Effect of current spreading on the efficiency droop of InGaN light-emitting diodes
1Department of Physics, Inha University, 253 Yonghyeon-dong, Incheon 402-751, South Korea.
Abstract:
We investigate the effects of current spreading on the efficiency droop of InGaN blue light-emitting diodes with lateral injection geometry based on numerical simulation. Current crowding near the mesa edge and the decrease in the current spreading length with current density are shown to cause significant efficiency droop. It is found that the efficiency droop can be reduced considerably as the uniformity of current spreading is improved by increasing the resistivity of the p-type current spreading layer or decreasing the sheet resistance of the n-GaN layer. The droop reduction is well interpreted by the uniformity of carrier distribution in the plane of quantum wells.
Related Concept Videos
Biasing of P-N Junction
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
Diode: Reverse bias
Small-signal Diode Model
Diode: Forward bias
The behavior of a diode in forward bias...
Impedance Combination
P-N junction

