Field Emission Properties of Carbon Nanotube Thin Films Grown on Different Substrate Materials

The electron field emission characteristics from multiwalled carbon nanotube (MWNT) films grown on two different substrate materials have been studied in this paper. The MWNT films were grown on a flat conductor surface (stainless steel) and a flat insulator surface (quartz). The field emission experiments were carried out under a diode configuration. It was found that the film on the quartz surface exhibits better emission capability, while the film on the stainless steel surface shows better emission stability. Energy-dispersive X-ray spectroscopy analysis revealed that carbon atoms evaporated and deposited on the surface of anode during field emission, which is in agreement to studies previously reported in literature. It is estimated that the degradation was due to local heating of tips of CNTs, leading to evaporation and deposition of carbon atoms during the field emission process.