Simple fabrication process of high-density field emission arrays

A simple method using a lithography process for the manufacturing of arrays of high density field emitters is described. SiO2 is formed on the Si substrate, and covered with a metal layer and resist film. The lithography of the ring-shaped patterns and etching them in the metal layer is followed by the electrochemical process in order to increase the metal layer thickness. The insulated dots in the centre of the exposed and the etched rings remain not thickened. This procedure together with ion etching leads to the formation of emitter tips in the Si substrate. The RIE etching allows for precise control of the cone tip radius. Silicon emitters with density of 104 tips/mm2 have already been obtained. This production method may be used for production of metal emitters as well.