Novel design considerations for high efficiency carbon nanotube field emitters

High-current field emitters with high operational stability are in demand for a number of applications, including electronic and important military use. In the present research, such a field emitter is designed through application of interface engineering and three-dimensional (3-D) design in a carbon nanotube (CNT) based field emitter. Field emission characterization of the emitter shows low turn-on field, low threshold field, very high emission current density, along with good emission stability and excellent resistance to structural damage. Interface engineering plays an important by offering lower CNT-substrate interfacial resistance and strong interfacial bonding between substrate and CNTs. On the other hand, 3-D design increases CNTs emitters and provides protection against structural damage. Both these features promote high emission current density. Novel design, excellent properties and a simple, scalable three-step processing route make this CNT-based emitter a viable option for high current-density field emission devices.