Trench sidewall protection for selective epitaxial semiconductor material formation

摘要

A method of forming a semiconductor device includes forming an insulator layer over a substrate; opening a trench in the insulator layer so as to expose one or more semiconductor structures formed on the substrate; forming a protective layer on sidewalls of the trench; subjecting the substrate to a precleaning operation in preparation for epitaxial semiconductor formation, wherein the protective layer prevents expansion of the sidewalls of the trench as a result of the precleaning operation; and forming epitaxial semiconductor material within the trench and over the exposed one or more semiconductor structures.

主权项

1. A semiconductor device, comprising:
a plurality of semiconductor fins formed on a substrate; an oxide insulator layer formed over the substrate, the oxide insulator layer having a top surface at a height that is above a top surface of the semiconductor fins; a trench formed in the oxide insulator layer, the trench configured to expose a portion of the plurality of semiconductor fins; a protective layer formed on lower sidewalls of the trench, and in contact only with oxide material, the protective layer comprising a material that is resistant to an etchant material that etches oxide, wherein a height of the protective layer is above the top surface of the semiconductor fins, and below the top surface of the oxide insulator layer; and an epitaxial semiconductor material formed within the trench and over the exposed one or more semiconductor structures, wherein a height of the epitaxial semiconductor material is above the top surface of the semiconductor fins and below the height of the protective layer.