Co–Ni–Cu/Cu multilayers have been electrodeposited directly onto n-type Si substrates. This removes the need to use a seed-layer deposited by some other method as part of the growth process and makes electrodeposition a significantly more convenient method for fabricating films that exhibit giant magnetoresistance (GMR). A maximum GMR of over 10% and a sensitivity of over 0.04%/Oe were recorded. The GMR and sensitivity of the multilayers both increase with increasing Cu layer thickness.

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We consider the phenomenon of heterogeneous nucleation in electrolytic cells. Through the proposition of a stochastic model, we derive an equation to describe the migration of solute ions and their reaction near the electrode surface. Defining particular boundary conditions, the stochastic equation is solved and the time dependent probability density is related to the flux of ions towards the growing nucleus. The flux of ions is identified as the current transient expression, which is adequate for a comparison with the experimental results. The theory is powerful enough to reproduce results obtained by electrodepositing cobalt on n-type silicon and to explain deviations from predictions of the standard model for three-dimensional nucleation diffusion limited growth.

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We have studied the influence of amorphous and crystalline substrate materials, such as a-Si and a-Si:H, as well as c-Si(111), (100), and hydrogen implanted c-Si(111) on the outdiffusion of Si through an evaporated Au thin film, and its subsequent oxidation in atmosphere. Using Auger electron spectroscopy depth profiling we observed that the SiO2 layer thickness d formed on top of the Au film strongly depends on the type of substrate material giving most enhanced Si outdiffusion from amorphous ones. The metastable phase AuxSi is detected on both interfaces between the Au/Si and the SiO2/Au layers. A temperature independent ratio, dH/d ≊ 2, is observed for the oxide layer thickness of substrates with and without hydrogen. This is a surprising result, which indicates the influence of nonthermodynamic effects, probably related to the surface structure of the semiconductor substrates and a strong influence of hydrogen. A model of the layer structure is developed, which permits the calculation of diffusion activation energies resulting in qHD ≂ qD ≂ 1.0 (eV) for the diffusing species on substrates with and without hydrogen, respectively.