Electrostatic discharge influence on carrier dynamics and reliability characteristics of GaN-based blue light-emitting diodes

We have investigated electrostatic discharge (ESD) damage influence on the carrier dynamics and the reliability characteristics by using current-voltage (I-V), capacitance-voltage-temperature (C-V-T), and electroluminescence (EL) data. Measurements show that the ESD-damaged LED yields on increase in the generation/recombination current and ideality factor more than those of the normal LED. It means that the generation of the 2^nd defect concentration occurs as a result of electrostatic discharge damage. The capacitance accumulation at deep-level, around 2 V was found out the ESD-damaged LED rather than the normal LED. In addition, the shallow-level ionization is more dominant for the normal LED without ESD, while the deep-level ionization is more dominant for the ESD-damaged LED. These results mean that the ESD failure mechanisms described in terms of shallow level/deep level carrier dynamics, generation of 2^nd deep level defects, and non-radiative/radiative recombination.