Color stability, wave function overlap and leakage currents in InGaN-based LED structures: The role of the substrate orientation

We present a theoretical study of the performance of InGaN-based light-emitting diodes in terms of built-in fields, wave function overlap, emission wavelength shift with current density and leakage currents. We analyze polar (c-plane), semipolar ((11-22), (10-1-3), (20-21) and (20-2-1)) and non-polar systems. Compared with the c-plane, the semipolar planes show substantial improvements. An exceptionally high wave function overlap is expected for the (10-1-3) orientation, making it an attractive alternative to non-polar devices with low InN content. The (11-22) and (20-21) systems give rise to a natural carrier blocking layer, leading to significantly reduced leakage currents.