Reducing the current crowding effect on nitride-based light-emitting diodes using modulated p-extension electrode thickness

In this paper, nitride-based light-emitting diodes (LEDs) with the modulated thickness of p-extension electrode were proposed and fabricated. The current crowding is always occurred in the end of p-extension electrode. Thus, the resistance of p-extension electrode will be increased by reducing its thickness to prevent current crowding. The modulated thickness of p-extension electrode can be employed to enhance the light output power and reduce overall operated temperature. Compared to the conventional LED, the enhancement in light output power is 13.9% at 150mA and the reduction in average operated temperature is about 14.6% at 80 mA. Regarding the characteristics of electrostatic discharge (ESD), the failure mode of new electrode design occurred on the terminal of thick p-extension electrode rather than current crowding region.