AbstractThis paper deals with an optimization of a field-emission structure concept based on vertically aligned carbon nanotubes (CNT). A design concept for a fabrication method for a gate structure based on electron beam lithography is reviewed in the first part of the paper. A single carbon nanotube is grown by the PECVD method inside the gate structure. Calculations and simulations that help determine gate structure proportions in order to obtain the best possible electron reduced brightness and to predict the cathode's electric behavior are also essential parts of this study.