Method for manufacturing a low voltage driven field emitter array

Abstract

The present invention provides a method for manufacturing a low voltage driven field emitter array, comprising steps of forming a thin buffer layer on a silicon substrate, making a pattern with lots of silicon nitride masks on the layer, oxidizing the upper part of the substrate and forming a relatively thick oxide layer onto the substrate except the part under the nitride masks, during which the thick oxide layer upheaves the edges of the nitride masks and extends inwardly under the nitride masks so that the edges of the thick oxide layer under the nitride masks may have a kind of bird's beak shape in cross section, etching away the nitride mask pattern, exposing the silicon substrate for the circular parts surrounded by the bird's beak shape edges by etching away the thin buffer layer, etching away the exposed substrate for making gate holes of undercut shape, and forming metal layers on the substrate and the bottom of the gate holes by evaporating a matalic evaporant downwardly and vertically against the surface of the substrate. The diameter of the gate hole is reduced in comparison to that defined by the photomask and the FEA may be driben at relatively lower voltages.