Improved performance of InGaN/GaN blue light‐emitting diodes with a SiO2/TiO2 Bragg reflector

InGaN/GaN blue light‐emitting diodes (LEDs) on sapphire substrates with a SiO2/TiO2 Bragg reflector were fabricated. The deposited SiO2/TiO2 Bragg reflectors exhibit a high reflectivity of up to nearly 96.9% at about 460 nm. When the InGaN/GaN LEDs with a SiO2/TiO2 Bragg reflectors were operated at a forward current of 20 mA at room temperature, the peak wavelength, the light output power, and the external quantum efficiency were measured to be 470 nm, 5.91 mW, and 11.21%, respectively. The light output power was as high as 15.33 mW at the forward current of 100 mA. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)