͒. In the case of the thickness difference in the pinned layers, the interlayer coupling field agreed with the modified Néel model suggested in the top synthetic spin valve structures. However, in the case of t P1 ϭt P2 , and t P1 ϭt P2 ϩ5 Å, it was found that the interlayer coupling field could not be explained by the modified Néel model. The deviation of the modified Néel model at the dip zone could be due to the large canting of the pinned layers, which depend on applied field and different thickness in synthetic antiferromagnetic structure. The dependence of Cu thickness on the interlayer coupling field was investigated and 10 Oe of the interlayer coupling field was obtained when the Cu thickness is 32 Å.

In this study, the magnetic properties and microstructures have been investigated in Co–Ni–Fe–N soft magnetic thin films with various film thicknesses (0.01–1.0 μm). As the film thickness decreases, the coercivity, electrical resistivity, and magnetic anisotropy field of these films increases from 1.1 to 7.9 Oe, 53 to 188 μΩ cm, and 20 to 70 Oe, respectively. In addition, excellent high frequency characteristics were achieved in Co–Ni–Fe–N films with thicknesses less than 0.3 μm, where an effective permeability of, ∼1000 was maintained out to 700 MHz. Analysis results from XRD, TEM, and FMR show that a 0.1-μm-thick film is composed of an amorphous phase. This amorphous phase gradually changes to a crystalline phase with increasing film thickness.

As-deposited Fe–Co–Ta–N soft magnetic thin films with a thickness of 250 nm were fabricated to achieve high saturation magnetization and excellent high-frequency characteristics. During sputtering, the input power was fixed at 450 W and the nitrogen partial pressure varied from 0% to 10%. In these films, the values of saturation magnetization and coercivity that were obtained were 17–23 kG and 3–6 Oe, respectively. The Fe78Co8Ta9N5 (4% PN2) film exhibits excellent high-frequency characteristics with an effective permeability of about 2000, which is maintained up to 700 MHz. Also, this film has Bs=21 kG, Hc-hard=3 Oe, ρ=100 μΩ cm, and Hk=20 Oe. These high-frequency characteristics could result from the high values of the electrical resistivity and the magnetic anisotropy field. Furthermore, the corrosion resistance of these films was improved by the addition of nitrogen to give characteristics better than those of Co–Ni–Fe and Fe–Hf–N films.