Methods of forming a layer comprising epitaxial silicon, and methods of forming field effect transistors

A method of forming a layer comprising epitaxial silicon, comprising:

• providing an opening within a first material received over a monocrystalline material;
• lining opposing sidewalls of the opening with a second material by deposition of the second material over the first material and to within the opening over the monocrystalline material, followed by anisotropic etching of the second material effective to expose the monocrystalline material;
• epitaxially growing a silicon-comprising layer from the exposed monocrystalline material within the second material-lined opening;
• and
• after the growing, in situ etching at least a portion of the second material lining selectively relative to the first material.

A method of forming a layer comprising epitaxial silicon, comprising:

• providing an opening within a first material received over a monocrystalline material;
• lining opposing sidewalls of the opening with a second material, monocrystalline material being exposed at a base of the second material-lined opening;
• epitaxially growing a silicon-comprising layer from the exposed monocrystalline material within the second material-lined opening at a temperature greater than 200° C.;
• and
• after the growing, removing at least a portion of the second material lining prior to cooling the epitaxially grown silicon-comprising material to a temperature below 200° C.

A method of forming a layer comprising epitaxial silicon, comprising:

• providing an opening within a first material received over a monocrystalline material;
• lining opposing sidewalls of the opening with a second material, monocrystalline material being exposed at a base of the second material-lined opening;
• epitaxially growing a silicon-comprising layer from the exposed monocrystalline material within the second material-lined opening at a temperature greater than 600° C.;
• and
• after the growing, in situ etching at least a portion of the second material lining prior to cooling the epitaxially grown silicon-comprising material to a temperature below 600° C.

A method of forming a layer comprising epitaxial silicon, comprising:

• providing an opening within a first material received over a monocrystalline material, the opening comprising opposing sidewalls;
• forming opposing walls within the opening which are laterally displaced inwardly of the opposing sidewalls, a space being received between the opposing walls and the opposing sidewalls;
• and
• epitaxially growing a silicon-comprising layer between the opposing walls from monocrystalline material exposed at a base of the opening.

A method of forming a layer comprising epitaxial silicon, comprising:

• providing an opening within a first material received over a monocrystalline material, the opening comprising opposing sidewalls;
• depositing a second material over the first material within the opening and along the opposing sidewalls and to less than completely fill the opening, the second material being different in composition from that of the first material;
• depositing a third material over the second material within the opening to less than completely fill remaining volume of the opening, the third material being different in composition from that of the second material;
• etching at least some of the second material from between the first and third materials within the opening effective to form a space between the first and third materials;
• and
• after the etching, epitaxially growing a silicon-comprising layer within the opening from monocrystalline material exposed at a base of the opening.