A unified semi-global surface reaction model of polymer deposition and SiO2 etching in fluorocarbon plasma

Abstract

We propose a semi-global surface reaction model to capture simultaneous polymer deposition and oxide etching in fluorocarbon plasma. The critical parameters of this model within reasonable ranges can be determined using predesigned experimental data with plasma diagnostics in inductively coupled fluorocarbon plasma. This model can describe the transition behavior from polymer deposition to oxide etch self-consistently without ad-hoc assumptions, providing better insight into abnormal etching behaviors in high aspect ratio contact hole etching, such as sidewall bowing and twisting toward next generation of memory devices in semiconductor industries.