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The effect of film thickness on magnetic properties of Cu80Co20 granular alloy was studied. It was observed that the susceptibility peak temperature, TM, strongly increases with the film thickness, t, for t

We have studied the magnetotransport and magnetic properties of a metallic granular FexAg100−x system, fabricated by using a magnetron cosputtering technique. Giant magnetoresistance was observed in a narrow range between x=10 and 25 vol %. Both the Fe volume fraction and the sample orientation significantly influence the magnetoresistance. This granular system also demonstrates some unique features as compared to multilayer systems.

Tunneling properties were studied on nanofabricated metal ferric tunnel structures on phosphorus doped silicon by measuring I-V characteristics and differential conductance versus bias over a wide temperature range. These properties were found to have weak temperature dependences up to 250K, unambiguously showing tunneling characteristics from metal ferric nanolines into Si via AlOx insulating barrier. Direct correlation was observed between thermal activation of deep levels in bulk Si and metal-semiconductor tunneling, revealing feasible mechanisms influencing the interfacial transport.

Studying annealed, magnetron sputtered, granular Cu80Co20 thin films revealed an anomalous magnetic particle size distribution in films annealed above 300°C. The measured magnetic susceptibility (χ-T) curves show a distinct double-peak structure, indicating the coexistence of two particle sizes. The emergence of a second peak around 250–300K was accompanied by an overall reduction in magnetization; this peak subsequently grew with annealing temperature coupled with magnetization recovery. These features, observed over a wide range of thicknesses (40–200nm), result from decomposition of Co nanoparticles around 300°C, followed by the growth of larger particles.