EPITAXIAL GROWTH OF SILICON FOR FINFETS WITH NON-RECTANGULAR CROSS-SECTIONS

摘要

FinFET devices with epitaxially grown fins and methods for fabricating them are provided. Embodiments include forming at least two shallow trench isolation (STI) regions, filled with dielectric material, adjacent to but separate from each other in a silicon substrate; epitaxially growing a silicon-based layer between each adjacent pair of STI regions to form a fin with a non-rectangular cross-section extending from each STI region to each adjacent STI region; forming a gate oxide over and perpendicular to each fin; and forming a gate electrode over the gate oxide to form a FinFET.

主权项

1. A method comprising:
forming at least two shallow trench isolation (STI) regions, filled with dielectric material, adjacent to but separate from each other in a silicon substrate; epitaxially growing a silicon-based layer between each adjacent pair of STI regions to form a fin with a non-rectangular cross-section extending from each STI region to each adjacent STI region; forming a gate oxide over and perpendicular to each fin; forming a gate electrode over the gate oxide to form a FinFET; and performing a well implantation between each pair of adjacent STI regions either prior to epitaxially growing the silicon-based layer, subsequent to epitaxially growing the silicon-based layer but prior to forming the gate oxide, or prior to anisotropically wet etching the silicon substrate, wherein the epitaxially grown silicon-based layer forms a fin with a diamond-shaped cross-section between each pair of adjacent STI regions, the diamond-shaped cross section comprising two sides meeting at a single point above the surface of the silicon substrate.