Double-gated field emitter array with carbon nanotubes grown by chemical vapor deposition

We fabricated 4.75in. diagonal field emitter arrays with a double-gated structure in which the carbon nanotubes were synthesized by chemical vapor deposition using CO and H2 as feed gases. The nanotubes grown directly inside gate holes were used as an emitter. The diameter of the gate hole opening was as small as 4μm, accompanied with a large number of gate holes in a pixel. The electron beam spreading was minimized by employing a focus electrode. It was found that neither anode voltage nor focus electrode voltage had a strong influence on the anode current. The pixel-to-pixel uniformity of the fabricated structure was measured to be about 91%. Considering the limitation of the structure that has only a vertical resistive layer, it can be said that the fabricated field emitter shows quite a good uniformity.