Nitride-based LEDs with an insulating SiO2 layer underneath p-pad electrodes

We proposed a simple method to reduce the current crowding effect of nitride-based light emitting diodes (LEDs) without extra dry etching and refill. It was found that we can achieve much better current spreading by inserting an insulating SiO 2 layer between the epitaxial layer and the p-pad electrode. It was also found that we can enhance light output intensity by 22%. Furthermore, it was found that 20 mA forward voltage only increased slightly from 3.32 to 3.37 V with the insertion of the SiO 2 layer. The reliability of the proposed LED is also good.

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