改變電極結構提升氮化鎵發光二極體亮度之研究

Changing the electrode structure to enhance the brightness GaN light-emitting diodes Study

馬玉濂(Yu-Lien Ma)

指導教授 ： 劉宗平

元智大學/電機通訊學院/光電工程學系/碩士(2013年)

https://doi.org/10.6838/YZU.2013.00239

摘要

傳統水平式結構之發光二極體，均勻的電流分佈(Current Spreading)對高功率發光二極體之發光效率、穩定度及元件，已經是不可或缺的一項重大指標之一，但除了均勻的電流分佈在亮度提升上面還是略嫌不足,由相關文獻可歸納出提升傳統水平式結構之發光二極體的發光效率方法為兩大類，提升外部量子效率與提升內部量子效率;多數利用側壁蝕刻製程與圖形化基板，光子晶體，ITO微結構，隱形雷射切割等等製程技術來提升亮度，本篇論文中主要探討製程面除了應用上述文獻回顧等等製程外，是否在亮度上有更進一步之技術與突破為本篇論文之重點。因此著手設計改變金屬結構主要以Al金屬層作為一反射鏡來提升發光二極體外部量子效率進而提升亮度;因此本篇論文主要的目的在於設計出不同的電極結構與厚度探討不同結構發光二極體之光電特性，與亮度間之變化關係。

關鍵字

反射電極

並列摘要

In terms of traditional horizontal structure of light emitting diode (LED), a uniform current distribution (Current Spreading) for high light-emitting efficiency, stability and components is already a major indicator of the technology. However, the level of the effects of uniform current distribution on the brightness increase is limited. Relevant literatures can be summarized into two categories to improve the traditional horizontal structures light-emitting efficiency. Enhancing the external quantum efficiency and improve the internal quantum efficiency; using sidewall etch and graphical substrate, photonic crystals, ITO microstructure, invisible laser cutting process technology, etc. to enhance the brightness. This paper focuses on the processing aspect of the technology along with application from literature reviews to examine whether there are possible improvements in the brightness. Therefore, this paper suggests to modify the metal structure using A1 metals as a layer of reflector to enhance the light-emitting diode external quantum efficiency and thus to increase the brightness. In short, the objective is to design a different electrode structure and thickness to explore the relationships between the optical properties of the body and changes in the brightness.

並列關鍵字

pad mirror

參考文獻

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