Abstract
Carbon nanotube morphology has been engineered via simple control of applied voltage during dc plasma chemical vapor deposition growth. Below a critical applied voltage, a nanotube configuration of vertically aligned tubes with a constant diameter is obtained. Above the critical voltage, a nanocone-type configuration is obtained. The strongly field-dependent transition in morphology is attributed primarily to the plasma etching and decrease in the size of nanotube-nucleating catalyst particles. A two-step control of applied voltage allows a creation of dual-structured nanotube morphology consisting of a broad base nanocone (∼200 nm dia.) with a small diameter nanotube (∼7 nm) vertically emanating from the apex of the nanocone, which may be useful for atomic force microscopy.
Original language | English |
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Article number | 3 |
Pages (from-to) | 5373-5375 |
Number of pages | 3 |
Journal | Applied Physics Letters |
Volume | 85 |
Issue number | 22 |
DOIs | |
State | Published - 29 Nov 2004 |
Bibliographical note
Funding Information:The authors acknowledge the support of the work by University of California Discovery Fund under Grant No. ele02-10133/Jin, NSF NIRTs under Grant Nos. DMI-0210559 and DMI-0303790, and Lawrence Livermore National Laboratory under Grant No. MI-04-006.