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An effective method is described for the production of ultrasharp vertically oriented silicon nanocones with tip radii as small as 5 nm via an acetylene and ammonia dc plasma process. The mechanism for the formation of these structures is reactive ion etching of the silicon substrate facilitated by copper seed particles and it is shown that by patterning the seed and etch barrier materials the location of the nanocones can be predetermined.

Electron microscopy and magnetic properties of Fe-Co alloy catalysts used for the synthesis of vertically aligned carbon nanofiber (VACNF) are described. The nanofibers are grown by dc plasma-enhanced vapor deposition (PECVD) and the magnetic properties are measured with a superconducting quantum interference device based magnetometer.

The advance development in surface analysis techniques used to characterize the surface structure and chemistry of carbon nanofibers and related carbon materials are reviewed. Some of the techniques reviewed include scanning probe microscopy, infrared and electron spectroscopies, electron microscopy, ion spectrometry, temperature-programmed desorption, and atom probe analysis.

Isolated vertically aligned carbon nanofiber (VACNFs) are grown using dc plasma-enhanced chemical vapor deposition, and the effects of the growth conditions on VACNF morphology and composition are determined. The results indicate the importance of plasma control for the deterministic growth of isolated VACNFs.

Field emission (FE) from isolated individual vertically aligned carbon nanocones (VACNCs) is measured using a small-diameter moveable probe. Isolated VACNCs show a strong dependence of the FE turn-on field on their aspect ratio.