以電化學蝕刻法製備多孔隙矽薄膜及其氣體感測之應用

Fabrication of Porous Silicon Films by Electrochemical Etching Process and Its Application on Gas sensor

蔡如綺(Ru-Chi Tsai)

指導教授 ： 闕郁倫

國立清華大學/工學院/材料科學工程學系/碩士(2018年)

摘要

本論文著重在於以電化學蝕刻法製備多孔隙薄膜，透過不同的參數控制達到不同形貌的薄膜，並將多孔隙應用在氣體感測之應用。
矽(Si)是地球上含量第二豐富的材料，目前已經大量被研究與應用。因次其低成本及良好的本質特性，已經被廣泛應用在半導體產業。近期，隨著能源議題，矽被致力研究於太陽能產業及電池產業上。多孔結構使得電性極佳的矽基板有半導體的性質，且有較大的表面積，獨特的電學性質及光學性質。此外，更能輕易達到大面積(15cm×15cm)的製程。由於製備過程簡易且整體成本較低，因此是非常好的應用材料。其較大的表面積且特殊的電性可以應用在氣體感測上，例如濕度感測、氫氣感測、有機氣體感測、氰化物感測。本文將金電極度在多孔矽薄膜上，利用不同參數的多孔薄膜，探討如何得到最敏感的一氧化氮氣體感測，而施加紫外線光可以使得氣體感測的反應更明顯。

關鍵字

多孔矽 ； 蝕刻 ； 電化學蝕刻 ； 氣體感測

並列摘要

Silicon, the second most abundant material on earth, has been applied on wide range regimes such as, batteries, semiconductor, and solar cell. Because of its low cost and well-developed technology, silicon can be used in many application. Porous silicon (PSi), due to its intrinsic property or the porous structure, has been presented to be fabricated by electrochemical etching.
For the lithium-ion batteries(LIB), the high theoretical capacity for Si is 3597 mAhg-1. However, the volume expansion during lithiation/delithiation limits its cycling performance. The PSi has been exploited to lithium-ion batteries with excellent capacitance, columbic efficiency, and cycling retention.
Recently, PSi has drawn considerable attention for sensor applications because of Its luminescence properties, large surface area, and compatibility with silicon-based technologies. Chemical functionalization of the large surface areas, which can be generated in PSi, show the potential for developing a variety of gas sensors. For this work, the PSi layer apply on NO sensor, and use the UV light to improve the performance. It can easy tell the different concentration of the NO from 0.25 ppm to 5 ppm, and the limit of detection (LOD) is 0.35 ppb.

並列關鍵字

porous silicon ； etching ； electrochemical etching ； gas seneor

參考文獻

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