606-nm InGaN Amber Micro-Light-Emitting Diodes With an On-Wafer External Quantum Efficiency of 0.56%

We demonstrated amber InGaN 47 x 47 mu m(2) micro-light-emitting diodes (mu LEDs) with the peak wavelength of 606 nm and full-width at maximum (FWHM) of 50 nm at 20 A/cm(2). The amber mu LEDs exhibited a 33-nm blue-shift of the peak wavelength and obtain broader FWHMs to approximately 56 nm at 5 to 100 A/cm(2). The peak on-wafer external quantum efficiency was 0.56% at 20 A/cm(2). The characteristic temperature was 50-80 K at 20 to 60 A/ cm(2) but increased to 120-140 K at 80 to 100 A/cm(2). The strong increase in the characteristic temperature from 60 to 80A/cm(2) couldmainly be attributed to the saturation of the Shockley-Read-Hall non-radiative recombination at high current densities.