Semiconductor modeling for multi-layer, high field, photo-switch using sub-bandgap photons

High electric field geometries for high power, photo-conductive switches made possible by employing sub-bandgap photons and inter-bandgap dopants / defects are being investigated for compact pulse power systems. The high field, long absorption depth package reduces the required linear mode, optical closure energy and also reduces the conduction current density through the active material and at the contacts. In addition, the long absorption depth package increases the area available for thermal management and in concert with the reduced current density should increase the lifetime of the switch. This paper describes the semiconductor physics modeling of a multi-layer stack of GaAs wafers in a high electric field configuration. The model results of heavily doped n+ regions on electron injection, leakage current, and voltage hold off is discussed In addition, the modeling of the transverse injection of optical closure energy is discussed.