Field emission from amorphous-carbon nanotips on copper

Abstract

Amorphous-carbon (a-C) nanotips were directly grown on copper substrates by microwave plasma-enhanced chemical-vapor deposition. The length of a typical a-C nanotip is ϳ250 nm and its tip diameter is ϳ25 nm. The in-plane correlation length La, equivalent to the size of the sp 2 clusters, is determined to be 1.2 nm through the intensity ratio of the D and G peaks in the Raman spectrum, which is about in the optimum range for field emission. A low turn-on field of 1.6 V/m at 10 A/cm 2 , a threshold field of 3.8 V/m at 10 mA/cm 2 , and a high current density of 32.42 mA/cm 2 at 4.0 V/m are achieved. The field emission characteristics of a-C nanotips are close to those of carbon nanotubes, and much better than what has been reported for flat diamond-like carbon or a-C:H coated cathodes. The roles of the sp 2 cluster size, electron confinement and conductivity in the field emission of a-C nanotips are discussed.

Self-Assembled Fabrication and Characterization of Vertically Aligned Binary CN Nanocone Arrays

“…of various materials, e.g., carbon, diamond, BCN, AlN, and SiCN, have attracted significant scientific and technological interest due to their unique mechanical, electrical, optical, and chemical properties. [1][2][3][4] Among these, carbon-based nanostructures, such as graphite-and diamondstructured nanocones, have been demonstrated to be promising for applications in electron-emitting panels, tips for microscopes, sensors, solar cells, supercapacitors, and various nanoelectronic devices. [2][3][4] In resent years, efforts have been directed towards finding self-assembly processes to fabricate such nanostructures with high aspect ratios and good mechanical and chemical stability.…”

Synthesis of Crystalline Carbon Nitride Nanocone Arrays by Direct‐Current Discharge Plasma‐Assisted CVD

“…Among the NCs, the arrayed pure carbon NCs, such as graphite-and diamond-structured NCs, have been demonstrated to be promising in the application of electron field microemitters, as well as probes for atomic force microscopy (AFM). [2][3][4] It has been known that both graphite and diamond NCs have good field emissivity, but diamond is insulated and graphite is not of sufficient mechanical strength. An interesting possibility of the partial substitution of carbon in pure carbon NCs, leading to the formation of binary CN curve compound ones, has been theoretically predicted.…”

“…and chemical properties. [1][2][3][4] Efforts are directed to finding self-organized processes to fabricate such kinds of nanostructures with sharp apex angles to enhance the field emission efficiencies, and with good mechanical and chemical stabilities. Among the NCs, the arrayed pure carbon NCs, such as graphite-and diamond-structured NCs, have been demonstrated to be promising in the application of electron field microemitters, as well as probes for atomic force microscopy (AFM).…”

Study on formation and shape of carbon nanotips depending on ion bombardment

“…These data indicate that they are the most promising material for field emission display emitters. The carbon nanotips have been successfully synthesized by plasma-enhanced chemical vapor deposition (CVD) on silicon and copper substrates with or without catalysts and the growth mechanism has widely been researched [1][2][3][4]. However, the mechanism has not been well understood.…”