Nanowire metal-oxide-semiconductor field effect transistor with doped epitaxial contacts for source and drain

The authors report the fabrication of a p-field effect transistor (FET) and an n-FET with a silicon nanowire channel and doped silicon source and drain regions. The silicon nanowires were synthesized by the vapor-liquid-solid method. For p-FETs the source and drain regions were formed by adding boron doped silicon to the unintentionally doped nanowire body at predefined locations using in situ doped silicon epitaxy. For n-FETs the epitaxial source and drain regions were grown undoped and were later implanted with P and As. The measured I-d-V-g characteristics of the devices exhibited unipolar transport, while reference FETs made with nanowires from the same batch but with Schottky (metal) contacts exhibited ambipolar characteristics. (c) 2007 American Institute of Physics.