臺灣博碩士論文加值系統

發光二極體的特性包含高耐用性，壽命長以及低能源消耗。因為這些特性，發光二極體將可在背光模組以及一般照明取代現有的光源。對於高亮度發光二極體而言，封裝是一個極為重要的因素。封裝最重要的兩個環節即為光學設計與熱管理。我們將會在此論文研究如何提高光學方面的外部效率與均勻度。

在單晶片封裝中，我們使用微透鏡陣列來有效提高光學效率與均勻度，此微透鏡陣列的特性將會利用實驗與模擬結果來了解。藉由考慮到側杯的一次反射，微透鏡陣列的位置將會被小心的設計。在加入此微透鏡陣列後，效率從0.66提升至0.77。而同時，在比較峰對谷值與標準差後也可發現均勻度已經有效改善。

在考慮完單一封裝之後，我們設計一個擁有四個發光二極體的多晶片封裝。每一個晶片與晶片的距離是1毫米。我們藉由研究其中單一綠光發光二極體的均勻度來證明此多晶片封裝系統是可以有效讓紅光、綠光、藍光混光。經由這分析，我們已經得到微透鏡陣列與矽封裝應用在未來的高亮度發光二極體是非常適合的。

Light-emitting Diode (LED) is a suitable light source in general lighting and backlight module due to its robustness, long life, and low power consumption. For high brightness LED, packaging has become a crucial factor. The issue of packaging can be divided into optical design and thermal management. External efficiency and uniformity of optical design will be discussed in this thesis.

To increase external efficiency and uniformity in single chip LED, we introduce microlens array. The characteristic of microlens is discussed through experiment and simulation result. The location of microlens is cautiously designed by considering cup reflection. Efficiency is increased from 0.66 to 0.77 with specific microlens film in single packaging. Meanwhile, the uniformity is also improved with the comparison of peak-to-valley value in ray pattern and standard deviation.

On the other hand, LEDs cluster together in multi-chip packaging. The gap between LEDs is about 1mm. We focus on a green chip LED to demonstrate that RGB lights can be mixed through microlens film. After these analyses, with efficiency and uniformity improvement we prove that the silicon packaging which is compacted microlens film is adequate for future HBLED.

Abstract…………………………………………………………………………………Ⅰ
中文摘要……………………………………………………………………………….Ⅱ
致謝…………………..………………………………………………………………...Ⅲ
Content…………………………………………………………………………………Ⅳ
List of figures…………………………………………………………………………..Ⅵ
List of tables………….………………………………………………………………...Ⅹ
CONTENT
Chapter 1: Introduction…………………………………………………………………..1

Chapter 2 Concerns of LEDs packaging
2.1: Packaging roadmap and silicon packaging…………………………………4
2.2: MEMS technology…………………………………………………………7
2.3: Review of microlens……………………………………………………….9
2.4: RGB mixing………………………………………………………………11
2.5: Monte-carlo method and Tracepro………………………………………..17

Chapter 3 Optical design
3.1: Total internal reflection and Material selection…………………………..19
3.2: Improvement of efficiency and microlens design………………………..21
3.3: Cup design………………………………………………………………..24
3.4: Encapsulant effect and uniformity………………………………………..29


Chapter 4 Experiment and discussion
4.1: Experiment setup and result……………………………………………...32
4.2: Singel packaging
4.2.1 Uniformity improvement in single packaging…………..…………40
4.2.2 Location effect in efficiency aspect……………..…………………42
4.3.3 Summary of single packaging……………………………………..46
4.3: Single wavelength LEDs multi-chip packaging
4.3.1 Full microlens film application…………………………………….46
4.3.2 Specific microlens array film in multi-chip design………………..51
4.4: RGGB LEDs multi-chip packaging………………………………………53

Chapter 5 Conclusion…………………………………………………………………..59

References……………………………………………………………………………...61

Appendix
Tracepro setting of chip pattern……………………………………………….66

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