LONG-WAVELENGTH INAS INGASB INFRARED DETECTORS - OPTIMIZATION OF CARRIER LIFETIMES/

The performance characteristics of type-II InAs/InxGa1-xSb superlattic es for long and very long-wave infrared detection are discussed. This system promises benefits in this wavelength range over conventional te chnology based on Hg1-xCdxTe, in part because of suppressed band-to-ba nd Auger recombination rates which lead to improved values of detectiv ity. The formalism for calculating Auger rates in superlattices is dev eloped and the physical origin of Auger suppression in these systems i s discussed. Accurate K . p band structures are used to obtain radiati ve, electron-electron, hole-hole, and band-to-band Auger rules, as wel l as shallow trap level assisted Auger recombination rates for photodi odes. Theoretical limits for high temperature operation of ideal photo voltaic detectors are presented and compared with HgCdTe. (C) 1995 Ame rican Institute of Physics.