本研究中，我們以氮化銦鎵（InGaN）奈米量子井作為基板，並覆蓋鋁（Al）奈米結構之表面增強拉曼散射（Surface-Enhanced Raman Scattering, SERS）晶片，以提升對 β-carotene 乙醇溶液之偵測靈敏度。研究中採用電子束蒸鍍技術（E-gun）於 InGaN 基板上沉積不同厚度（30、35、40 nm）的鋁膜，並以快速熱退火（Rapid Thermal Annealing, RTA）於不同溫度（275°C、300°C、325°C、350°C）進行處理，以調控鋁奈米顆粒的形成與分佈。製程完成後，在各樣品表面滴加濃度為 100 µM 的 β-carotene 乙醇溶液5滴，並以波長 532 nm 的雷射拉曼光譜儀進行量測。

透過實驗觀察，不同鋁厚度與退火溫度對鋁奈米結構之尺寸、密度與均勻性具有顯著影響，進而導致 SERS 增強效應表現出不同的拉曼訊號強度。本研究結果顯示，適當控制鋁膜厚度與退火條件可優化表面奈米結構，有效提升 β-carotene 分子的拉曼訊號強度。此一研究提供未來在優化以鋁（Al）奈米結構之表面增強拉曼散射晶片的製程條件。

In this study, a Surface-Enhanced Raman Scattering (SERS) chip was developed using indium gallium nitride (InGaN) quantum wells as the substrate and aluminum (Al) nanostructures as the plasmonic layer to enhance the detection sensitivity of β-carotene in ethanol solution. Aluminum films with varying thicknesses (30, 35, and 40 nm) were deposited on InGaN substrates via electron beam evaporation (E-gun), followed by rapid thermal annealing (RTA) at different temperatures (275°C, 300°C, 325°C, and 350°C) to control the formation and distribution of Al nanoparticles.
After the fabrication process, five drops of 100 µM β-carotene ethanol solution were applied to each substrate, and the Raman spectra were measured using a laser Raman spectrometer with an excitation wavelength of 532 nm. Experimental observations revealed that both the Al film thickness and annealing temperature significantly influenced the size, density, and uniformity of the Al nanostructures, resulting in varied SERS signal intensities.
The results indicate that optimizing the thickness of the Al layer and annealing conditions can effectively improve the nanostructure morphology and enhance the Raman signal of β-carotene. This study provides valuable insight into the fabrication process of Al-based SERS chips and offers a reference for future optimization of such platforms.

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