LED的技術發展突飛猛進，隨之應用也不斷開展，造就產業大躍進，由於應用的不同需求，技術也應運而生。
透明導電層（Transparent Conductivity Layer；TCL)是LED在電傳導與光傳導的一個關鍵設計，為了減低電傳過程的損失，我們使用金屬作為電傳的渠道，然而金屬層會造成光吸收與光屏蔽，所以TCL作為短區域的電傳導層可以兼顧光電傳導的需求，然而因折射率差異造成介面光傳導損失則是另一個挑戰，這項工作的主要焦點之一是研究GaN LED的表面中TCL的混合結構。使用可能的材料和結構的組合來產出不同特性的TCL，其中發現石墨烯是最好的選擇之一。研究中，我們還將現有LED在不改變既有的製造技術和磊晶結構下，輸出功率提高了18％。
一般晶片設計因為切割走道的預留，損失部分的發光面積，通過對未被利用的n-GaN層的走道，進行納米加工來提高輸出功率，證實了增強的光提取是來自於原本沒有光分佈的空間，這項研究提供了現有LED在光功率提升的一種新方法。

This work aims for a high efficiency LED using a novel transparent conductive layer and new approach for texturing. For both the light extraction and current spreading consideration, we have to design not only material base but also the surface condition. One of the primary focuses of this work is to study the hybrid structure of TCO in textured surface of InGaN based LED. Different TCO is examined with possible combinations of textured and structures where graphene was found to be one of the best choices. In this study, we also enhanced the output power of conventional LEDs by 18% without alterations to the existing fabrication techniques and to the multi-quantum well junction. The output power is improved by nanotexturing the street of the n-GaN layer that was unexploited, for the enhancement of the optical or electrical properties. We observed similar light output patterns and I-V characteristics for LEDs with and without street nanotexturing, confirming that the enhanced light extraction has been achieved without a change in the spatial distribution of light. This study provides a new approach for the output power enhancement of all types of existing LEDs.

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