Volatilization silicides

If the rules for volatiles and thermodynamics of the haUdes are followed, the reaction can be used for aluminizing, silicidizing, chromizing, and similar processing. 

The growing interest in volatile silyl-metal complexes for chemical vapor deposition reactions should also be mentioned. This technique is extremely useful for the preparation of silicide films in microelectronic devices. Further examples of applications of silicon-metal compounds are given in the appropriate sections. 

Carbide decompositions yield no volatile product and, therefore, many of the more convenient experimental techniques based on gas evolution or mass change cannot be applied. This is a probable reason for the relative lack of information about the kinetics of reaction of these and other compounds which are correctly classifed under this heading, such as borides, silicides, etc. 

Pt—Q—Salt, [Pt(NH3)2(HP04)] and [Pt(OH)6]2 (259,260). Chloride-based baths have been superseded by P-Salt-based baths, which are more stable and relatively easily prepared. Q-Salt baths offer even greater stability and produce hard, bright films of low porosity. Plating under alkaline conditions employs salts of [Pt(OH6)]2. These baths are easily regenerated but have low stability. Platinum films have uses in the electronics industry for circuit repair, mask repair, platinum silicide production, and interconnection fabrication (94). Vapor deposition of volatile platinum compounds such as [Pt(hfacac)2] and... 

After aluminum, the refractory metals and their silicides have been the subject of the most extensive efforts in metal etching (150-155). Because the fluorides and chlorides of the transition metals and silicon are volatile in the presence of ion bombardment, etch studies have been performed with nearly... 

These examples illustrate the important general point that the metal silicon ratio of the silicide film is always the same as that in the volatile precursor. 

Such a dependence is frequently observed experimentally in the oxida-tion of transition metals forming volatile oxides, and also of their alloys, carbides, nitrides, borides, silicides and other chemical compounds.350 365 An example taken from the work of E.A. Gulbransen and K.F. Andrew389 is presented in Fig. 5.22. 

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