Development of an Electron Emitter via Seamless Shaping of a 3D-Printed Ceramic Cone With Carbon Nanotube Mesh Film as an Alternative to Polymer-Based Materials

Abstract

This paper focuses on electron emitters formed using seamless hybrid shaping of the ceramic 3D-printed cone (as a supporting structure) and a conductive emitting film obtained from the suspension of dispersed carbon nanotubes (CNT). The ceramic cone is post-process fired to achieve a pure ceramic cone that is coated with emitting CNT mesh film. Meanwhile, a cone-based polymer emitter is evaluated. The resulting emitter exhibits non-linear current-voltage characteristics reaching maximum 0.6 mA anode current with a turn-on-field voltage below 1 Vµm⁻¹ and minimal current fluctuation over time. Additionally, the ceramic emitter arrays fabricated using the same technique are demonstrated: if the tip angle and shape in a microscale have tunability in emission is confirmed, meanwhile, the type of volatile gases released during the emission is confirmed using a residual gas analyzer (RGA). The motivation and challenge are to use 3D printing to enable freedom in designing and forming the emitter tip shape and angle and to present the perspective and challenges to use the 3D printing technique combined with the seamless shaping for the CNT mesh film to tune the emitter performance. Especially as this technique and 3D-printed materials have not been previously employed for electron emitters.