Modeling basic tip forms and its effective field emission parameters

Abstract

One of the important parameters of the single-tip emission system is the total emission current from the tip. To obtain the distribution of the field enhancement factor over the tip surface, we provided comsol simulation for different tip shapes. Current-voltage characteristics are obtained by integrating the current density over the emitter surface. Several types of current density formulas with different degrees of accuracy were used. The basic criterion for the calculation of the peak current was the satisfaction of the apex electric field to field emission test conditions. A “hemisphere on a cylindrical post” emitter was shown to offer compelling advantages in both total emission current and threshold voltage values. The comparison of the effective values of the field enhancement factor and emission area with the apex field enhancement factor and formal emission area is carried out.