The analysis of the time evolution of W spots deposited from WF6+H2 mixtures by an Ar+ laser reveals that at different partial pressure ratios different chemical pathways are preferred. For high p(H2)/P(WF6) ratios the rate limiting step is hydrogen desorption from the tungsten surface with an activation energy of 30-33 kcal/mol resulting in well-defined droplet-like patterns, while at low partial pressure ratios the formation of flat cone-like spots is preferred as a consequence of surface reactions of significantly lower activation energies (18-22 kcal/mol).
|Number of pages||4|
|Journal||Spectrochimica Acta Part A: Molecular Spectroscopy|
|Publication status||Published - 1990|
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