Vapour deposition of tungsten - control of fluorine content of tungsten vapours

摘要

Vapour deposited tungsten coatings, which for optimum quality and performance must contain only 5-25 ppm F2 are produced by controlling the amount of free F2 in the conventional vapour depositing gas mixt. of H2 and tungsten hexafluoride by addition of a small amount of inert carrier gas e.g. Helium saturated with water vapour by passage through a water bath. Tungsten deposites free from blisters or grain growth are produced.