Emission and Focusing Characteristics of a Quintuple-gated Field Emitter Array

A eld emitter array (FEA) with a ve-stacked gate electrode, that is, a quintuple-gated FEA with a four-stacked electrode lens, was fabricated. The four-stacked electrode forms an einzel lens where the second and third electrodes are connected through a contact hole. Because the electron velocity of the einzel lens in a quintuple-gated FEA is smaller than that of the quadruple-gated FEA, the quintuple-gated FEA has a stronger electron convergence. The slit sweeping method conrmed that a beam crossover is formed for the quintuple-gated FEA. A field emitter array (FEA) with a focusing electrode is an appealing device for electron beam lithography,1) high definition field emission displays,2) and image sensors.3) Previously, the fabrication and characteristics of a double-gated FEA with two-stacked electrodes have been reported.4{6) Double-gated FEAs can effectively generate a focused electron beams. How-ever, one drawback to a double-gated FEA is drastic reduction in the emission current under the focusing condition due to the decreased field enhancement at the emitter tip caused by the low potential of the vicinal focusing electrode.4) Recently, we reported a volcano struc-tured field emitter comprised of a focusing electrode located below the extraction gate (Gex) electrode.7,8) This volcano structured FEA is the first to focus the electron beam withou