Improvement of field emission properties of CNTs by high-temperature heat treatment

Field emission characteristics of CNT paste emitters were improved using the CNTs annealed at high temperatures of 1400~2000°C in Ar. The annealing considerably enhanced the crystallinity of CNTs, as indicated by an increase of their I_G/I_D ratios and TGA oxidation temperatures. With such highly crystalline CNTs engaged, the turn-on electric fields and long-term emission stability of the CNT pastes were also greatly improved.