由於低功耗和高能效，藍光發光二極管已成為替代傳統光源的新解決方案。然而，面臨的最大挑戰之一是效率下降，即隨著注入功率的增加，效率下降。
本文研究了相空間填充效應和電流擁擠效應對LED效率下降的影響。它是通過三維數值模擬預測的。本文還提出了一種改進的休克-里德-里爾霍爾係數公式，用於代表載流子壽命行為。在本文中，InGaN / GaN發光二極管中的傳統電子阻擋層被大小與n-pad相同的圓形代替。使用圓形，集總的在外部有源區域中較高，而在焊盤下方的有源區域中較低。顯然，由於焊盤下方有源區域的大部分發射都被焊盤吸收，因此，具有圓形的LED將具有更高的外部量子效率。

Blue Light-Emitting Diodes has become a new solution to replace the traditional light source due to low power consumption and high energy efficiency. However, one of the most challenges facing is the efficiency droop which is efficiency degradation with higher injected power.
This dissertation investigates the effect of phase-space filling effect and current crowding effect on the efficiency droop of Light-Emitting Diodes. It is predicted by a three-dimensional numerical simulation. This dissertation also suggests a modified formulation of the Shockley-Reed-Hall coefficient, which is proposed to represent the SRH carrier lifetime behavior. In this dissertation, the traditional elec-tron electron-blocking layer in InGaN/GaN light-emitting diodes is re-placed by a circular shaped EBL the same size as the n-pad. With the circular electron-blocking layer, the lumped internal quantum efficiency is higher in the outer active region and lower in the active region under the n-pad. Since most emissions from the active region under the n-pad are absorbed by the n-pad, obviously, the Light-Emitting Diodes with the circular shaped electron blocking layer will have a higher external quantum efficiency.

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