Hybrid aspect ratio trapping

摘要

A semiconductor structure includes a material stack located on a surface of a semiconductor substrate. The material stack includes, from bottom to top, a silicon germanium alloy portion that is substantially relaxed and defect-free and a semiconductor material pillar that is defect-free. A dielectric material structure surrounds sidewalls of the material stack and is present on exposed portions of the semiconductor substrate.

主权项

1. A method of forming a semiconductor structure, said method comprising:
forming a blanket layer of a silicon germanium alloy directly on a semiconductor material surface of a semiconductor substrate, wherein said blanket layer of said silicon germanium alloy is strained and defect-free; forming a blanket layer of a hard mask material on said blanket layer of said silicon germanium alloy; patterning said blanket layer of said hard mask material and said blanket layer of said silicon germanium alloy to provide a material stack on said semiconductor material surface of said semiconductor substrate, said material stack comprising, from bottom to top, a silicon germanium alloy portion that is substantially relaxed and defect-free and a hard mask material portion; providing a dielectric material structure surrounding sidewalls of said material stack and present on exposed portions of said semiconductor substrate, wherein said dielectric material structure has an topmost surface that is coplanar with a topmost surface of said hard mask material portion; removing said hard mask material portion; and epitaxially growing a semiconductor material pillar on a topmost surface of said silicon germanium alloy portion, said semiconductor material pillar is defect-free.