SELF-CONSISTENT MODEL FOR QUANTUM-WELL INFRARED PHOTODETECTORS

We present the results of a new model for the simulation of quantum we ll infrared photodetectors (QWIPs) both in dark conditions and under i llumination. This model takes into account the elementary mechanisms i nvolved in the detection process (injection at the contacts, balance b etween capture and emission in each well) in a self-consistent way. Th e main feature emerging from the model is the redistribution of the el ectric field along the structure in order to maintain current conserva tion. The calculated dark current, electrical noise, responsivity, and detectivity of different QWIP structures are compared with experiment al measurements and the agreement is found to be fairly good. This mod el may be considered as a step toward more powerful simulation tools f or QWIPs. (C) 1995 American Institute of Physics.