High-Brightness InGaN Blue, Green and Yellow Light-Emitting Diodes with Quantum Well Structures

TLDR

Blue, green and yellow III‑V nitride LEDs with quantum‑well structures were grown on sapphire by metal‑organic chemical vapor deposition. The LEDs exhibited peak wavelengths of 525 nm (green) and 590 nm (yellow) with FWHMs of 45 nm and 90 nm, respectively; at 20 mA the green devices delivered 1 mW, 2.1 % EQE, and 4 cd—about 40 × brighter than conventional GaP LEDs—while the yellow devices produced 0.5 mW, and overall output power dropped markedly from blue to yellow.

Abstract

High-brightness blue, green and yellow light-emitting diodes (LEDs) with quantum well structures based on III-V nitrides were grown by metalorganic chemical vapor deposition on sapphire substrates. The typical green LEDs had a peak wavelength of 525 nm and full width at half-maximum (FWHM) of 45 nm. The output power, the external quantum efficiency and the luminous intensity of green LEDs at a forward current of 20 mA were 1 mW, 2.1% and 4 cd, respectively. The luminous intensity of green LEDs (4 cd) was about 40 times higher than that of conventional green GaP LEDs (0.1 cd). Typical yellow LEDs had a peak wavelength of 590 nm and FWHM of 90 nm. The output power of yellow LEDs was 0.5 mW at 20 mA. When the emission wavelength of III-V nitride LEDs with quantum well structures increased from the region of blue to yellow, the output power decreased dramatically.