Nitride-based LEDs fabricated on patterned sapphire substrates

Nitride-based blue LEDs prepared on both patterned and conventional sapphire substrates were both fabricated. It was found that although the EL peak positions of these two LEDs were about the same, the EL intensity of LED grown on patterned sapphire substrate was about 35% larger. The maximum output power of LED grown on patterned sapphire substrate also occurred at higher injection current. The reliability of LED grown on patterned sapphire substrate was also found to be better. There improvements could all be attributed to the reduced dislocation density in the LEDs grown on patterned sapphire substrates.