Abstract: In one embodiment, a method is proposed for etching a boron dope hardmask layer. The method includes flowing a process gas comprising at least CH4 into a processing chamber. Forming a plasma in the process chamber from the process gas and etching the boron doped hardmask layer in the presence of the plasma. In other embodiments, the process gas utilized to etch the boron doped hardmask layer includes CH4, Cl2, SF6 and O2.

Abstract: Methods for processing a substrate include (a) providing a substrate comprising a silicon germanium layer and a patterned mask layer atop the silicon germanium layer to define a feature in the silicon germanium layer; (b) exposing the substrate to a first plasma formed from a first process gas to etch a feature into the silicon germanium layer; (c) subsequently exposing the substrate to a second plasma formed from a second process gas to form an oxide layer on a sidewall and a bottom of the feature; (d) exposing the substrate to a third plasma formed from a third process gas to etch the oxide layer from the bottom of the feature; and (e) repeating (b)-(d) to form the feature in the first layer to a desired depth, wherein the first process gas, the second process gas and the third process gas are not the same.

Abstract: In one embodiment, a method is proposed for etching a boron dope hardmask layer. The method includes flowing a process gas comprising at least CH4 into a processing chamber. Forming a plasma in the process chamber from the process gas and etching the boron doped hardmask layer in the presence of the plasma. In other embodiments, the process gas utilized to etch the boron doped hardmask layer includes CH4, Cl2, SF6 and O2.