Current Crowding Effects on the Thermal Performance of AlGaN/GaN Light Emitting Diodes

Today, ultraviolet (UV) and visible light-emitting diodes (LED’s) are being vastly used in a variety of application areas, such as automotive, construction and healthcare. One of the most important parameters to consider in LED design is the non-uniform heat generation during the operation of the device since it causes important drawbacks such as performance degradation or ultimately device failure. Coupled electrothermal modelling approaches are useful to understand the thermal behavior of devices and predict the highest temperatures in active device layers where physical measurements are either difficult or not possible. For this purpose, we simulated a LED device under different operation conditions by employing an electrical study via the semiconductor module of COMSOL Multiphysics. Total heat generation from joule heating and recombination heating is calculated and their effects on temperature distribution is observed for each case. The effect of current crowding on the thermal and electrical performance of devices are investigated using this technique.