High-efficiency 3.4-4.4 mu m light-emitting diodes based on a p-AlGaAsSb/n-InGaAsSb/n-AlGaAsSb heterostructure operating at room temperature

Light-emitting diode structures operating at room temperature were obtained based on a p-AlGaAsSb/n-InGaAsSb/n-AlGaAsSb heterostructure with high Al c ontent in the boundary layers formed on a p-GaSb(100) substrate. This struc ture ensures a threefold increase in the output radiant power and the exter nal quantum yield (similar to1%) as compared to the known InAsSb/InAsSbP he terostructure grown on an InAs substrate. A considerable increase in the pu lsed output radiant power is explained by a more effective confinement of n onequilibrium charge carriers in the active region and by a decrease in the nonradiative recombination level, which is achieved by creating an isoperi odic structure. (C) 2001 MAIK "Nauka / Interperiodica".