Improving the emission characteristics of a carbon nanotube cathode in an aging process

Aging of the field emission performance of the printed carbon nanotubes (CNTs) cathode is studied. A continuous increase of the field emission current as well as the density of field emission sites under a constant voltage is observed. It is revealed that the resistant heating may play an important role in the activation of the potential emitters during the aging process. A technique of activating the printed CNT cathode with an aging process is suggested. F–N curves before and after the aging processes are analyzed and it is revealed that the effective emission area increases during the aging process.