Etching method and computer-readable storage medium

Abstract

An etching method forms an opening with a substantially vertical profile extending to a stopper layer by performing an etching with a plasma of an etching gas acting on an object to be processed loaded in an evacuable processing vessel, wherein the object has a mask layer of a predetermined pattern, a silicon layer to be etched formed below the mask layer and the stopper layer formed below the silicon layer. The etching method includes a first etching process for forming an opening with a tapered wall surface in the silicon layer by using a first etching gas including a fluorine-containing gas and O2 but not HBr; and a second etching process for etching the opening by using a second etching gas including a fluorine-containing gas, O2 and HBr.

Dependencies are inferred from the claim text.