Enhanced light extraction of GaN-based light-emitting diodes by using textured n -type GaN layers

The authors report on the enhancement of the light extraction efficiency of GaN-based light-emitting diodes (LEDs) via the texturing of n -type layers. Compared with standard LEDs, LED fabricated with the textured n -type layers produced a significant improvement in the output power, depending on the reflectivity of the n electrode, the etch-pit size, and the chip dimension. The textured LEDs were found to yield the output power enhancement as high as 54%. However, it was also found that the electrical property of the textured LEDs can be degraded when the size of the etch pits is too large, indicating that a well-controlled texturing process is required for the realization of high-efficiency LEDs.