Monte Carlo Modeling of Electron Transport and Capture Processes in AlGaAs/GaAs Multiple Quantum Well Infrared Photodetectors

Abstract

The results of an ensemble Monte Carlo (MC) particle modeling of vertical electron transport and capture processes in AlGaAs/GaAs multiple quantum well infrared photodetectors (QWIPs) are presented. The MC model employed takes into account features of the conduction band structure, the electron scattering parameters, and the interaction (reflection, transmission and capture) of free electrons with the QWs. It is shown that the heating of free electrons and their redistribution over the conduction band valleys under the influence of electric field play an essential role in both the transport processes and the capture into bound states in the QWs. The electron drift velocity and macroscopic capture parameter are calculated as functions of the structural parameters and applied electric field. The capture parameter exhibits a pronounced drop with increasing electric field due to a significant decrease of the fraction of electrons with energies less than the optical phonon energy.