Abstract: Embodiments of methods for forming features in a silicon containing layer of a substrate disposed on a substrate support are provided herein. In some embodiments, a method for forming features in a silicon containing layer of a substrate disposed on a substrate support in a processing volume of a process chamber includes: exposing the substrate to a first plasma formed from a first process gas while providing a bias power to the substrate support, wherein the first process gas comprises one or more of a chlorine-containing gas or a bromine containing gas; and exposing the substrate to a second plasma formed from a second process gas while no bias power is provided to the substrate support, wherein the second process gas comprises one or more of an oxygen-containing gas or nitrogen gas, and wherein a source power provided to form the first plasma and the second plasma is continuously provided.

Abstract: Embodiments of methods for etching a substrate include exposing the substrate to a first plasma formed from an inert gas; exposing the substrate to a second plasma formed from an oxygen-containing gas to form an oxide layer on a bottom and sides of a low aspect ratio feature and a high aspect ratio feature, wherein the oxide layer on the bottom of the low aspect ratio feature is thicker than on the bottom of the high aspect ratio feature; etching the oxide layer from the bottom of the low and high aspect ratio features with a third plasma to expose the bottom of the high aspect ratio feature while the bottom of the low aspect ratio feature remains covered; and exposing the substrate to a fourth plasma formed from a halogen-containing gas to etch the bottom of the low aspect ratio feature and the high aspect ratio feature.

Abstract: Embodiments of methods for forming features in a silicon containing layer of a substrate disposed on a substrate support are provided herein. In some embodiments, a method for forming features in a silicon containing layer of a substrate disposed on a substrate support in a processing volume of a process chamber includes: exposing the substrate to a first plasma formed from a first process gas while providing a bias power to the substrate support, wherein the first process gas comprises one or more of a chlorine-containing gas or a bromine containing gas; and exposing the substrate to a second plasma formed from a second process gas while no bias power is provided to the substrate support, wherein the second process gas comprises one or more of an oxygen-containing gas or nitrogen gas, and wherein a source power provided to form the first plasma and the second plasma is continuously provided.

Abstract: Embodiments of methods for etching a substrate include exposing the substrate to a first plasma formed from an inert gas; exposing the substrate to a second plasma formed from an oxygen-containing gas to form an oxide layer on a bottom and sides of a low aspect ratio feature and a high aspect ratio feature, wherein the oxide layer on the bottom of the low aspect ratio feature is thicker than on the bottom of the high aspect ratio feature; etching the oxide layer from the bottom of the low and high aspect ratio features with a third plasma to expose the bottom of the high aspect ratio feature while the bottom of the low aspect ratio feature remains covered; and exposing the substrate to a fourth plasma formed from a halogen-containing gas to etch the bottom of the low aspect ratio feature and the high aspect ratio feature.