利用金屬奈米粒子增強石墨烯光感測器效能

Enhanced Efficiency of Graphene Photodetector via Metal Nanoparticles

劉翔昇(Xiang-sheng Liu)

指導教授 ： 涂維珍

中原大學/電機資訊學院/電子工程研究所/碩士(2016年)

https://doi.org/10.6840/cycu201600802

摘要

近年來，因為二維結構的石墨烯具有獨特的光學和電學特性，使它成為可運用於各種裝置上的有利材料，如感測器和光伏元件等。不幸的是，石墨烯元件的性能可能因其單原子層厚度特性而受到限制。為了克服這個阻礙，研究員提出把石墨烯搭配表面電漿效應或將其合併於特殊腔體結構以改善元件性能。但是，利用表面電漿共振效應或光子腔體的方式來增強石墨烯特性往往需要使用昂貴的電子束微影系統或是經過繁瑣的光蝕刻步驟，這樣一來，限制了低成本與大量製程的可能性。在本篇論文裡，我們使用簡單且容易製作的電漿結構，我們將單層石墨烯/矽基板上的石墨烯結構部分搭配了銀奈米粒子，藉由實驗量測的數據和有限差分時域法（FDTD）模擬的結果，我們發現藉由控制奈米粒子分佈密度與奈米顆粒的大小，能夠顯著的提高可見光區的光吸收，這將會對未來設備的應用產生很大的幫助。

關鍵字

石墨烯 ； 表面電漿共振 ； 光感測器

並列摘要

Recently, two-dimensional graphene with unique optical and electrical properties makes it a promising candidate for various devices, such as sensors and photovoltaics. Unfortunately, the performance of the single-layer graphene device may be limited due by its one-atomic-layer thickness. To order to overcome the obstacle, corporation of graphene with plasmonic structure or integrating graphene with cavities have been proposed to improve the device performance. However,those such enhancements achieved by the surface plasmon resonance effect or photonic cavities commindlly done by using the expensive e-beam deposition or complex photolithography that inhibit the low-cost and high-throughput production. Here, we report a simple and easy-fabrication plasmonic structure built by the graphene incorporated with silver and gold nanoparticles on the single-layer graphene/Si substrate.In terms of the measured and finite-difference-time-domain (FDTD) simulated results, the optical absorption of graphene with controlled density and the size of nanoparticles can be significantly enhanced in the visible region ,which can be beneficial for a variety of future device applications.

並列關鍵字

Graphene ； Surface plasma enhanced ； photodector

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