Effective radial modulus (Eradial) of straight single-walled carbon nanotubes (SWCNTs) grown directly on quartz substrate have been measured by using well-calibrated tapping mode and contact mode atomic force microscopies. It is found that the measured Eradial decreases from 57 to 9 GPa as the diameter of the SWCNTs increases from 0.92 to 1.91 nm. The current experimental results are consistent with the recently reported simulation data in both the data pattern and values. The method used in this research can also be applied to measure the mechanical properties of other low-dimension nanostructures, such as nanowires and nanodots.

Fabrication of gated cathode structures using an in situ grown vertically aligned carbon nanofiber as a field emission elementWe report on the fabrication of arrays of free-standing carbon nanofibers ͑CNFs͒ individually addressable on the 50 nm scale. The template for CNF growth consists of a set of tungsten leads patterned with a catalyst dot at the tip of each terminal. The fabrication process involves electron-beam lithography, projection photolithography, reactive ion etching, and dc plasma-enhanced chemical vapor deposition. Discharge power is found to drastically influence the morphology of CNFs grown off single catalyst dots.

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