臺灣博碩士論文加值系統

LED是近年來非常熱門的研究課題之一，許多文獻引用Shockley方程式來描述LED內部p-n junction處之電流-電壓變化，但由於LED之結構製程不斷改善，因此Shockley方程式可能已經不再適用於當今之LED。
本文參考其他文獻之實驗數據，推導出新的Diode方程式來描述p-n junction處之電流-電壓變化，並且更進一步推導出適用於具有多重量子井結構之LED上，並將其應用至LED模型內進行數值模擬。藉由數值模擬，可以得到LED內部之電位分佈，並且發現溫度對於作用在p-n junction處之電壓，會有很大的影響;除此之外， n電極以及電流阻擋層尺寸大小，對LED也會有很大影響。
根據本文之研究，可以得到在不同溫度以及不同n電極和電流阻擋層尺寸之下，LED之電流-電壓變化，希望能夠在LED之設計與應用上，提供許多幫助。

目錄.....................................................Ⅰ
圖目錄...................................................Ⅲ
致謝.....................................................Ⅳ
摘要 ....................................................Ⅴ
符號說明.................................................Ⅵ
第一章 序論...........................................1
1.1 前言..............................................1
1.2 文獻回顧..........................................2
1.3 研究目的..........................................5
第二章 理論分析......................................6
2.1 Diode方程式之推導................................6
2.2 具有多重量子井結構之Diode方程式..................7
2.3 新Diode方程式之應用..............................9
2.4 統御方程式......................................10
2.5 邊界條件........................................12
2.6 無因次化........................................13
第三章 數值方法.....................................16
3.1 網格系統........................................16
3.2 統御方程式之差分................................16
3.3 電場之計算方法..................................20
3.4 計算流程........................................20
第四章 結果與討論....................................22
4.1 模擬參數........................................22
4.2 網格設定........................................22
4.3 收斂標準........................................22
4.4 LED內部電場變化.................................23
4.5 不同溫度對LED之影響.............................24
4.6 不同尺寸n電極以及CBL影響........................26
第五章 結論..........................................27
參考文獻................................................28

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