High-Brightness InGaN–GaN Power Flip-Chip LEDs

We report the fabrication of InGaN–GaN power flip-chip (FC) light-emitting diodes (LEDs) with a roughened sapphire backside surface prepared by grinding. It was found that we can increase output power of the FC LED by about 35% by roughening the backside surface of the sapphire substrate. The reliability of the proposed device was also better, as compared to power FC LEDs with a conventional flat sapphire backside surface.