Study of Micro-lens Array Integrated Flip-chip 64*64 GaN Micro-Light-Emitting Diodes Array

微透鏡陣列與 64*64 微型發光二極體陣列之研製

陳伯毓(Chen, Po Yu)

指導教授 ： 吳孟奇 ； 何充隆

國立清華大學/電機資訊學院/電子工程研究所/碩士(2015年)

摘要

本研究以開發圖像顯示用單石化(Monolithic)微型發光二極體(LED)陣列，希望呈現出64 × 64之行列選址式(Row-Column-Addressed)微型LED陣列。並希望未來能結合IC發展成主動式的微型LED陣列，可應用在微影像顯示、無光罩微影(Maskless Photolithography)、光驅基因工程(Optogenetics)等領域。
我們研究開發380nm(紫外光)和450nm(藍光)微型LED陣列，而隨著畫素微縮，載子復合產生之輻射越易離開晶體，因此可以預期輻射場將朝等向性趨近，亦即廣角化。然此廣角化對圖像顯示用之 LED 陣列勢必造成光互擾(Optical Crosstalk)影響圖像品質。而我們64 × 64微型LED陣列的理想封裝架構為採用覆晶技術，亦即顯示圖案將由晶背，即自 Sapphire 面輸出。Sapphire (折射率 ~ 1.8)相對空氣具有較高之折射率,光束折射不似自GaN(n ~ 2.4)進入空氣般有嚴重偏折，但單一畫素所發出之光束，於 Sapphire 內仍漸行漸散，且隨晶背厚度增加，發散影響鄰近畫素程度愈嚴重因此可以預期隨著畫素數量與密度的提高，基板厚度勢必越來越薄，甚至完全移除 (例如採用Laser Lift-Off，LLO 技術)。除盡量提升減薄規格外(基本厚度上限為 100 μm), 亦開發微透鏡陣列技術抑制畫素光束之發散。

關鍵字

微型發光二極體陣列 ； 氮化鎵 ； 微透鏡陣列

並列摘要

In this study, we will develop monolithic micro-light-emitting diodes array (mLEDA) for pattern display, and perform a 64 x 64 row-column-addressed micro-light-emitting diodes array, which have advanced applications in micro-projector, mask-less photolithography, and optogenetics.
We will develop 380 nm and 450 nm mLEDAs in this study. By using the flip-chip bonding technology, the light is come out from the back side of wafer, which is sapphire face, but the light will deflect between the interface of GaN (n~2.4) and sapphire (n~1.8) because of different refractive index, and the light will diverge passing through the sapphire. The large sapphire thickness leads to optical cross-talk, so the light will interfere the adjacent pixels. Thus, the higher density of pixels, the thinner sapphire thickness we need, or we can remove the sapphire by Laser Lift-Off. We also develop micro-lens array technology to focus the light and restrict the divergence of light in our design.

並列關鍵字

Micro-light-emitting diodes array ； GaN ； Micro-lens array

參考文獻

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