本論文針對晶粒級覆晶式封裝白光LED進行最佳化分析，且根據不同封裝形式，提出八種可在製程上實現之封裝結構，並針對其內部螢光粉及矽膠結構與外部封裝尺寸進行優化，探討影響光萃取效率及空間色彩分佈之主要原因，同時考慮實際上散熱鰭片表面之漫反射特性，確保模擬結果更接近於現實。
從模擬結果中，得知主要影響空間色彩分佈之原因與螢光粉結構及封裝外部比例有極大關係。例如當Type I與Type II封裝體尺寸比例為1.1至1.3時，可獲得最佳的空間色彩分佈，正負80度內所對應之 皆小於0.004，且當封裝體大於晶粒體積25倍以上時，有最佳的光萃取效率結果。而主要影響光萃取效率的封裝反射表面為藍光覆晶晶片底部的反射層，以及封裝體底部之白漆反射層，若能有效提升上述兩者之反射率，將提升光萃取效率10至20%，且不影響空間色彩分佈之結果。最後，為了進一步提升空間色彩分佈之均勻性，分析摻雜不同濃度的奈米粉末粒子於封裝體中之結果，當摻雜濃度5%的奈米粉末粒子於Type I之螢光粉結構中，可使整體 改善至0.00064，且正負80度內的 分佈皆小於0.001。

This paper analyze light extraction efficiency (LEE) and color spatial uniformity (CSU) for flip-chip white light-emitting diodes with chip scale packaging. Depends on the type of package, we propose eight different structures which can be realized. Furthermore, the internal phosphor and silicone structures as well as the external packaging size is optimized. At the same time, the root cause of affect LEE and CSU is discussed. In addition, to ensure the simulation results is close to reality, this study take into account the diffuse reflection characteristics on the surface of the heat sink.

According to the simulation results, we can figure out that the main impact of CSU is phosphor structure and scale of package size. For example, when the height-width-ratio (HWR) of Type I and Type II is from 1.1 to 1.3, the CSU will be reduce them to less than 0.004 within 80 degrees. Besides, when the size of package is 25 times larger than the size of chip, the optimized LEE can be obtained. Among of these, the reflectivity of bottom surface also is the major cause of LEE reduction, including reflective mirror layer of flip-chip and white paint layer of the package. If we could increase the reflectance of these layers, the LEE will be enhanced about 10 to 20% and the CSU won’t be influenced. Finally, in order to further improve the CSU, the different concentrations of nanoparticle doped in different position of the package is analyzed.. From the simulation results, for Type I, we can find that when the concentration is up to 5%, the average CSU can be reduced to 0.00064, and all are less than 0.001 within 80 degrees.

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