Low voltage driven carbon nanotube field emission cathode

An under-gate CNT cathode structure was fabricated and characterized. The purpose of this work is to fabricate a cathode with micron-sized CNT-to-counter electrode gap, d/sub G/. Scanning electron microscopy was used to characterize the fabricated cathode. Electrical measurements were made in a vacuum chamber. It was found that cathode-to-gate voltage decreases with decreasing d/sub G/. It was also observed that emitting layer made of high purity CNT powder offers higher performance in terms of emission site density.