Plasma etching method, semiconductor device manufacturing method and computer-readable storage medium

Abstract

There is provided a plasma etching method for forming a hole in a silicon oxide film formed on an etching stopper layer. The plasma etching method includes a main etching process for etching the silicon oxide film; and an etching process that is performed when at least a part of the etching stopper layer is exposed after the main etching process. The etching process includes a first etching process using a gaseous mixture of a CFgas, an Ar gas and an Ogas as the processing gas; and a second etching process using a gaseous mixture of a CFgas, an Ar gas and an Ogas or a gaseous mixture of a CFgas, an Ar gas and an Ogas as the processing gas. The first etching process and the second etching process are alternately performed plural times.