表面結構及基板圖案對發光二極體光功率之影響

The Influences of Surface Structures and Pattern Substrate on the Light Output Power of Light-Emitting Diode

倪慶懷(Ching-Hwai Ni)

指導教授 ： 李有璋

中原大學/工學院/機械工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000663

摘要

本篇論文主要是利用奈米壓印的精密製造技術，建構表面結構於發光二極體(LED)，藉以破壞全內反射以及降低菲涅爾散失來提升光萃取效率。
奈米壓印技術首先使用乾或濕蝕刻方式製作出不同結構的矽母模仁，並以聚二甲基矽氧烷(PDMS)彈性材料複製出凹凸相反的子模仁，然後運用熱壓成型技術將聚甲基丙烯酸甲酯(PMMA)材料建構於一般LED與圖樣化藍寶石LED的透明導電膜上；並且為了增進壓印結構表面的散射效應，再經由離子轟擊方式，產生奈米級粗糙化的效果，最後以量測系統量測出各式表面型態結構對LED電特性與光特性的影響。經由壓印與粗糙化方式製作的發光二極體，其順向偏壓與原本LED比較，都維持在 ± 0.1 V的誤差範圍，表示相關製程並不破壞原來的電特性；對光特性而言，若是壓印金字塔結構於LED表面，出光效率將提升將近33 %；若再運用奈米表面粗糙化製程，光效率可再提升4~5 %。當以上結構建立於圖樣化藍寶石LED，則透過LED表面結構與基板微結構的兩大效應，出光效率將大幅增加85.9 %。
透過PDMS軟性模具，本論文成功達成兩吋全晶圓壓印技術，因此本壓印製程將可與現行量產製程整合，符合於商業化需求。

關鍵字

發光二極體

並列摘要

The subject of this thesis is to use nanoimprinting technology to fabricate surface structures on the light-emitting diode (LED) to ruin the total internal reflection (TIR) and also reduce the Fresnel loss to enhance the light extraction efficiency.
The dry or wet etching method was performed to fabricate silicon master molds with different structures, and then the replica molds with opposite structures were made of elastomer polydimethylsiloxane (PDMS). The thermal embossing technique was introduced to fabricate polymethylmethacrylate (PMMA) structures on the conventional LED and patterned sapphire substrate (PSS) LED respectively. In order to increase the scattering effect, ion bombardment was used to generate nanoroughness on the imprinting structures. Finally, the samples were measured for the electrical and optical characteristics. The tolerance of forward voltage is ± 0.1 V, that means the electrical characteristic was not damaged after imprinting process and roughened treatment. An approximate 33% improvement in light output power was obtained using the pyramid profile when compared with the planar LED. The roughness effect provided an approximate 5% efficiency enhancement. The total light enhanced efficiency increased to 85.9% by integrating the imprinting pyramid structure, PSS, and surface roughness.
In this study, PDMS was used as a flexible mold material for the 2-inch wafer imprinting process which could be integrated with conventional chip process of commercialized LED.

並列關鍵字

LED

參考文獻

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