Gated Si field emitter array prepared by using anodization

High aspect-ratio gated field emitter arrays have been fabricated using silicon tip prepared by the anodization of a silicon wafer with periodic nip junctions. The tips were formed by the preferential growth of porous silicon in p-type material and were transferred to a separate silicon substrate by direct bonding. Gate electrodes were then formed by depositing a WSi₂ film over the tips, and apertures were subsequently created by etching with an argon milling process. The resulting gated tip arrays demonstrated field emission, although higher than usual gate voltages were required.