Patent ID: 9536879
Date: 2017-01-03
CPC Classifications: H01L

Claim:
1. A method comprising: forming a plurality of fins on a substrate; forming a gate over a first portion of the plurality of fins, a second portion of the plurality of fins remains exposed; depositing a nitride material above and in direct contact with the gate and the second portion of the plurality of fins; etching the nitride material until a top surface of the second portion of the plurality of fins is exposed, a portion of the nitride material remains on opposite sides of the second portion of the plurality of fins forming sidewall spacers; etching the second portion of the plurality fins to form a trench between the sidewall spacers; epitaxially growing a semiconductor material within the trench to replace the second portion of the plurality of fins, wherein lateral epitaxial growth of the semiconductor material is prevented by the sidewall spacers forming geometrically constrained unmerged source-drain regions; and continuing epitaxially growing the semiconductor material until a top portion of the semiconductor material extends upwardly from the sidewall spacers, wherein epitaxial growth of the top portion of the semiconductor material takes place on a {111} plane, wherein a width of the top portion of the semiconductor material is equal to or less than a width of the geometrically constrained unmerged source-drain regions.