Self-limiting etching method with multiple levels

摘要

The method involves forming (410) a protective mask i.e. hard mask (230), covering masked areas of a face of a substrate and defining an intermediate space. A plasma etching of relief patterns (110) is performed (420) in a chamber to form inclined flanks from the masked areas on the space by forming a continuous passivation layer (440) on the inclined flanks to produce auto limitation of the etching when the inclined flanks join each other. An additional gas to the plasma is introduced into the chamber, where the gas has molecules of a chemical species participating in formation of the layer.