High-Power AlGaInN LEDs Operated Under High Pulsed Current Density (up to 7 kA/cm2)

Current dependences efficiency, emission spectra, rise and fall time of 3 different design high-power blue LEDs have been investigated under extremely high pump current density up to 7 kA/cm2 and pulse duration 100 ns. Analysis of the pulse-behavior of the LEDs reveals revealed that the main droop in efficiency and a change in the spectrum occurs up to current densities of ~2kA/cm2 and have a non-thermal character. The rise and fall time are more than 20 ns due to the high capacitance of the LEDs.