Simulation of Carrier Injection Pathways in Axial GaN Nanowire MicroLEDs

Abstract Micro Light‐Emitting Diodes (MicroLEDs) are expected to penetrate the display market and allow for the development of augmented reality (AR) or virtual reality (VR) technologies. InGaN/GaN nanowires are very promising for these applications, thanks to their high luminescence and emission directivity. However, there is still room for significant improvement of the efficiency of these 3D nanostructures. This study presents a numerical simulation of multiple quantum well (MQW) nanowires in Light‐Emitting Diodes (LEDs). Using a Poisson‐drift‐diffusion solver, the tuning of the injection efficiency for multiple geometries and material variations will be presented. It is found that the injection of holes through the multiple planes of nanowires always follows a lateral injection through the semi‐polar planes into polar quantum wells, that needs to be optimized to ensure radiative recombination in the first quantum wells. The ratio of polar/semi‐polar plane quantum wells length is a key factor in the design of nanowires, and the Wall‐Plug Efficiency (WPE) significantly varies with the size of semi‐polar quantum wells. Furthermore, the impact of degraded recombination area at the top and bottom of the nanowire confirms that a careful choice in the quantum well number must be carried out. The design of optimal and efficient InGaN/GaN nanowires, hence, reveals complex trade‐offs, adjustable through controlled epitaxial growth.