Various size images mapping technique to analyze trap-assisted non-radiative recombination mechanism using Cathodo- and Electro- Luminescences measurement in GaN-based LEDs

We have investigated the non-radiative recombination of GaN-based light-emitting diodes (LEDs) using electroluminescence (EL) and cathdoluminescence (CL) techniques. Comparing between EL and CL measurements, we can map the defects causing non-radiative recombination centers. At first, same size mapping techniques of these two measurements show defect-assisted non-radiative recombination. And enlarged CL images give more detail contents about this mechanism. It is concluded that the image mapping of EL and CL in GaN have a strong correlation between the two techniques, and this result shows that non-radiative recombinations are mainly affected by defects of GaN LEDs.