本研究利用接觸式金屬轉印 (Contact transfer and metal mask embedded lithography, CMEL) 技術定義次微米的陣列圖形，結合舉離及熱退火製程可製作陣列式金屬微奈米粒子。本研究的製程可使用不同母模仁改變金屬粒子陣列的大小與形狀；或經由改變所蒸鍍金屬層的厚度，在一定範圍內控制金屬粒子的大小；亦可透過混合疊層各種不同的金屬層，以製作合金粒子。以上特點均可應用於陣列金屬粒子的局域性表面電漿共振效應 (Localized Surface Plasmon Resonance Effect, LSPR Effect) 的研究與元件製作。本研究製程可在1 cm x 1 cm的範圍佈滿六角最密堆積，週期400 nm，直徑90 nm的銀粒子。
本研究在實驗上觀察出具金 (Au) 或銀 (Ag) 金屬陣列結構的ITO玻璃基板，其穿透光譜在波長約550 nm時會出現一窄頻穿透谷值。使用Lorentz-Drude model 搭配有限差分時域法 (Finite difference time domain method, FDTD) 軟體模擬實驗現象，發現其窄頻穿透谷值來自於陣列式週期排列之金屬結構與ITO層的電場偶合，近一步增強金屬結構的局部電場，最後激發出ITO層的電漿共振。此一陣列式週期排列金屬結構與ITO層的電漿現象可望應用於多種不同的光電元件。

In this study, contact transfer and metal mask embedded lithography (CMEL) is applied to define and pattern arrayed metallic structures which have feature sizes in the sub-micrometer or nanometer scales. Combining with lift-off and thermal annealing processes, it is possible to fabricate arrayed matellic micro/nano particles on a variety of substrates, including ITO glasses. The dimensions, shapes, and arrangements of these arrayed metallic mciro/nano-structures can be easily adjusted by using different type of imprinting molds. The size and material combination of the obtained metal particles can be controlled by the thicknesses and varieties of metallic films deposited during the lift-off process. Such a flexibility in the fabrication of arrayed metallic micro/nano-structures plays an critical role in the investigation of localized surface plasmon resonance effect (LSPR Effect) and related devices. This study currently can make hexagonal array with a period of 400 nm and metallic nano-particles with a diameter of 90 nm diameter covering an area of 1 cm x 1 cm in size.
In this study, it is observed in experiments that gold or silver metallic array structures deployed on the surface of an ITO substrate will demonstrate a narrowband low transmittance spectrum near the wavelength of about 550 nm. Using the Lorentz-Drude model and a FDTD simulation software, it is found that the narrowband low transmittance spectrum is associated with electromagnetic field coupling between the metal micro/nano-structures and the ITO thin layer. This electromagnetic field coupling induces significant plasmon resonance in the ITO layer underneath the arrayed metallic micro/nanao-structures. Based on this observed phenomenon and its theoretical analysis, new optoelectronic devices can be designed and developed in the future.

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