Investigation of Dominant Nonradiative Mechanisms as a Function of Current in InGaN/GaN Light-Emitting Diodes

Abstract

Dominant nonradiative recombination mechanisms as a function of nonradiative current were investigated in InGaN blue light-emitting diodes (LEDs). Each radiative and nonradiative current components were separated from the total current by using the information of the internal quantum efficiency (IQE), obtained from the temperature-dependent electroluminescence measurement. By analyzing voltage and light output power as functions of nonradiative current, we were able to understand that the dominant nonradiative mechanisms of the LEDs vary with the competing mechanisms of Shockley-Read-Hall or tunneling recombination at low current density to the carrier overflow at high current density, inducing the IQE droop. (c) 2013 The Japan Society of Applied Physics