Role of surface defects in the efficiency degradation of GaInN-based green LEDs

The role and effect of surface defects (SDs) on the efficiency degradation of GaInN-based green LEDs was investigated. Two types of green LED samples having the same structure were prepared; an additional underlying layer was introduced in one sample to artificially reduce SDs in the multiple quantum well active region. Then, various characteristics were analyzed for both samples. Based on these analyses, schematic models including those of SD dynamics during growth and potential fluctuation induced by SDs in green LEDs were proposed. Results show that SDs play a crucial role in efficiency degradation. (C) 2019 The Japan Society of Applied Physics.