Study on Strain Compensation for Multiple-Quantum Well in Infrared Light-Emitting Diode Using the InGaP Strain Barrier.

Strain compensation for multiple-quantum wells (MQWs) relative to the efficiency improvement of infrared light-emitting diodes (IR-LEDs) was investigated through the use of an InxGa1-xP strain barrier. The InxGa1-xP barrier, which was inserted between the n-confinement and active regions, developed for the reduction of lattice-mismatched strains in GaAs/AlGaAs and InGaAs/GaAs MQWs. Through photoluminescence, improved intensity was displayed in InGaAs/GaAs MQWs having InxGa1-xP strain barriers, with a significant increase in the intensity observed at the In0.47GaP strain barrier. This result is attributed to strain compensation between the In0.47GaP tensile strain barrier used and the In0.07GaAs compressive strain in MQWs. Through results based on InGaAs/GaAs MQWs, the highest output power of 6 mW was obtained at the In0.47GaP strain barrier, which shows a relative increase of almost 20% as compared to conventional MQWs.