高品質氮化鋁模板應用於氮化物發光二極體光電特性之研究

Investigation of Nitride-Based Light-Emitting Diodes With High quality AlN Template

丁宏洋(Hung-Yang Ting)

指導教授 ： 郭政煌

國立交通大學/光電學院/照明與能源光電研究所/碩士(2020年)

摘要

本論文利用高溫退火系統對物理氣象沉積製備的氮化鋁薄膜進行退火，在1650℃常壓下改變退火時間進行退火實驗，之後成長藍光發光二極體及紫外光發光二極體結構，接著利用黃光微影製程製作出藍光發光二極體及紫外光發光二極體，進行光電特性的分析並探討物理氣象沉積製備的氮化鋁薄膜在不同退火時間下對藍光發光二極體及紫外光發光二極體光電特性的影響。
由藍光發光二極體及紫外光發光二極體發光機制的差異及缺陷密度的影響可知，在發光層銦比例較高的藍光發光二極體會形成較深的局域態(localized states)，使載子較不容易溢流(overflow)，因此受缺陷密度影響較小，而紫外光發光二極體由於發光層銦比例很低使得局域態很少，造成載子容易受缺陷侷限導致內部量子效率下降，因此缺陷密度對其影響很大。由實驗結果可知，在氮化鋁薄膜退火2小時情況下的藍光發光二極體光輸出功率提升了10.93%，而紫外光發光二極體光輸出功率提升了76.97%，在發光層銦比例較低的紫外光發光二極體發光效率提升的效果確實較發光層銦比例高的藍光發光二極體明顯。

關鍵字

氮化鋁 ； 氮化物發光二極體

並列摘要

In this study, thermal annealing system is used to anneal the aluminum nitride(AlN) film prepared by physical vapor deposition(PVD) and the annealing temperature is 1650℃ under atmosphere. Subsequently, blue light-emitting(LED) device and ultraviolet(UV) LED device are fabricated using a photolithography process. The results are analyzed, including influences of PVD-AlN under various annealing times and photoelectric characteristics of blue LED and UV LED were prepared on various annealing times PVD-AlN template.
The emission mechanism of blue LED and UV LED was totally different. It’s well known that the blue LED with a higher proportion of indium in the active layer will form a deeper localized state, making the carriers less likely to overflow. Therefore, blue LED are less affected by the defect density. In contrast, UV LED with extremely lower proportion of indium in the active layer will form low localized state density. The carriers of UV LED can be easily trapped by dislocation. Therefore, UV LED are considerably influenced by defect density. The result was shown that the light output power of the blue and ultraviolet LED by using annealing the PVD-AlN for 2 hours were increased by 10.93% and 76.97%,respectively. The light output power improvement of ultraviolet LED with a lower proportion of indium in the active layer is more significant than that of blue LED with a higher proportion of indium in the active layer.

並列關鍵字

AlN Template ； Nitride-Based LED

參考文獻

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