FABRICATION AND ELECTRON MICROSCOPY CHARACTERIZATION OF METAL-GATED CARBON NANOTUBE EMITTER ARRAYS

A technique was investigated for the fabrication of triode-type carbon nanotube (CNT) field emitter arrays, where an integrated extraction gate was built between the nanotube cathode and the anode. The gate improves the control capability of emission currents. To fabricate the metal-gated CNT field emitter arrays, well ordered cells were generated by focused ion beam (FIB) milling of platinum (Pt) coated silicon (Si) substrate and then modified by chemical etching. Two types of catalyst elements iron (Fe) and nickel (Ni), were used for growing the CNTs inside the cells. The methods for depositing catalysts into the cells include spin coating sol–gel Fe, FIB induced decomposition of ferrocene and sputter coating pure Ni. CNT growth was carried out by a chemical vapor deposition (CVD) process. The results suggest that the CNTs grew from inside the cells where the catalysts were located. In comparison, the CNTs synthesized from the sol–gel Fe catalyst were straighter than those from ferrocene Fe and pure Ni. The density and orientation of the CNTs in each cell are directly related to the type and quantity of the catalysts and are also affected by the size of the cells.