Method of plasma etching.

摘要

The present invention enhances silicon etching rate and improves the productivity of a silicon etching apparatus. In a vacuum chamber, plasma etching is performed. Chlorine gas is supplied at a rate of 250 ml/min or above, oxygen gas is added to the chlorine gas at 2.0% by volume or less relative to the chlorine gas. The workpiece is maintained at 0 DEG C or below or the stage mounted with the workpiece is maintained at -10 DEG C or below during etching. <IMAGE>