Wet Etch Recipe Optimization for Enabling RMG Multi Vt Scheme

Abstract

Three chemistries are compared on metal oxide films to facilitate a stable and repeatable wet etching process to be used in the replacement metal gate module for multi-Vt for 2nm Gate All Around (GAA) Nanosheet. The etching recipes with the selected chemistry are optimized to improve within wafer (WiW) and wafer to wafer (WtW) uniformity using various chemical nozzle dispense options.