Experimental characterization of hot-electron-induced effects and light emission in heterostructure devices

Abstract
This paper reviews the most recent experimental results concerning the characterization of hot-electron effects and light emission in GaAs MESFETS, AlGaAs/GaAs and AlGaAs/InGaAs high electron mobility transistors (HEMTS), and AlGaAs/GaAs heterojunction bipolar transistors (HBTS). In MESFETS and HEMTS, light emission has been correlated with impact-ionization-induced gate current, providing insights into possible emission mechanisms. In HBTS, impact ionization can be evaluated by measuring the changes in the base current as a function of base-collector voltage. The measured multiplication factor correlates well with the results of a Monte Carlo simulation of the device, which also provides general microscopic details of the pre-avalanche regime.