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arXiv · 1805.10861

Interdiffusion study in group IVB, VB and VIB refractory metal-silicon systems

Soumitra Roy
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Abstract

The solid state interdiffusion in refractory metals and single crystal Si are studied in details by diffusion couple technique. The wide range of application and importance of silicides in various devices are the motivation for these studies. The refractory metals which are considered and compared in these M/Si systems (M = metal) are group IVB elements Ti, Zr and Hf, group VB elements V, Nb and Ta, group VIB elements Cr, Mo and W. Out of these systems, the Ti, Zr, Hf, Ta and W M-Si systems have been studied in this thesis. The results of V, Nb and Mo systems, which were studied before in our group, are compared with the result of present study and a systematic pattern in diffusion behavior is found with increasing atomic number of the elements, group-wise in the periodic table. These studies help to understand the growth kinetics of the phases formed, diffusion parameters, relative mobilities of the species and presence and behavior of the different defects in the crystal structure. The different diffusion parameters calculated in present study are, parabolic growth constants, integrated diffusion coefficients, activation energy for diffusion, ratio of tracer diffusivities and tracer diffusivity of the species

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Soumitra Roy. 2018-05-28. Interdiffusion study in group IVB, VB and VIB refractory metal-silicon systems. https://arxiv.org/abs/1805.10861

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