Light-emitting AlGaAs/GaAs diodes based on ingaas strain-compensated quantum wells with minimized internal losses OF 940 nm radiation absorption

Abstract

IR light-emitting diodes based on InGaAs/AlGaAs multiple quantum wells and AlxGa1–xAsyP1–y-layers that compensate stresses in the active region have been developed. The optical losses caused by absorption of radiation generated by the active region (λ = 940 nm) were studied at different doping levels of n-GaAs substrates. It has been shown that reducing the donor doping level from 4 × 1018 to 5 × × 1017 cm–3 gives an increase in the quantum efficiency of LEDs by ~ 30%. A technology that eliminates optical losses caused by absorption during radiation output has been developed. By removing the growth substrate and transferring the device structure to a carrier substrate with the formation of a rear metal reflector, LEDs were created that demonstrate a twofold increase in external quantum efficiency and efficiency (~ 40%) compared to the technology of outputting radiation through an n-GaAs substrate.