Field emission data from aligned graphitic nanofibers have been obtained. The aligned nanofibers are 50–100 nm in diameter and 6–10 μm in length, with a density of 109–1010/cm2. The fibers were grown on polycrystalline nickel substrate by plasma-assisted hot filament chemical vapor deposition using a gas mixture of nitrogen and acetylene. The onset of emission current in microampere level was detected at about 1.8 V/μm with an emission area of 1 mm2. The Fowler–Nordheim model was used to analyze the data obtained. The field emission current required for flat panel display can be easily achieved at 2.5 V/μm.

A 0.65-0.70eV luminescence peak in a-Si: H films after illumination is reported. It is found that exposure to light decreases total integrated intensity of luminescence and also produces two luminescence peaks, one is in the range 0.80-0.90eV, and the other is in 0.65-0.70eV. The former disapears by annealing at 190°C, but the latter can not be removed. Similar luminescence peaks are observed in a-Si: H films prepared under higher RF power without illumination.