AlAsSb

Applications

AlAsSb is occasionally employed as a wide-bandgap barrier layer in InAsSb-based infrared barrier photodetectors. In these devices, a thin layer of AlAsSb is grown between doped, smaller-bandgap InAsSb layers. These device geometries are frequently referred to as "nbn" or "nbp" photodetectors, indicating a sequence of an n-doped layer, followed by a barrier layer, followed by an n- or p-doped layer. A large discontinuity is introduced into the conduction band minimum by the AlAsSb barrier layer, which restricts the flow of electrons (but not holes) through the photodetector in a manner that reduces the photodetector's dark current and improves its noise characteristics.