Contact structure and extension formation for III-V nFET

摘要

FinFET devices including III-V fin structures and silicon-based source/drain regions are formed on a semiconductor substrate. Silicon is diffused into the III-V fin structures to form n-type junctions. Leakage through the substrate is addressed by forming p-n junctions adjoining the source/drain regions and isolating the III-V fin structures under the channel regions.

主权项

1. A method comprising:
obtaining a semiconductor structure including a semiconductor substrate and a plurality of columns extending from the semiconductor substrate, the columns being separated by a plurality of recesses, each of the columns including a III-V base and a III-V fin structure, the III-V fin structure being positioned on the III-V base; epitaxially growing a silicon-containing layer on the semiconductor substrate and within the recesses such that a portion of the silicon-containing layer adjoins the III-V fin structures, wherein epitaxially growing the silicon-containing layer includes epitaxially growing a first, p-type silicon layer on the semiconductor substrate and a second silicon layer on the first, p-type silicon layer; causing diffusion of silicon from the silicon-containing layer into the III-V fin structures to form n-type junctions, and forming n-type source/drain regions from the second silicon layer.