Gold over silicon

Fig. 9. HREM images of metal particles over amorphous substrates a gold over silicon,b silver over carbon, c and d colloidal copper on different orientations showing twins and hexagonal packing. (All particles were observed under [110] zone axis. Taken from [28].)...

Titanium can be etched in fluorine-, chlorine-, or bromine-containing gases, because all the halides are volatile. Chlorides and bromides have been studied to a great extent since they result in high selectivity over silicon- containing films, and do not promote staining on gold (77). 

The discussed models of the carbon nanofilaments and nanotubes forma tion allow many other thermodynamic factors to be taken into consider ation, all of which affect the shape, texture, and growth rate of the nano objects under discussion (see, e.g.. Refs. [6, 7]). It is assumed that the forma tion of the fluidized active component of the catalyst nanoparticles due to its stationary oversaturation with the crystallizing component gives rise to the possibility to synthesize nanofilaments and nanotubes from not only carbon but also from different substances, such as silicon carbide (over catalysts capable of dissolving carbon and silicon simultaneously), germanium metal (over gold metal catalysts [8]), and so on. 

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