FIELD EMITTER WITH FOCUSING RIDGES

摘要

A gated field-emission structure contains an emitter electrode (46), an overlying electrically insulating layer (48), and one or more electron-emissive elements (52) situated in one or more apertures extending through the insulating layer. A patterned gate electrode (50) through which each electron-emissive element is exposed overlies the insulating layer. Focusing ridges (54) are situated on the insulating layer on opposite sides of the gate electrode. The focusing ridges, which normally extend to a greater height than the gate electrode, cause emitted electrons to converge into a narrow band.