A review of SiO2 etching studies in inductively coupled fluorocarbon plasmas

A comprehensive overview of results from mechanistic studies on plasma-surf ace interactions in inductively coupled fluorocarbon plasmas, which are cur rently widely used for the SiO2 etching process in semiconductor device man ufacturing industry, is presented. The plasma-surface interactions that are covered in this overview range from interactions at the plasma reactor wal l and coupling window, which affect the plasma gas phase, to interactions a t the substrate level, which determine the etching of both blanket surfaces and microscopic features. In particular, the effects of reactor wall tempe rature and parasitic capacitive coupling on the SiO2 etching process are ad dressed. Further, the mechanism of selective SiO2 to Si and Si3N4 etching o n blanket and inclined surfaces is discussed. Finally, it is shown how the SiO2 etch process in high aspect ratio microstructures differs from the etc h process on blanket surfaces. (C) 2001 The Electrochemical Society.