Improved field-emission properties of carbon nanotube field-emission arrays by controlled density growth of carbon nanotubes

The density distribution of CNTs is one of the crucial parameters determing the field-emission property of CNTs. To effectively control the density of CNTs, an inactive thin-film layer was deposited on a catalyst. The results showed that improved field emission property could be obtained with a thin SiO layer on the catalyst layer as the precursor. For 3.5 nm Fe and 3.5 nm SiO on 3.5 nm Fe as a catalyst, the turn-on field could be decreased from 3.7V/μm. to 2.2 V/μm and the field-emission current density increased from 2.6 × 10-8 A/cm2 to 2.4 × 10-4 A/cm 2 when the applied field was 4 V/μm. © 2005 the japan society of applied physics.