Investigation of carrier spill-over in InGaN-based light-emitting diodes by temperature dependences of resonant photoluminescence and open-circuit voltage

Abstract

In InGaN-based light-emitting diodes (LEDs), carrier leakage to the outside of the active quantum wells (QWs) has been considered as one of the dominant carrier loss mechanisms at high current densities. In order to verify the carrier spill-over phenomenon, we compared the electroluminescence (EL) efficiency, the resonant photoluminescence (PL) efficiency, and the open-circuit voltage as functions of current, temperature, and excitation laser power. Very similar tendencies were experimentally observed among the three physical quantities, which implied that carriers were spilt over out of the QWs even in the resonant PL experiment.