Exploring an InGaN Micro-LED structure for optimum IQE operating on low current condition through simulation study

Light-emitting diodes (LEDs) are key components in display applications. The quantum efficiency of GaN/InGaN LEDs has been enhanced, leading to advancements in indoor and outdoor RGB LED display applications. White LED backlights are commonly used in displays due to the increased efficiency of InGaN LEDs. Despite efficiency, lifespan and image retention issues, OLED displays are utilized in high-end mobile phones to meet market expectations for screen response time and color saturation. Micro-LED RGB full-color displays have the potential to dominate the next-generation display market, driven by the increasing demands for resolution, power consumption and response time. Micro-LEDs are becoming smaller, reaching sizes of 50 μm or even smaller, to meet the high-resolution requirements of displays. They offer higher contrast, brightness and faster response speeds. This research utilizes numerical simulations to develop a model for radiative and nonradiative recombination in InGaN semiconductor materials. The aim is to investigate the internal quantum efficiency (IQE) of various chip sizes, quantum well counts, well thicknesses and electron block layers under low current densities. The research reveals that the optimal structure is a single quantum well with an electron block layer (EBL), which can increase IQE from 53.85% to 80.9% at 0.01 A/cm² under low current density conditions, with a decrease in the number of quantum wells to one. The IQE efficiency improvement is 27.05%.