Computational Modelling of Surface Effects in InGaN/GaN Quantum Disk Nano Wire LEDs

摘要

One focus of the current research on light emitting diodes (LEDs) for lighting are nano structured devices which are expected to improve the efficiency and reduce the production costs. Structuring on the sub-micrometer scale increases the surface area with respect to the active volume so that surface effects have a large impact on the device performance. The physics of these devices is not fully transparent to characterization making an experimental analysis tedious. In this work we demonstrate the computational modelling of nano structured LEDs to complement the experiment. The implementation of the simulation model considers surface effects using a numerically accurate true area box method discretization. The derived surface models are applied to the self-consistent simulation of nano wire quantum disk light emitting diodes. By the computational study we demonstrate that the surface physical effects are critical for the performance of nano structured optoelectronic devices and that a low efficiency may be fully attributed to surface recombination.