Intense electron emission from graphite-nanocrater (GRANC) cold cathode and its application to scanning electron microscopes

Carbon nanotubes (CNTs) have attracted special interest from the point of view of high brightness point electron sources. The best performance of the brightness was reported for a multi-walled CNT. This characteristic seems to be promising for the fabrication of devices with point electron sources such as scanning electron microscopes and transmission electron microscopes. In this paper, the brightness of electron beam from a graphite-nanocrater GRANC cathode is fabricated onto a conical shaped graphite rod by hydrogen plasma etching. A high density electron emission more than 1 A/cm² and brightness of the order of 10¹¹-10¹² Asr^-1m² are obtained. This high brightness is similar to the highest reported performance for CNTs.