Surface-conducted field emission electron sources with ZnO emitters of different morphologies

Surface-conducted field emission electron sources using ZnO nanostructures as surface-conducted emitters have been successfully fabricated, where the linear cathode and gate electrodes were interdigitated and paralleled on the same plane and ZnO emitters with different morphologies were deposited in the gap between the cathode and gate electrode. Field emission investigations indicate that the turn-on voltage of the fabricated SCFE electron sources with ZnO nanorods, ZnO nanotubes, and ZnO nanocones modifies from 260 V to 220 V at the anode voltage of 2 kV. The emission efficiency of SCFE electron source with ZnO nanocones is as large as 43.6%, which is much higher than that of SCFE electron sources with ZnO nanorods and nanotubes at the gate voltage of ∼300 V. The whole surface emission of the fabricated electron source with ZnO nanocones on the fluorescent screen is more homogeneous than that of the electron sources with ZnO nanorods and nanotubes.