Two-dimensional domain dynamics in a planar Schottky-gate Gunn-effect device

A two-dimensional computer-aided analysis on the domain dynamics in a planar Gunn device with a Schottky-barrier gate has been performed both for the repeatedly nucleated-domain mode (continuous operation) and for the triggered single-domain mode (triggered operation). The difference in the domain behavior between planar devices with coplanar ohmic electrodes and with parallel ohmic electrodes leads to a conclusion that the edge effect caused by the current crowding at the anode deteriorates the switching speed associated with the domain formation and extinction on the planar Gunn device with the coplanar electrodes. It is shown how a domain is nucleated under the gate, travels to the anode, and disappears there in the presence of the two-dimensional effects. The mechanism of the Schottky-gate triggering on the reverse-biased condition which differs substantially from the FET model has been made clear.