大面積陣列式氮化鎵發光二極體之研製與分析

Fabrication and analysis of large area array-type GaN-based light-emitting diodes

林志維(Chih-Wei Lin)

指導教授 ： 綦振瀛

國立中央大學/資訊電機學院/電機工程學系/碩士(2006年)

摘要

為了實現固態照明的夢想，我們朝向將元件面積大型化，並且操作在高電流下，以得到高光亮度輸出。本文章中我們提出以不同組合數目的小面積發光二極體，來建構出1×1 mm2 的大面積陣列式發光二極體，以改善傳統式大面積發光二極體之發光強度。
首先我們設計十字形p型金屬電極的陣列式發光二極體，發現在電激發光其光強度表現上，陣列式發光二極體確實能夠改善傳統式發光二極體之發光強度。但是在高電流注入下時，由於十字形p型金屬電極的設計因素，將導致發光強度呈現衰減現象。
為了改善上述光強度衰減的現象，我們改以設計圓形p型金屬電極，並且採用類似指叉式電極架構，將p、n型金屬電極置於元件左右兩側，以便探討電流傳導行為。在電激發光之光強度表現上，確實改善了之前十字形電極結構於高電流操作下造成光強度衰減的現象，並且陣列式發光二極體比起傳統指叉式發光二極體在光強度上也有提升。另外發現隨著小面積發光二極體的組合數目增加，可以得到更佳之電流均勻性，因此在發光強度以及熱效應上皆有好的表現。

關鍵字

陣列式 ； 發光二極體

並列摘要

In order to achieve solid-state lighting, the large-area light-emitting diodes are required to get more optical power at high operation current. In this study, we design and fabricate the array-type light-emitting diodes ( 1×1 mm2 ) to enhance optical power of the conventional light-emitting diodes.
Firstly, we design the array-type light-emitting diodes with cross-shaped p-pad. In room temperature electroluminescence measurements show that the array-type light-emitting diodes exhibit higher light intensity compared to the conventional broad-area light-emitting diodes, which is attributed to current spreading. In this study, the optical power decrease at high operation current due to lateral current crowding is caused by cross-shaped p-pad.
To improve optical power decrease at high operation current due to lateral current crowding near Mesa edge, we design array-type LED with circle-shaped p-pad. In electroluminescence measurements, the array-type light-emitting diodes as finger-type light-emitting diodes show higher light intensity compare to the conventional finger light-emitting diodes. Moreover, the array-type light-emitting diodes with more elements small light-emitting diodes have better current spreading and reduce current crowding.

並列關鍵字

light-emitting diodes ； array-type

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