Scaling and optimization of chip design for mini- and micro-LEDs

Miniaturization of LED chip dimensions raises up numerous exploitation problems. At high current densities, both thermal droop and non-thermal droop caused by Auger recombination reduce the LED efficiency. At low current densities, a similar reduction originates from carrier surface recombination at the sidewalls of the chip. In addition, size-dependent current crowding and device self-heating interfere the main LED characteristics. Therefore, careful physics-based optimization of the LED design is necessary to make feasible development of the efficient mini- and micro-LEDs. Coupled electrical-thermal-optical simulations are applied to identify key mechanisms affecting the device performance, which is dependent on the chip size. The paper shows how modeling and simulation can serve for better understanding of mini- and micro-LED operation and for optimization of their designs and operation conditions.