Superior integrated field emission cathode with ultralow turn‐on field and high stability based on SiC nanocone arrays

Abstract

Abstract Low turn‐on field ( E to ) and stable electron emission are two of key parameters for reliable application of field emission (FE) cathodes. In the present work, we developed a novel high‐performance integrated field emission cathode based on well‐aligned SiC nanocone arrays via an electrochemical etching approach. The etched SiC nanocone emitters and the underlying remaining SiC wafer are designed into a single‐crystalline integrated architecture without interfaces, which favors cathodes with a sturdy configuration to resist Joule heat during long period electron emission process and structural failure caused by the existed strong electrostatic forces. Accordingly, the E to of the integrated SiC cathode is reduced to 0.32 V/μm, which is the lowest value among all the previously reported SiC nanostructured emitters. In addition, the integrated cathode presented superior stability with an electron emission fluctuation of 3.3% over 10 h. This work provides a new perspective for designing and fabricating advanced FE cathodes for further promising applications in harsh working conditions with high performance.