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We present, for the first time, a prototype active-matrix field emission display (AMFED) in which an amorphous silicon thin-film transistor (a-Si TFT) and a molybdenumtip field emitter array (Mo-tip FEA) were monolithically integrated on a glass substrate for a novel active -matrix cathode (AMC) plate. The fabricated AMFED showed good display images with a low-voltage scan and data signals irrespective of a high voltage for field emissions. We introduced a light shield layer of metal into our AMC to reduce the photo leakage and back channel currents of the a-Si TFT. We designed the light shield to act as a focusing grid to focus emitted electron beams from the AMC onto the corresponding anode pixel. The thin film depositions in the a-Si TF Ts were performed at a high temperature of above 360 ° C to guarantee the vacuum packaging of the AMC and anode plates. We also developed a novel wet etching process for n + -doped a-Si etching with high etch selectivity to intrinsic a-Si and used it in the fabrication of an inverted stagger TFT with a very thin active layer. The developed a-Si TFTs performed well enough to be used as control devices for AMCs. The gate bias of the a-Si TFTs well controlled the field emission currents of the AMC plates. The AMFED with these AMC plates showed lowvoltage matrix addressing, good stability and reliability of field emission, and good light emissions from the anode plate with phosphors.

A novel patterning technology of fine-pitched carbon nanotube (CNT) pixels on a thin metal has been developed by lift-off process for field emitter arrays (FEAs). The lift-off method provides even smaller CNT pixels compared with those made by conventional screen-printing and photolithography processes. SEM images demonstrated that the smallest pitch and the size of patterned pixels were 15 μm × 15 μm and 7 μm × 7 μm, respectively. After patterning and heat treatment process at 300°C, most of CNT bundles on the cathodes were aligned perpendicular to the substrate. The density of CNT bundles in the patterned pixels was 10–20/μm2. The turn-on field of patterned CNTs was less than 2.5 V/μm and the current density was 3.2 mA/cm2 at 3.5 V/μm.