| 摘要: | 在本研究中，我們於室溫的條件下以奈米球微影術結合金屬輔助催化蝕刻法成功地於(001)矽晶基材上以低成本、安全快速與一步驟之方式製備出大面積規則準直且有序排列之尖錐狀矽晶奈米線結構陣列，並透過調整蝕刻液中乙醇之含量與蝕刻時間對尖錐狀矽晶奈米線的高度與形貌進行控制，所製備出之尖錐狀矽晶奈米線除表現出超疏水性質外，也表現出優異之電子場發射性質，接著則再藉沉積鈷金屬薄膜與高溫熱退火製備具低功函數之尖錐狀二矽化鈷奈米線結構，期望可再次提升電子場發射之性質；並於同時透過SEM與TEM及對應之電子選區繞射圖譜分析鑑定各比例所製備之尖錐狀矽晶奈米線與尖錐狀二矽化鈷奈米線之表面形貌與單晶結構，其各項結果顯示透過上述方法將提供在製備尖錐狀二矽化鈷奈米線於電子場發射源的製程參考。
另外，因尖錐狀矽晶奈米線結構整體呈上窄下寬的形貌，具有漸變折射率之特點，使其可具有不錯之光捕捉能力，而若將其與金屬矽化物製程結合將可提升矽基材料於近紅外光波段之吸收率，因此本研究也將尖錐狀矽晶奈米線結構結合金屬矽化物製程之方式製備尖錐狀二矽化鈷奈米線結構，並對是否於表面製備奈米結構以及矽化反應前後於可見光至近紅外光波段之反射、穿透與吸收率結果進行分析比較，其結果顯示無論表面有無奈米結構，矽化反應後於近紅外光波段之吸收率將具顯著提升的效果，相信上述將矽基材料結合金屬矽化物製程之方式，對於研發各種先進矽基光電元件及近紅外光波段之感測器將能提供製程優化之理想選擇。
;In this study, we successfully fabricated large-area, well-aligned, and ordered arrays of needle-like silicon nanowire structures on (001) silicon substrates at room temperature using a combination of nanosphere lithography and metal-assisted chemical etching. This low-cost, safe, rapid, and single-step method allowed precise control over the height and morphology of the needle-like silicon nanowires by adjusting the ethanol content in the etching solution and the etching duration. The resulting needle-like silicon nanowires exhibited superhydrophobic properties and excellent field emission characteristics. Subsequently, by depositing a cobalt metal thin film followed by high-temperature thermal annealing, we fabricated needle-like cobalt disilicide nanowire structures with low work function, aiming to further enhance field emission properties. The surface morphology and single-crystal structure of the needle-like silicon and cobalt silicide nanowires prepared under various conditions were characterized using SEM, TEM, and corresponding selected-area electron diffraction patterns. These results demonstrate that the proposed method offers a valuable reference for the fabrication process of needle-like silicide nanowires for field emission sources.
Additionally, due to the needle-like morphology of the silicon nanowire structures, which are narrow at the top and wide at the bottom, they possess a gradient refractive index, enabling effective light-trapping capabilities. When combined with a metal silicide process, the absorption efficiency of silicon-based materials in the near-infrared wavelength range can be significantly enhanced. Therefore, in this study, we also fabricated needle-like cobalt silicide nanowire structures by integrating the needle-like silicon nanowire structures with a metal silicide process. We analyzed and compared the reflectance, transmittance, and absorption properties in the visible to near-infrared wavelength ranges for samples with and without surface nanostructures, as well as before and after the silicidation reaction. The results indicate that, regardless of the presence of surface nanostructures, the absorption efficiency in the near-infrared wavelength range is significantly improved after the silicidation reaction. We believe that this approach of combining silicon-based materials with metal silicide processes provides an ideal strategy for optimizing the fabrication of advanced silicon-based optoelectronic devices and near-infrared sensors. |
