Methods for selective deposition of doped semiconductor material

A selective deposition method comprising the steps of:

• providing a substrate, comprising a surface comprising a first area comprising a first material and a second area comprising a second material, within a reaction chamber;
• selectively and epitaxially depositing a first doped semiconductor layer overlying the first material;
• and
• selectively and epitaxially depositing a second doped semiconductor layer overlying the first doped semiconductor layer;
• wherein the first material comprises a doped or undoped monocrystalline material selected from the list consisting of silicon (Si), silicon germanium (SiGe), germanium tin (GeSn), silicon germanium tin (SiGeSn), and germanium (Ge);
• wherein the second material comprises a non-monocrystalline dielectric material selected from silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbide, and mixtures thereof;
• wherein the step of selectively depositing the first doped semiconductor layer comprises controlling a pressure of the reaction chamber to be less than 760 Torr;
• and
• wherein one or more of the step of selectively depositing the first doped semiconductor layer or the step of selectively depositing the second doped semiconductor layer comprises repeating a cycle comprising flowing one or more precursors to the reaction chamber and of flowing an etchant to the reaction chamber.