表面電漿激發元(SPR)共振光譜是一種極具前景的生物傳感技術，具有實時、無生化標記、靈敏和精確檢測等優點。基於在棱鏡和薄膜金屬界面處衰減的全反射產生的漸逝波場從理論上解釋了表面電漿體共振現象。 隨著金屬頂部的折射率發生變化，表面電漿共振的響應也會發生變化。可以通過觀察反射光譜來識別類型和濃度。 用於傳感器的電漿體材料主要是貴金屬，例如金或銀，其物理現象可藉由Drude的模型基於金屬表面局部電子的振盪提供解釋。由於其穩定性和敏感性，金是SPR最理想的材料，儘管其敏感性理論上不如銀高。金和玻璃基板之間的粘合金屬的常規選擇是鉻，但另一種選擇可以是鋁，因為它在可見光中的折射率較低。在這項研究中，我們製作並分析了鋁-金表面電漿共振傳感器的表面電漿共振性能，並與鉻金系統進行了比較。 實驗結果表明，鋁金表面電漿體共振傳感器對去離子水中乙醇濃度的微小變化更敏感。 這種鋁金表面電漿體共振傳感器的設計和製造對於提高當前鉻金表面電漿體共振傳感器的性能非常重要。 ;Surface plasmons resonance (SPR) spectroscopy is a highly promising technology in biosensing that provides many advantages with its real-time, label-free, sensitive, and precise detection. SPR phenomena were theoretically explained based on the attenuated total reflection (ATR) generated evanescent field at the prism and thin film metal interface. As the refractive index on the top of the metal changes, the response of the SPR will also change. The type and concentration can be identified by observing the spectrum of reflection. Plasmonic materials used for sensors are mainly noble metals such as gold or silver, physically explained by Drude’s model based upon the oscillatory of localized electrons on the metal surface. Due to its stability and susceptibility, gold is the most ideal material for SPR, although its sensitivity is theoretically not as high as silver. A conventional choice for the adhesive metal between the gold and the glass substrate is chromium, but an alternative selection can be aluminum for its lower refractive index in visible light. In this study, we fabricated and analyze the SPR performance of Al-Au SPR sensors and made comparisons to the Cr-Au system. Experimental results indicate that the Al-Au SPR sensors are more sensitive to the minute changes in chemical concentrations of ethanol in DI water. The proposed design and fabrication of this Al-Au SPR sensor are very essential to improve the performance of current Cr-Au SPR sensors.
