Effects of a current-blocking layer with a metallic reflector on GaN-based light-emitting diodes 張鑑強、陳昭翰
E-mail: [email protected]
ABSTRACT
Light-emitting diodes (LEDs) are well-developed gradually in recent years; therefore, LED lighting has become the future trend in the lighting market. The major challenge is how to produce high-brightness white LEDs. The improvement of epitaxy has enhanced the brightness and efficiency significantly, and the technique of surface roughening also improved the light extraction efficiency.
However, the light beneath p-type electrode is absorbed by the electrode and the effect of current crowding reduces the efficiency, which is a critical issue in large-area LEDs because of the larger power losses. In order to solve the above problems, this thesis investigates the current-blocking layer with a metallic reflector for GaN-based LEDs with surface roughening. The results show that the optical output power is increased by 10.8% than the conventional surface-roughening LEDs.
Keywords : current-blocking layer、reflective layer、surface roughening Table of Contents
簽名頁 中文摘要...iii ABSTRACT...iv 誌謝...v 目錄...vii 圖 目錄...ix 表目錄...xi 第一章 緒論...1 1.1前言...1 1.2動 機...2 第二章 理論背景...5 2.1 p-n接面原理...5 2.2發光二極體的工作原 理...8 2.3電流阻障層理論...10 第三章 實驗方法與元件製程步驟...11 3.1實驗 架構...11 3.2蒸鍍系統...12 3.3感應式耦合電漿蝕刻機...15 3.4元件製作流 程...17 3.5元件製程步驟...22 第四章 結果與討論...29 4.1以氧電漿轟擊為電流 阻障層結構之元件光電特性...30 4.2以SiO2為電流阻障層結構之元件光電特性...32 4.3
以SiO2/Al/Cr為電流阻障層結構之元件光電特性...34 第五章 結論...35 參考文 獻...37
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