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研究生: 陳正健
Cheng-Chien Chen
論文名稱: 白光LED封裝效率與可靠性分析之研究
Study of Package Efficiency and Reliability of Phosphor-converted White LED
指導教授: 孫慶成
Ching-Cherng Sun
口試委員:
學位類別: 博士
Doctor
系所名稱: 理學院 - 光電科學與工程學系
Department of Optics and Photonics
論文出版年: 2012
畢業學年度: 101
語文別: 中文
論文頁數: 171
中文關鍵詞: 發光二極體LED封裝效率LED光衰螢光粉粒子數螢光粉模型
外文關鍵詞: LED, LED package efficiency, LED lighting decay, Phosphor particle number, Phosphor model
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  • 在本論文中我們探討並分析白光 LED 之封裝效率並提出一種快速檢測 LED 燈具壽命之方法。首先,我們利用已建構之YAG螢光粉模型在相同的相關色溫之條件下,分析六種封裝架構在封裝效率上的差異,並討論其封裝效率差異的原因,再探討改變散熱基板反射率與晶粒對於藍光的吸收率等參數對封裝效率的變化;並搭配實際封裝與量測進行驗證,提出封裝效率最高之封裝體與討論實際封裝體之損耗來源。
    接著我們提出螢光粉粒子數用以整合螢光粉層中之濃度與厚度並以此討論白光 LED 封裝在光學與色彩上的表現,藉此簡化在螢光粉封裝時的參數,並驗證在相同相關色溫中,分析兩種不同封裝架構之不同濃度厚度在發光效率上的差別。
    最後,我們提出一套能供產線使用且能快速檢測 LED 燈具壽命之架構,能大幅降低檢測之時間與提升量測上的便利性;在架構中我們先利用加速老化的方式建立 LED 之結溫對於燈具壽命之關係,再取得不同光衰與結溫溫差的對應方程式與決定初始照度值的量測方式而得可利用光衰快速推算 LED 燈具壽命之模型,並以實驗進行驗證與討論實驗量測之誤差,且針對實際產線應用上提出建議之光衰值。


    In this thesis, we analyzed the package efficiency of white light LEDs and proposed a method to evaluate the lifetime of LED lamps rapidly. Based on the well-constructed YAG phosphor optical model, we analyzed the difference of package efficiency with six different package structures under the same correlated color temperature. And we discussed the influence of the package loss by changing the reflectivity of the substrate and the absorption coefficient of the die. Then we verified the experimental results with simulation data and investigated the difference of package loss with experimental package.
    In order to figure out the effect of different thickness and concentration of phosphors on the performance of LEDs, we demonstrated a method to calculate the phosphor particle numbers and studied the relationship among phosphor particle numbers, light output and correlated color temperature of LEDs under remote package type and dispensing package type. And we can simplify the parameter of LED package by using phosphor particle numbers.
    Finally, we proposed a method to estimate the lifetime of LED lamps quickly and this method can reduce the time for detection. We applied the accelerated test method to build up the relationship among the junction temperature of LEDs and lifetime, then we established the function of lighting decay and difference of junction temperature, we also decided the method to get the initial points. Finally, we combined all those methods to evaluate the lifetime of LEDs lamps rapidly and verified the results with the experimental data. And we suggested a value of lighting decay for the practical application.

    摘要 i Abstract ii 誌謝 iv 目錄 viii 圖目錄 xii 表目錄 xx 第一章 緒論 1 1.1 照明發展歷程 1 1.2 白光 LED 發展與背景 3 1.3 研究動機與目的 7 1.4 論文大綱 11 第二章 基本原理 12 2.1 引言 12 2.2 LED 發光原理 12 2.3 螢光粉發光原理 17 2.4 白光 LED 能量轉換過程 21 2.5 封裝流程與種類 23 2.5.1 功率型白光 LED 封裝流程 23 2.5.2 傳統指示型 LED 封裝 24 2.5.3 表面黏貼型 LED 封裝 26 2.5.4 功率型白光 LED 封裝 27 2.6 熱阻與結溫之介紹 29 第三章 白光 LED 封裝之光學效率分析 33 3.1 前言 33 3.2 封裝效率之定義 34 3.3 YAG 螢光粉模型 36 3.3.1 螢光粉模型之文獻回顧 36 3.3.2 YAG 螢光粉模型之介紹 37 3.4 不同白光 LED 封裝效率之分析 41 3.4.1 不同白光 LED 封裝架構之建立 41 3.4.2 不同白光 LED 封裝效率之分析 44 3.4.2.1 不同散熱基板反射率之比較 46 3.4.2.2 不同晶粒對藍光的吸收係數之比較 56 3.5 實驗驗證與分析 61 3.5.1 實驗架構 61 3.5.2 實驗藍光出光之計算 62 3.5.3 實驗封裝 65 第四章 白光 LED 中螢光粉粒子數對於光學表現之研究 73 4.1 引言 73 4.2 實驗架構 73 4.3 螢光粉粒子數之計算方式 77 4.4 探討與分析 81 4.5 螢光粉濃度與厚度分析 90 第五章 利用 LED 光衰進行快速壽命檢測之架構 94 5.1 前言 94 5.2 文獻回顧與研究動機 94 5.3 不同電流之壽命分析 104 5.4 不同環境溫度下之 LED 光衰的量測架構 108 5.5 LED 光衰與 Tj 之討論 110 5.6 架構驗證與誤差討論 121 第六章 結論 128 參考文獻 132 中英文名詞對照表 139 Paper list 146

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