Semiconductor structure and related methods

A method of fabricating a semiconductor device, comprising:

• forming a stack including a first silicon germanium (SiGe) layer and a second SiGe layer;
• forming a first silicon (Si) layer interposing the first and second SiGe layers;
• etching a first region of the stack, wherein etching the first region includes removing portions of each of the first Si layer, the first SiGe layer, and second SiGe layer to provide an opening having a first sidewall including the first SiGe layer, the first Si layer and the second Si layer;
• performing a passivation process on the first sidewall to form a passivated sidewall;
• and
• epitaxially growing a silicon layer on the passivated sidewall.

A method, comprising:

• growing an epitaxial stack of alternating silicon and silicon germanium layers on a substrate;
• etching an opening in the epitaxial stack exposing a surface of the substrate;
• introducing hydrochloric acid (HCl) to the substrate having the etched opening;
• and
• after introducing the HCl, growing a first portion of a silicon epitaxial material in the opening at a first temperature and growing a second portion of the silicon epitaxial material over the first portion at a second temperature greater than the first temperature.