Abstract
Ultra Nano Crystalline Diamond (UNCD) films and lateral emitters comprising UNCD were grown by using microwave plasma-enhanced chemical vapor deposition (MPCVD). We have investigated and discussed about how to improve the nucleation of UNCD films as well as the field emission properties of UNCD films and lateral emitters made by UNCD. Experiments were carried out with different powder composition to enhance ultrasonication nucleation and also studied the effects on the electric filed emission properties. We have found that the Ti and NCD mixed powder in methanol solution enhanced the morphology of the UNCD film with very small thickness (<200 nm) and its field emission property was also better than the other nucleation methods. To fabricate the UNCD lateral emitter, we have used sacrificial layer process and investigated the effect of geometric changes on the field emission properties. Lateral emitter with very small gap between the electrodes was fabricated (< 2 □m) with markedly reduced turn-on voltage. The increase in the number of tips and reduce in the cathode to cathode distance were also made in practice to increase the current density. Finally, we have used three different fabrication processes to fabricate the lateral emitter and studied its effect on the field emission properties. Efforts have been made to find an easy and convenient process to fabricate the UNCD lateral emitter with the field emission properties as best as possible.