Early Degradation of GaN-based Power LED under Electrical Stresses

InGaN/GaN-based blue and green light emitting diodes(LEDs) were under an aging with DC current of 900 mA at room temperature.The tunneling current was minimum after 24 h and 6 h for blue and green LED due to the thermal annealing effect which reduced defects.At the same time,the leakage current was minimum and light output was maximum.Then the leakage current increased and luminous flux reduced for green LED.The thermal annealing effect and defect generation were proposed as positive and negative accelerating factor,respectively.The negative accelerating factor of green LED increased quicker than that of blue LED and green LED decreased seriously.The results of analysis have a certain reference value for the improve of GaN LED.