Luminescence spectra, efficiency, and color characteristics of white-light-emitting diodes based on p-n InGaN/GaN heterostructures with phosphor coatings

The luminescence spectra, efficiency, and color characteristics of white-light-emitting diodes fabricated from p-n InGaN/AlGaN/GaN blue-light-emitting heterostructures grown on SiC substrates and coated with yellow-green phosphors based on the rare-earth-doped yttrium-aluminum garnets were studied. The efficiency of blue-emitting diodes is as high as 22% at a current of 350 mA and a voltage of 3.3 V. The white-emitting diodes have luminous efficiency as high as 40 lm/W and luminous flux up to 50 lm at 350 mA.