Method of epitaxial doped germanium tin alloy formation

摘要

A method for forming germanium tin layers and the resulting embodiments are described. A germanium precursor and a tin precursor are provided to a chamber, and an epitaxial layer of germanium tin is formed on the substrate. The germanium tin layer is selectively deposited on the semiconductor regions of the substrate and can include thickness regions of varying tin and dopant concentrations. The germanium tin layer can be selectively deposited by either alternating or concurrent flow of a halide gas to etch the surface of the substrate.

主权项

1. A method of selectively forming doped GeSn layers on a substrate, sequentially comprising:
positioning a substrate in a processing chamber, wherein the substrate comprises both dielectric and non-dielectric surfaces; co-flowing a germanium hydride precursor, a tin precursor and a dopant into the processing chamber, the germanium hydride precursor having a general formula of GenH 2n+2), wherein n is greater than one, to epitaxially grow a GeSn layer until a desired layer thickness is reached; flowing an etchant comprising a halide gas into the processing chamber; and repeating the co-flowing and the flowing an etchant until a GeSn stack of a desired stack thickness is selectively grown on the non-dielectric surfaces.