Independent gas feeds in a plasma reactor

摘要

A plasma etch reactor having independent gas feeds above the wafer and either at the sides or below the wafer. Preferably, a carrier gas such as argon is supplied from a showerhead electrode above the wafer while an etching gas is supplied from below. In the case of selectively etching an oxide over a non-oxide layer, the etchant gas should include one or more fluorocarbons.