Field emission characterization of CNT-coated paper and laboratory tissue emitters with variable tip angles

Field emitters are important elements of many scientific applications, such as X-ray sources, electron microscopes, electron beam lithography and displays. The fabrication of field emitters is technologically challenging; therefore, current research efforts focus on improving existing methods and developing new approaches that enable fast, simple, and low-cost fabrication of field emitters. Here we show a simple fabrication method and measurement results of field emitters with different tip angles made from paper and laboratory tissue, which were coated with CNTs (Carbon Nanotubes). Field emitters were cut using office scissors, immersed in a CNT solution and dried in air for at least 24 h. Current-voltage characteristics were measured, long-term stability tests lasting 1 h were performed, and structural degradation was analyzed using SEM. Comparisons were conducted with emitters of different tip angles from both materials. The results confirm the feasibility of our method. Emission currents of up to 300 µA were achieved. Independent of this, stable long-term operation in the 1-15 µA range was demonstrated, and the influence of emission current and emitter angle on structural degradation was identified. These results demonstrate the potential of using readily available materials like paper and laboratory tissue with CNT coating for low-cost field emitters suitable for applications requiring high emission currents.