New fabrication method of silicon field emitter arrays using thermal oxidation

Abstract

The fabrication and emission characteristics of a silicon field emitter array using pure thermal oxide as a gate insulator are described. Since the thermally grown oxide film has a better stoichiometry and is a better insulator than the evaporated oxide, the fabrication process could be stabilized and the tip-to-tip uniformity improved. In addition, the aspect ratio can be controlled easily by this process free from the shadowing effect that appears in the evaporation process. Fabricated samples have been measured electrically in the vacuum of 1×10−8 Torr. The anode current of 290 nA (37 nA) for a single tip was observed at the gate voltage of 130 V (100 V), and the gate current was less than 1% of the emission current. The emission patterns of a 625-tip array showed a very uniform phosphor luminescence due to the averaging effect resulting from the multiple silicon tips.