Influence of Process Conditions of the Plasmochemical Etching of Polysilicon in a Cl2/Ar Mixture on Plasma Characteristics and Profile Evolution

A complex model of the plasmochemical etching of polysilicon in a Cl2/Ar mixture is proposed, based on a self-consistent description of volumetric (plasma parameters and composition) and heterogeneous (etching rate and shape) subsystems. The heterogeneous module has been optimized in terms of accounting for physico-chemical processes on the treated surface and ray tracing. The effects of the applied power and the initial composition of the mixture on the speed and shape of the etching profile at a given size of the mask opening area are investigated.