DIRECTIONAL SIO_2 ETCH USING PLASMA PRE-TREATMENT AND HIGH-TEMPERATURE ETCHANT DEPOSITION

摘要

Methods for processing a substrate are described herein. The methods include: disposing a substrate having an exposed surface comprising a silicon oxide layer in a processing chamber; Biasing the substrate; Treating the substrate to roughen a portion of the silicon oxide layer; Heating the substrate to a first temperature; Exposing the exposed surface of the substrate to ammonium fluoride to form one or more volatile products while maintaining a first temperature; And heating the substrate to a second temperature that is higher than the first temperature to sublime the volatile products.