摘要 |
An electron emission device adapted to enhanced electron beam focusing and its method of fabrication are shown. The device includes driving electrodes for controlling the emission of electrons from electron emission regions formed on a substrate; two or more tiers of insulating layers formed on the driving electrodes; and a focusing electrode formed over the tiers. A multi-tiered insulating layer allows a thick tier to hold the focusing electrodes away from the emission regions, thus enhancing their focusing impact, while a thin tier under the focusing electrodes remains amenable to intricate patterning. Fabrication of the tiers from material with different etching rates allows thicker lower support tiers to be etched during the same period and in the same step that a thinner upper tier is etched, also allowing openings in a lower tier to widen while openings in the upper tier stay small.
|