金奈米粒子受電場影響時，會造成電子雲的集體震盪而產生表面電漿子，而緊密排列的金奈米粒子對可引發高度局域性的電場共振效應。因此，金奈米粒子被廣泛應用在生醫檢測、表面增強拉曼光譜等領域上。
　　在本研究中，將探討以鐵電微影技術(Ferroelectric Lithography)操縱金奈米粒子在多鐵性材料鐵酸鉍(BiFeO3)上的排列與吸附密度的方法。
藉由控制掃描式電子束顯微鏡(Scanning Electron Microscope，SEM)的電子束加速電壓與電子束照射劑量來改變二次電子散射機率，使BiFeO3局部表面累積電荷，並以表面電位顯微鏡(KFM)的鐵電微影技術(Ferroelectric Lithography)，確認該區域之表面電位。最後將樣品置入金奈米粒子溶液中，使正電位之區塊能吸附表面帶有負電之金奈米粒子；反之負電位則會排斥。
　　以此實驗方法，可使BiFeO3局部表面吸引或排斥金奈米粒子，並調控其吸附密度與區塊大小。

Surface plasmons are coherent electron oscillations that exist at the interface between any two materials, and the excitation of surface plasmons is frequently used in an experimental technique known as surface plasmon resonance (SPR). The most commonly material that people used to excite surface plasmons are silver and gold nano particle.
This study focus on manipulating the arrangement of gold nano particles (AuNPs) on the surface of BiFeO3 (BFO), multiferroic materials, by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).
According to the previous studies, controlling the acceleration voltage and the dose of the electron beam could change the scattering probability of secondary electrons of SEM. By using this technique, the charges could be trapped on the surface of BFO. The positively or negatively trapped charges could be distinguished from surface potential measured by Kelvin probe force microscopy (KFM). The negatively-charged AuNPs would be attracted to the area trapping positive charge. In addition, we could manipulate the arrangement of gold nano particles, due to charges distribution could be modified by AFM in the areas which have scanned by SEM. The different AuNPs patterns would excite different surface plasmon modes.

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