DC plasma enhanced growth of oriented carbon nanowall films by HFCVD

• Published in: Diamond and related materials Vol. 16; no. 4; pp. 1240 - 1243
• Main Authors: Dikonimos, Th, Giorgi, L., Giorgi, R., Lisi, N., Salernitano, E., Rossi, R.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-04-2007; Elsevier
• Subjects: Bias growth; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; General equipment and techniques; Hot filament CVD; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotubes; Physics; Plasma CVD; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Bias growth; Nanostructure; Plasma CVD; Hot filament CVD; Methane; Hot filament chemical vapor deposition; Growth rate; Carbon nanotubes; Nanostructures; Rare gases; Precursor; Film growth; Thin films; Morphology; Growth mechanism; PECVD; Surface area; Biosensors; IV characteristic; Current density; Nanostructured materials
• DOI: 10.1016/j.diamond.2006.11.073
• EISSN: 1879-0062
• ISSN: 0925-9635

Two dimensional graphitic carbon structures, commonly referred to as carbon nanowalls (CNW), are raising increasing interest in the scientific community. Their surface area is theoretically twice that of the closed boundary structures, such as carbon nanotubes, making them extremely attractive for chemical and biosensor applications.
In this work CNW, with maximum longitudinal dimension ranging from 10 to 200 nm and wall thickness lower than 5 nm, have been grown in a HFCVD reactor on Si substrates. The growth precursors consisted of methane diluted into He noble gas. The effect of a DC plasma on the growth rate and film morphology was explored. The experimental setup consisted of a two grid system which allowed to vary independently the plasma voltage and current density on the substrate surface. An increase of growth rate was observed as the film thickness increased from a few nanometers to about 200 nm when the substrate current density was increased from 0 to 3.5 mA/cm
2 for 30 min.