A new fabrication process of field emitter arrays with submicron gate apertures using local oxidation of silicon

The field emitter arrays with submicron gate apertures for low voltage operation have been successfully fabricated by modifying the conventional Spindt process. The key element of the new process is forming the gate insulator by local oxidation of silicon, resulting in the reduction of the gate hole size due to the lateral encroachment of oxide. The gate hole diameter of 0.55 μm has been obtained from the original mask pattern size of 1.55 μm. An anode current of 0.1 μA per emitter is measured at the gate voltage of about 53 V, while the gate current is less than 0.3% of the anode current. To obtain the same current level from a Spindt-type emitter with the same gate hole diameter as the mask pattern size, a gate bias of about 82 V is needed.