Electron emission properties of carbon nanotubes

Abstract We report on the field emission properties of carbon nanotubes, focusing on current density versus electric field ( J – F ) characteristics and the spacing between the emitter and collector. We grew carbon nanotubes on SUS304, nickel, Inconel-600, and Invar-42 substrates using plasma-enhanced chemical vapor deposition, using methane gas as the carbon source and hydrogen gas as the catalyst and dilution gas. We found that nanotubes grew fastest on Invar-42. Nanotubes were distributed from 50 to 100 nm in diameter and from 1 to 30 μm long. Onset field of the field emission was 0.7 V/μm and the current density was 1 mA/cm 2 at an electric field of 3.0 V/μm. A Fowler–Nordheim plot was made. Field enhancement factor β and emission area α were calculated and compared between substrates. Using nickel on quartz glass, carbon nanotubes were selectively fabricated on metal lines on quartz glass.