MECHANISM FOR UNIFORM ETCHING BY MINIMIZING EFFECTS OF ETCH RATE LOADING

摘要

A method for etching a layer stack structure on a substrate is provided. The method includes a step of etching the layer stack to a predefined stopping point using a reverse etch rate loading inducing chemistry. The method also includes a step of etching said layer stack through a target layer in the layer stack structure using a natural etch rate loading chemistry.