由於地球暖化現象日趨嚴重，綠色科技產品在近幾年發展越來越快速，發光二極體即為眾多綠色科技產品之一。發光二極體具有高亮度、壽命長、省電及低污染等優點。在環保意識抬頭的今日，使用對環境汙染較小且消耗功率較低的發光二極體，取代傳統的白熾燈泡及日光燈勢必是未來的趨勢。然而，發光二極體的光電轉換效率仍然過低，大部份的輸入能量皆以熱能的形式輸出，造成晶片接面溫度上升，此現象將導致晶片發光強度降低、減少使用壽命。因此，對發光二極體進行有效的熱能管理將是發光二極體產業共同努力及研究的目標。
本研究根據熱傳導基本理論、半導體電性概念，使用有限單元分析軟體ANSYS®建立高功率發光二極體黏著於鋁製散熱鰭片之結構，搭配William與van de Pol等人提出自然熱對流理論帶入邊界條件進行模擬分析，並輔以順向偏壓法間接量測晶片接面溫度，驗證模擬結果的正確性，其結果顯示誤差皆在5%之內。此外，以此有限單元三維模型為基礎，進行新型發光二極體封裝結構(Chip-in-substrate type LED Package)的設計，模擬內部結構的熱傳物理行為及進行參數化分析。雖然新型發光二極體封裝結構在散熱效能上僅有微幅的進步，但可批量製造的特性，足以減少生產製造成本，增加此結構的競爭力。
在光衰壽命測試(Life Test)中，本研究使用不同幾何形狀、材質的散熱鰭片作為發光二極體散熱之用，以產生不同的晶片接面溫度，進行光衰壽命測試。將實驗結果繪製成相對發光強度與時間之關係曲線圖，探討晶片接面溫度和光衰形式的關係，並找出造成光衰的破壞機制，以改進現有發光二極體之問題。
在本研究中，以有限單元分析軟體ANSYS®模擬發光二極體之散熱特性，可快速的設計新型封裝結構並提出有效降低晶片接面溫度的方法，以提升發光二極體的發光強度與使用壽命，使發光二極體作為日常照明設備將指日可待。

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