Microplasma breakdown of InGaN/GaN heterostructures in high-power light-emitting diodes

Microplasma breakdown luminescence of InGaN/GaN heterostructures in different types of high-power light emitting diodes is studied. It is shown that the spectrum of the breakdown luminescence, the luminescence onset voltage, the current in the fi rst microplasma, and the number of microplasmas for a fi xed voltage all correlate with the density of critical extended defects, the luminous fl ux, and the uniformity of current fl ow, and are determined by the type of substrate (Si, SiC, Al2O3).