Lam Research Corporation
Feedback Control System for Iterative Etch Process

Abstract:

An iterative etch process includes a plurality of cycles performed in a successive manner on a substrate. Each cycle of the plurality of cycles includes a deposition phase and an activation phase. The deposition phase is performed before the activation phase in each cycle. The deposition phase is defined as a plasma-based process to enable removal of a particular material from a surface of the substrate. The activation phase is defined as a plasma-based process to remove the particular material from the surface of the substrate. One or more feedback control signals are acquired during the iterative etch process, correlated to a condition of the substrate, and analyzed to determine the condition of the substrate. One or more process parameters of the iterative etch process is/are adjusted based on the condition of the substrate as determined by analyzing the one or more feedback control signals.