Field emission in diode and triode vacuum nanostructures

To determine the emission characteristics of diode structures we use multiple images relative to the plane of the anode and cathode. And for triode structures such procedure was made for cathode-grid and grid-anode regions. In order to avoid singularity we move these planes from the boundary of atomic layers for a half-period of the lattice a. The tunnel current density have been calculated for diode and triode structures which are with a good agreement with experiment.