CHEMICALLY ASSISTED ION-BEAM ETCHING OF SILICON AND SILICON DIOXIDE USING SF6

A chemical flux of sulfur hexafluoride (SF6) in conjunction with low-e nergy Ar-ion bombardment has been used for chemically assisted inn bea m etching (CAIBE) of silicon and silicon dioxide. The study has shown a large degree of independent control over the selectivity and anisotr opy in dry etching. The total etch rate could be controlled by varying either the Ar-ion milling parameters or the chemical flux of SF6. Etc h rate enhancement of 7-8 for silicon and 3-4 for silicon dioxide have been obtained over pure physical etching.