Controlled confined lateral III-V epitaxy

A method of forming a semiconductor structure comprising:

• forming dielectric material layer over a sacrificial semiconductor layer that is located over a region of an insulator layer, wherein the sacrificial semiconductor layer comprises silicon-germanium having a first germanium concentration;
• forming a first trench opening extending through the dielectric material layer and the sacrificial semiconductor layer, wherein the first trench opening exposes a first sidewall of the sacrificial semiconductor layer;
• oxidizing the sacrificial semiconductor layer to form an oxide region over the first sidewall of the sacrificial semiconductor layer and a germanium-enriched region within the sacrificial semiconductor layer and adjoined to the oxide region, wherein the germanium-enriched region has a second germanium concentration greater than the first germanium concentration;
• forming a second trench opening extending through the dielectric material layer and the sacrificial semiconductor layer, wherein the second trench opening exposes a second sidewall of the sacrificial semiconductor layer opposite to the first sidewall;
• removing the sacrificial semiconductor layer to provide a trench, wherein the trench exposes a sidewall of the germanium-enriched region;
• forming a semiconductor barrier layer over the exposed sidewall of the germanium-enriched region;
• growing a III-V compound semiconductor material within the trench and laterally outwards from a sidewall surface of the semiconductor barrier layer to provide a III-V compound semiconductor layer;
• and
• removing a defect-containing region of the III-V compound semiconductor layer.