Field emission of carbon-nanotube point electron source

• Published in: Diamond and related materials Vol. 18; no. 12; pp. 1435 - 1439
• Main Authors: Lim, Seong Chu, Lee, Dae Sik, Choi, Ha Kyu, Lee, Il Ha, Lee, Young Hee
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.12.2009; Elsevier
• Subjects: Carbon nanotubes (CNT); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Dielectrophoresis; Disintegration; Electron and ion emission by liquids and solids; impact phenomena; Electron sources; Emission; Emittance; Emitters (electron); Exact sciences and technology; Field emission; Field emission, ionization, evaporation, and desorption; Fluctuation; Materials science; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Other topics in nanoscale materials and structures; Physics; Point electron source; Threshold currents; Field emission; Carbon nanotubes (CNT); Dielectrophoresis; Point electron source; Critical points; Carbon nanotubes; Threshold current; Low field; Electric currents; Multiwalled nanotube; Electric field effects; Electron sources; Nanostructured materials
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2009.09.010

Carbon nanotube (CNT)-based point electron emitter was fabricated using a cavity-confined dielectrophoresis. The emission current of an individual multi-walled CNT (MWCNT) was stable up to 10 μA and reached ~ 2 mA (1.7 × 10 8 A/cm 2), about three orders of magnitude higher than the threshold current of the existing single MWCNT tip. At low electric field, the current fluctuated in a stepwise manner. On the other hand, above critical field, CNT point emitter started to disintegrate so that the current fluctuated rapidly and gradually diminished. These anomalous behaviors were explained from the cap opening and field-induced unraveling of tip edges.