本研究利用真空熱蒸鍍沉積系統(Thermal evaporation system)，將鎵金屬蒸鍍於固化後之聚二甲基矽氧烷(Polydimethylsiloxane, PDMS)彈性體上。在選用的製程參數下，鎵金屬粒子會沉浸於PDMS基板表面之下，自行排列成大小均一的球形奈米結構，形成一個可利用機械式拉伸調節局域性表面電漿子共振(LSPR)特徵波峰位置之複合材料。沉積於高分子內部可以使鎵金屬奈米粒子大小及分佈較硬基板上的更為均勻，且奈米粒子能穩定存在，然而鎵金屬會浸沒於PDMS基板的機制、以及在不同製程條件下的鎵金屬自組裝結構變化之成因，尚未有研究證實。本研究透過掃描式(SEM)及穿透式電子顯微鏡(TEM)觀察此奈米結構之表面及截面形貌，並且使用光譜儀量測反射之LSPR訊號，將得到之實驗結果進行整理分析後推測出不同自組裝奈米結構之形成機制。此外也利用時域有限差分法(FDTD)之模擬軟體分析不同奈米結構之光學性質，在反射圖譜上得到與實驗結果相符之趨勢，也透過電場分佈圖了解奈米粒子間之交互作用。;In this study, gallium was evaporated on the cured polydimethylsiloxane (PDMS) using the thermal evaporation system. Under our process parameters, the gallium nanoparticles (Ga-NPs) are immersed under the surface of the PDMS substrate and self-assemble into uniform-sized spherical nanostructures, which can be utilized in localized surface plasmon resonance (LSPR) and tuned the characteristic peak position by stretching. Gallium nanoparticles can be well arranged and size-uniformed by deposited into the polymer, and the nanostructure are able to stabilize in the polymer. However, the mechanism of Ga-NPs embedded in the PDMS substrate and the changes of the self-assembled structure under different process conditions have not been confirmed. Therefore, we observed the surface and cross-sectional morphologies of the nanostructures each by SEM and TEM, and also measured the reflection by the UV-Vis spectrometer, in order to figure out the formation mechanism of the Ga-PDMS nanocomposite. In addition, the finite-difference time-domain (FDTD) simulation was used to analyze the optical properties of different nanostructures. The trend of simulation results was consistent with our experiments, and the interactions between nanoparticles were also understood through the electric-field distribution.
