| abstract |
The present invention is directed to the etching of a material selected from the group consisting of silicon dioxide, silicon nitride, boronphosphorus silicate glass, fluorosilicate glass, siliconoxynitride, tungsten, tungsten suicide and mixtures thereof under plasma etch conditions , particularly for cleaning operations to remove silicon dioxide or silicon nitride from the walls and other surfaces within a reaction chamber of a plasma-enhanced chemical vapor deposition reactor. The etching chemicals used in the etch process are trifluoroacetic acid and it derivatioves, such as; trifluoroacetic anhydride, trifluoromethyl ester of triflroroacetic acid and trifluoroacetic acid amide and mixrtures thereof. |