ㄧ維奈米結構有許多種，而其製作方式與應用方面亦有所不同，例如於太陽能電池上將使用其相當高的抗反射特性，用於電子場發射元件主要將強調其奈米結構等級的線端可以使其屏蔽效應明顯改善，而應用於感測器則有相當高的比表面積，而感測器方面則是使用其具有高深寬比之特性。

　　我們使用一維矽奈米結構為主要材料以製作氫氣感測器之應用，本研究中我們使用簡單的蝕刻技術創造出不同的蝕刻形貌，藉由場發射電子顯微鏡可以觀察其表面形貌不同，之後再使用拉曼光譜分析矽基板經過蝕刻之後所產生峰值及半高寬之變化，以及使用傅利葉紅外線光譜儀分析，進一步分析其鍵結的狀態。最後再以氣體感測量測系統進行最後的氫氣之量測，並且以電性加以分析。
　　本論文在製作過程中，成功的利用二次蝕刻技術將奈米線做一種變化，形成草堆狀結構之矽奈米結構，以產生我們所研究的感測器元件之結構。其中由場發射電子顯微鏡中可以觀察出表面有明顯的分層變化，可以分為上層奈米線以及中間層奈米線以及底層未被蝕刻之矽基板，除長度的變化之外亦可看出其密度的改變，使用傅利葉紅外線光譜儀在1173cm-1中的Si-O-Si鍵結中的峰值強度也有明顯的改變，另外從拉曼的變化亦可觀察到矽基板之峰值產生紅移的情況發生，最後以氫氣量測系統可以發現此結構對感測靈敏度有明顯提升之效用。在產生草堆狀結構之後再運用添加白金金屬粒子幫助氫氣分子解離以及增加分子進入其金屬半導體接面之速度，以提升其感測靈敏度以及回復時間；除此之外亦使用簡單的蝕刻技術使銀粒子沉積於基板上，再以濕式蝕刻技術進一步創造高密度以及高靈敏度的孔洞結構，最後此種孔洞結構亦藉由過氫氣感測器可觀察出具有較佳之靈敏度特性。

There are many technologies to fabricate one-dimensional silicon nanostructure.
The silicon nanostructures were used for many applications. For example, the silicon nanostructures have high reflection property in solar cell. In the electron field emission, the silicon nanostructures possess the higher aspect ratio and numerous emission sites. For sensor researching, it has higher surface area to volume ratio that can improve the sensitivity.
We fabricated the one dimension silicon nanostructure for hydrogen sensor. In this research, we synthesized different morphology of silicon nanostructure using wet electroless etching technique. The field emission scanning electron microscopy (FE-SEM) was used to observe the surface morphology of silicon nanostructure. The micro-Raman and Fourier transform infrared (FT-IR) was used to investigate the bonding of silicon nanostructure. Finally, we carried out the electrical analyze of gas sensor system with hydrogen sensing.
In this study, we use the two-step wet electroless etching technique to form the straw-like silicon nanowire. It can be observed that some different layers in SEM photographs. The top layer was straw-like silicon nanowire, and the middle layer was straight aligned silicon nanowire, and the bottom layer was silicon base which is the bulk silicon. The straw-like silicon nanowire was found the the bonding of Si-O-Si about 1173cm-1 in FT-IR spectrum. And it also observed some red shift in Raman spectrum. Because of the higher surface area to volume ratio and Si-O-Si bonding, the performance of this straw-like structure hydrogen sensor was improved. Moreover, this hydrogen gas sensor was also modified with Pt nanoparticles, which can enhance the ratio of hydrogen gas dissolve into the metal-semiconductor interface.
Finally we tried to make the porous structure with high density and high aspect ratio also by wet electroless etching technique. This porous possessed the high surface area which had the superior sensitivity.

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