• Journal of the Korean institute of surface engineering
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• v.23 no.1
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• pp.27-33
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• 1990

Thermodynamic analysis on silicon consumpton during the chemical vapor deposition of tungten was carried out by calculation equilibrium concerations of all possible product species utilizing a computer progrom according to VCS.(Villars-Cruise-Smith) algorithm. The calculation could show various reaction paths which dominate the tungsten deposition under different process conditions. According to the calculation, the consumption of silicon can also be reduced at a lower total pressure SiH4 without H2 as the reacting gas is most effective for suppression of the excessive consumption of silicon during the deposition process.

• Journal of the Korean Vacuum Society
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• v.8 no.3A
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• pp.181-186
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• 1999

The diffusion of oxygen atoms on tungsten (110) surface is studied by comparison of experiment results and recent calculations. It has been suggested that the thermodynamic factor which is inversely proportional to be compressibility has strong temperature dependence which may cause non-Arrhenius behavior of diffusion coefficient. Recent experiments, however, indicate effectively no temperature dependence of this factor and support the view that non-Arrhenius behavior originates from the dynamic factor rather than the thermodynamic factor. Discrepancies in coverage dependence of physical quantities between theory and experiment are discussed.

• Journal of the Korean institute of surface engineering
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• v.21 no.4
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• pp.176-182
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• 1988

Effects of Cr, Ni and W on the anodic polarization behavior were investigated for Fe-Cr-Ni-W alloys in deaerated 1N HCI solution. Surface films formed on the polarization were analysed using AES, SEM and EDAX. A higerconcentration of tungten was found in the surface oxide film compared to the matrix. It played an importanet role on incresing the stability of the passive film. The presence of an adequate amount of Cr was essential to increase the pitting resistance of the alloys in acid chloride media. Under 12 wt%cr,alloys containing 6wt%W did not exhidit any passivity at all. The main role of Ni was to control the microstructure rather than to modify the corrosion resistance. In 23 cr-14Ni-^W alloy, the duplex microstructure of ferrite($\delta$-phase) in an austenic matrix was developed. The reson why proferred pitting appeared in austenite and ferrite/austenite interface was that ferrite had more amount of Cr and W than austenite.