在這項研究中，我們通過結合沉積銀奈米顆粒進行金屬催化蝕刻和氫氧化鉀鹼性溶液蝕刻的方法，成功地在(001)矽單晶基材上製備大面積準直排列的尖錐狀矽單晶奈米線陣列，並藉由調節蝕刻條件控制尖錐狀矽單晶奈米線的長度與形貌，此外本實驗亦結合無電鍍金屬催化蝕刻法將矽基材薄化，使之具有可撓曲的性質，更在其上製備尖錐狀矽單晶奈米線陣列。接著為了製備各式鎳/蕭基接面結構之光感測元件，本實驗分別蒸鍍鎳金屬和鋁金屬在試片的正面與背面，並進行一系列的量測。 由 SEM 和TEM 可檢測尖錐狀矽單晶奈米線具有相當良好的長寬比和異向性。在可見光-近紅外光譜測量中，所製備之尖錐狀矽單晶奈米線陣列從可見光範圍到紅外光範圍皆表現出優異的抗反射能力，其抗反射性能的增強可歸因於尖錐狀矽單晶奈米線對光捕捉和漸變折射率。在近红外光偵測系統研究中，所製備之各式鎳/矽蕭基接面結構光感测元件皆在無任何外加偏壓下進行量測，並以940 m近红外光燈源進行照光。實驗的結果表示，本研究所製備的鎳/尖錐狀矽單晶奈米線蕭基接面結構具有相當優異的靈敏度與響應時間，且將其製備成超薄可撓曲元件時仍保有幾乎相同的響應時間。 ;In this study, we present the successful fabrication of vertically-aligned, tapered Si nanowire arrays on (001)Si substrates by using a method combining Ag-nanoparticle catalytic etching and KOH etching process. The length and morphology of the tapered Si nanowires can be readily controlled by adjusting the etching conditions. Furthermore, we combined the electroless metal-catalytic etching to make the substrate thinning and have flexible properties. UV-Vis-IR spectroscopic measurements showed that the produced tapered Si nanowires exhibited excellent broadband antireflection properties from the UV to near-infrared (NIR) wavelength range. The optoelectronic study showed that the produced tapered Si nanowire-based NIR photodetector was able to operate at zero external voltage bias and exhibited high sensitivity to 940 nm NIR light and a fast response speed. The obtained results suggest that the facile approach proposed here promises to be applicable for fabricating various high performance Si-based NIR/IR photodetectors.
