Performance of AlGaN/InGaN Multiple Quantum Well LEDs Simulated Using COMSOL

• Main Author: Badrul Hisham, Nor Aqilah Amira
• Format: Final Year Project
• Language: English
• Published: IRC 2016
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://utpedia.utp.edu.my/17202/1/DIssertation_18596.pdf; http://utpedia.utp.edu.my/17202/

In this work, efficiency droop phenomena which is one of the most significant challenges faced by GaN-based light emitting diodes (LEDs) is investigated in both single quantum well (SQW) and multiple quantum well (MQW) LEDs. There are many mechanisms which are proposed to be responsible for efficiency droop but the focus of this work is only on electron leakage and current crowding. In order to address these phenomena, SQW and MQW GaN-based LEDs is simulated using COMSOL Multiphysics and the performance of the LEDs is analyzed by plotting the graph of internal quantum efficiency (IQE) against current density. Based on the graph, it is found out that the efficiency droop worsens when the number of quantum well (QW) increases. From this observation, it is proposed to introduce graphene-based transparent conductive electrodes (TCEs) onto the LEDs surface. Graphene monolayer will spread the current away from the metal pads and hence reduce the current crowding problem and improve the efficiency droop.