探討電流聚集效應和出光對深紫外發光二極體效率影響之數值模擬與研究

Numerical study of the current spreading and light extraction in deep UV light emitting diode

陳欣卉(Xinhui Chen)

指導教授 ： 吳育任

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.01683

摘要

無資料

關鍵字

紫外發光二極體 ； 氮化鋁鎵 ； 電流分佈 ； 出光效率 ； 超晶格

並列摘要

UVLEDs are in strong demands in recent years because of their special applications in industry and medicine. However, comparing with the commercial InGaN LEDs, the overall efficiency in UVLEDs is extremely low especially in UVC spectrum. The main reasons are found to be: (a) High defect densities in the AlGaN layer that result in low IQE; (b) The activation energy of Mg doped p-AlGaN layer is relatively high, which results in the poor hole injection and the increase of resistance; (c) Large absorption rate of the conventional p-GaN contact, which makes the light extraction efficiency much lower. To improve these issues, we focus on improving the current spreading and light extraction by considering different structures or different contact layers with Poisson and drift-diffusion solver to see how they influence the efficiency in UVLEDs. Moreover, we modeled a series of AlGaN superlattice structures to confirm that such a structure has a great potential of being used as the p-contact layer instead of p-GaN contact in UVLEDs. Finally, we discuss about the AlGaN UVB LEDs to find what the more important factor to limit their efficiency is.

並列關鍵字

Ultraviolet light-emitting-diode ； AlGaN ； Current spreading ； Light extraction ； Superlattice

參考文獻

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