Synthesis of carbon nanosheets and carbon nanotubes by radio frequency plasma enhanced chemical vapor deposition

• Published in: Diamond and related materials Vol. 16; no. 2; pp. 196 - 201
• Main Authors: Zhu, Mingyao, Wang, Jianjun, Outlaw, Ronald A., Hou, Kun, Manos, Dennis M., Holloway, Brian C.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-02-2007; Elsevier
• Subjects: Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Graphite; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nanoscale materials and structures: fabrication and characterization; Nanostructures; Nanotubes; Physics; RF plasma enhanced CVD; Theory and models of film growth; RF plasma enhanced CVD; Graphite; Nanostructures; High-frequency discharges; Catalysts; Carbon nanotubes; Crystal growth from vapors; Operating conditions; Inductively coupled plasma; Growth mechanism; PECVD; Electron density; Nanostructured materials; Radiofrequency sputtering; Conformation
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2006.05.007

Carbon nanosheets are a two-dimensional carbon nanostructure consisting of free-standing graphite sheets (∼
1 nm thick) which we deposit using an inductively coupled RF PECVD method. Our previous reports have shown that carbon nanosheets can be grown on a variety of substrates, without catalyst, and under various growth conditions. In this work we describe process details and plasma control parameters to permit rapid changeover from nanotube to nanosheet deposition in the same system. We present a thorough characterization of the nanosheet layer that is produced under these circumstances. We also propose plausible mechanisms to account for the different mode of layer growth leading to the observed topography and conformation of the nanosheets. The experimental evidence suggests that a combination of high plasma electron density and large atomic hydrogen density of the inductively coupled plasma is the reason for nanosheet formation.