我們使用銦預流處理來製造氮化銦鎵綠光發光二極體，並藉著實驗結果瞭解元件具備效率改進與對溫度變化穩定之特性。藉著這種銦預流處理技術，若使用效率方程式(rate equation)作實驗數據擬合，將獲得較高的輻射復合係數(B=3.34*10^-11 cm3*s-1 )，同時也對應內部量子效率(internal quantum efficiency, IQE)可以提昇9.2%，並且對注入載子來說漏電流路徑有顯著的減少；另一方面，若使用Shockley方程式針對變溫77K-400K之電壓電流特性做擬合，亦可以發現銦預流處理可以抑制缺陷所造成之漏電流路徑。更重要的是，銦預流處理技術明顯減緩綠光發光二極體之內部量子效率(external quantum efficiency, EQE)隨溫度變化與效率下降的現象。此種改善被認為是藉著銦預流處理在磊晶時優先形成銦富集點(In-rich-dot)，這些富含銦元素之量子點能有效抑制線差排會捕捉激子之特性，以及注入載子隨溫度提昇溢流出主動區之現象；此外，藉著模擬量子井中存在銦富集區域之結構，更驗證銦預留處理改善效率下降之可信度。

We present experimental results on the improved performance and high stable temperature characteristics of the InGaN green light-emitting diode (LED) with pre-trimethlyindium (pre-TMIn) flow treatment. By using pre-TMIn flow treatment, a relatively large radiative coefficient (B=3.34*10^-11 cm3*s-1 ) corresponding to a 9.2% enhancement in the internal quantum efficiency, as well as a significant reduction of leakage paths for injected carriers, was obtained. On the other hand, by using Shockley equation to fit the I-V curve from 77K to 400K, we find that pre-TMIn flow treatment can suppress the defect-assisted leakage path. Most important, the pre-TMIn flow treatment evidently reduces the dependence of the external quantum efficiency on temperature and efficiency droop of green LEDs. The improvement is thought to be attributable to the preferential formation of In-rich dots upon pre-TMIn flow treatment, which effectively suppresses the trapping of excitons by threading dislocations and the overflowing of injected carriers outside the active regions at elevated temperatures. In addition, by In-rich dots simulation in QWs, we can verify the reliability of our experiment results.

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