Large field emission current and density from robust carbon nanotube cathodes for continuous and pulsed electron sources

Abstract

Highly adhesive cold cathodes with high field emission performance are fabricated by using a screen-printingmethod. The emission density of carbon nanotube (CNT) cold cathode reaches 207.0 mA cm−2 at an electric field of 4.5 V μm−1 under continuous driving mode, and high peak current emission of 315.8 mA corresponding to 4.5 A cm−2 at the electric field of 10.3 V μm−1 under pulsed driving mode. The emission patterns of the cold cathodes are of excellent uniformity that was revealed by vivid luminescent patterns of phosphor coated transparent indium tin oxide (ITO) anode. The cold cathodes also exhibit highly stable emission under continuous and pulsed driving modes. The high adhesion of CNTs tomolybdenum substrates results in robust cold cathodes and is responsible for the high field emission performance. This robust CNT emitter could meet the operating requirements of continuous and pulsed electron sources, and it provides promising applications in various vacuummicro/nanoelectronic devices.