Magnetic properties and magnetoresistance (MR) are examined for the Fe/Au multilayers (MLs) prepared on glass substrates by electron-beam evaporation techniques as a function of the thicknesses of Fe and Au layers; dFe and dAu. For small dFe, the perpendicular magnetic anisotropy is induced, and in the films of dFe≈5 Å, the stripe magnetic domain patterns are observed. In dFe⩽3 Å, however, a superparamagnetic nature and a granular-type giant magnetoresistance (GMR) appear at room temperature. In a series of [Fe(3 Å)/Au(dAu)]40 MLs, the MR ratio increases with dAu and reaches the first peak at around 10 Å. On the other hand, at 14 K, the ferromagnetic component having a perpendicular anisotropy becomes dominant, and the GMR arises from the random wall alignment due to the antiferromagnetic coupling between the adjacent Fe layers, causing the first MR peak at dAu≈10 Å. The layered structure is obscured and the superparamagnetic Fe grains are created by annealing at 300–350 °C, followed by the crystalline growth upon annealing at temperatures above 350 °C. These variations in the film morphology cause the changes in the saturation magnetization and the MR ratio.

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Co-Au granular films have been prepared on glass substrates by rf sputtering. The magnetization curve exhibits the superparamagnetic and ferromagnetic natures. When the Co composition, x, decreases, the superparamagnetic nature increases, and the giant magnetoresistance (MR), which comes mainly from the superparamgnetic granules, increases up to about 2.5 % at x '" 23 at%. When the film is annealed, the granules grow keeping the superparamgnetic nature, and so the change in the resistivity, L!p, is held almost constant up to 250•C. The MR ratio increases on annealing and shows the maximum value of about 2.5% at 300•C. Annealing above 300•C causes the magnetism change from the superparamagnetic to the ferromagnetic due to the grain growth above the critical size, resulting in the decrease of L!fY. Furthermore, the growth of the ferromagnetic (Ill) oriented Co grains causes the increase in the perpendicular anisotropy.

Mo S 2 − x O x films were prepared on the rollers of a cross-roller bearing by the radio-frequency magnetron-sputtering method. Outgassing properties of these rollers at various temperatures were measured by the thermal-desorption method. For film with oxygen content of 2.8at.%, the unique gases of M∕e=32 (S+) and 34 (H2S+) were detected at about 370 and 420K, respectively. These gases were not detected until 500K after baking at 393K for 24h. In order to understand the outgassing mechanism of these gases, the chemical structure of film surface was analyzed by x-ray photoelectron spectroscopy before and after the thermal-desorption spectroscopy (TDS) measurement. An increase of MoO2 and a decrease of free sulfur in the film were confirmed after the TDS measurement. This result suggests that MoO2, S, and H2S are produced by the chemical reaction between adsorption water and MoS2. In addition, it has been found that the detection temperature and peak temperature of H2S become high with the increase in the oxygen content in the film.