Conduction Mechanisms of Leakage Currents in InGaN/GaN-Based Light-Emitting Diodes

Local dot-like emissions in InGaN/GaN-based light-emitting diodes under both forward and reverse biases are investigated by carefully examining their locations and electroluminescence spectra. The effects of dot-like emissions on electrical and optical performances are also discussed. From the properties of the leakage-component dependence on electric field and temperature, the dominant reverse leakage mechanism is investigated as a function of bias from 100 to 400 K. It is concluded that the underlying mechanism of local dot-like emissions are related to threading dislocations under both reverse and forward biases.