• Journal of the Korean Electrochemical Society
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• v.8 no.3
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• pp.125-129
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• 2005

We have investigated the electrochemical factors affecting the magnetic properties of hard magnetic CoP nanowires and soft magnetic CoFe nanowires fabricated by ac electrodeposition into self-made AAO(anodic aluminum oxide) nano-templates. AAO template having nano scale pores of high aspect ratio has been prepared through 2-step anodizing of aluminum foil in sulfuric acid. Hard Magnetic properties of CoP nanowires were highly conditional on the applied ac potential which could be a decisive factor to make CoP nanowires made up of either pure hcp crystals or a mixture of hop crystals and fcc crystals. On the contrary to CoFe films, there was no anomalous codeposition in the electrodeposition of soft magnetic CoFe nanowires which exhibited their best saturation magnetization of 238 emu/g at the composition of $Co_{30}Fe_{70}$.

• Korean Journal of Materials Research
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• v.4 no.1
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• pp.107-112
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• 1994

The phase transition and the surface and interface morphologies of $TiSi_2$ formed on atomically clean Si substrates are investigated. 200$\AA$ Ti and 400$\AA$ Si films on Si(ll1) have been codeposited at elevated temperatures (400~$800^{\circ}C$) in ultrahigh vacuum. The phase transition of TiSiL is characterized with using XRD. The results distinguish the formation of the C49 and C54 crystalline titanium silicides. The surface and interface morphologies of titanium silicides have been examined with SEM and TEM. A relatively smootb surface is observed for the C49 phase while a rough surface and interface are observed for C54 phase. The islanding of the C54 phase becomes severe at high temperature ($800^{\circ}C$). Islands of TiSiL have been observed at temperatures above $700^{\circ}C$ but no islands are observed at temperatures below $600^{\circ}C$. For films deposited at $400^{\circ}C$ and 500%. weak XRD peaks corresponding to TiSi were observed and TEM micrographs exhibited small crystalline regions of titanium silicide at the interface.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.125-130
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• 2002

An attempt was made for the application of porous reticular metal to a heat dissipation material in semiconductor process. For this aim, the electrodeposition of Fe/Ni alloy on the porous reticular Cu has been performed to minimize the thermal expansion mismatch between Cu skeleton and electronic chip. Preliminary tests for the electrodeposition of Fe/Ni alloy layer were conducted by using standard Hull Cell to examine the effect of current density on the composition of alloy layer. It seemed that mass transfer affected significantly the composition of Fe/Ni layer due to anomalous codeposition in the electrodeposition of Fe/Ni alloy. A paddle type stirring bath, which was employed to control the mass transfer of electrolyte in the work, was found to allow the electrodeposition Fe/Ni with a precise composition. result showed that the thermal expansion of Fe/Ni alloy layer was much lower than that of pure copper. From the tests of heat dissipation by using the apparatus designed in the work the heat dissipation material fabricated in the work showed the excellent heat dissipation capacity, namely, more than two times as compared to that of pure copper plate.