Device fabrication by plasma etching

Claim 1

Process for fabrication of an article comprising at least one operation during which the article undergoing fabrication comprises a surface of material to be etched wherein the said article is etched within a plasma environment contained within an apparatus, the plasma resulting from imposition of an electrical field across gaseous reactant between two electrodes, etching being primarily due to chemical reaction with the said material to be etched, the said gaseous reactant including an effective etchant precursor for yielding a plasma-derived effective etchant primarily responsible for the said chemical reaction and an unsaturate precursor which yields ethylenically unsaturated material or radical which may yield unsaturated material here designated as "unsaturate" which may combine with effective etchant to reduce the amount of available effective etchant, characterized in that the said gaseous reactant includes an oxidant precursor which yields an additional oxidant which combines with unsaturate to result in reduced reaction between unsaturate and effective etchant and thereby increase concentration of effective etchant whereby the rate of the said chemical reaction is increased.