Analysis of the behavior of individual emission sites on the surface of a multi-tip field cathode

A method of analysis of the surface of multi-tip field cathodes using data obtained with the aid of a computer-controlled field emission projector and a system of fast high-voltage scanning is described. An investigation of a polymer/carbon nanotube composite field electron emitter by this method was used to determine the distribution of individual emission sites over the surface of a multi-tip field cathode and to estimate variation of the work function of separate emission sites depending on the applied voltage. The contributions of separate groups of emission sites to a change of the shape of current–voltage characteristic of a multi-tip cathode have been numerically estimated.