表面增強拉曼光譜（Surface-Enhanced Raman Spectroscopy, SERS）是一種強大的分析技術，可以將分子的拉曼散射信號增強數個數量級。近年來，人們對將SERS應用於生物學、醫學和環境科學等領域越來越感興趣。然而，開發具有高靈敏度和可重複性的SERS基板仍然是一個挑戰。
在本研究中，我們展示了透過有機金屬化學氣象沉積法(Metal-Organic Chemical Vapor Deposition, MOCVD)在藍寶石基板上成長的氮化銦鎵(InGaN)量子井於SERS上的應用。我們製備了不同銦含量的氮化銦鎵量子井、也在量子井表面覆蓋不同厚度的GaN保護層。這些樣本的目的，是要利用InGaN量子井的高電子濃度、及可調節的能帶，增強DNA的SERS訊號。
我們發現，3層QW發光波長為488nm，銦含量約為15.4%的氮化銦鎵量子井可產生最強的DNA SERS訊號。此外，我們還觀察到不同厚度的表面保護層對SERS強度的影響，並發現較薄的保護層，可以提高SERS強度。這些結果為進一步開發高靈敏度和可重複性的SERS基板提供了有用的參考和指導，同時也拓展了氮化銦鎵材料在生物、醫學和環境科學等領域中的應用前景。

In this study, we demonstrate the application of indium Gallium Nitride (InGaN) Quantum Wells (QWs) grown on sapphire substrates using Metal-Organic Chemical Vapor Deposition (MOCVD) for Surface-Enhanced Raman Spectroscopy (SERS). We prepared InGaN quantum wells with different indium compositions and surface-cap-layer thicknesses. Varying the band structure with the MOCVD conditions, we were able to control the electron concentration confined within the QWs, and maximize the SERS intensity of DNA dropcasted on the QW surface.
It is found that the three-repeat QW with the indium composition of 15.4 % (emission wavelength: 488 nm) exhibited the highest SERS intensity for DNA detection. Furthermore, we observed the influence of different thicknesses of cap layers on the SERS performance and found that thinner cap layers enhanced the SERS intensity. These findings provide valuable insights and guidance for the development of highly sensitive and reproducible SERS substrates. Additionally, they expand the potential applications of InGaN materials in the fields of biology, medicine, and environmental sciences.

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