Field emitter technology for nanovision science

A field emitter (FE) capable of focusing an electron beam is an attractive device for application, such as ultrafine imaging devices, a scanning electron microscope and electron beam lithography. We have developed multi-gated field emitters such as a quadruple-gated FE with a three-stacked electrode lens and a quintuple-gated FE with a four-stacked electrode lens. Both the FEs can focus the electron beam. However, the quintuple-gated FE has a stronger electron convergence than the quadruple-gated FE, and a beam crossover is clearly observed for the quintuple-gated FE.