本論文係探討利用準分子雷射退火(Excimer Laser Annealing, ELA)技術在玻璃基板成長的低溫多晶矽薄膜上研製低成本高性能MIS蕭特基二極體式氫氣感測器。由實驗結果，我們發現金-半接面結構會受到矽化物與界面態位的控制，使得蕭特基能障高度較不受極化氫原子的影響，因而導致氫氣感測能力差，故須添加絕緣層來改善。而在金屬-絕緣層-半導體接面結構中，則以TiO2作為絕緣層材料的感測元件特性最佳。該元件在逆偏壓1V與氫氣濃度100ppm的操作環境下，呈現2500%的靈敏度及36秒的反應時間(response time)，並顯示很好的再現性與選擇性。
此外吾人並研究利用磷摻雜、硼摻雜及氮電漿處理來改善薄特性，其中以磷摻雜表現的特性最佳。另外在薄膜表面不同粗糙度對元件特性的影響研究中發現粗糙的薄膜表面會有較佳的感測特性。
最後，在27°C、70°C與110°C的溫度變化試驗中，發現較高的操作溫度有助於感測元件的反應速度，但同時會降低靈敏度。

In this thesis, we used the excimer laser annealing(ELA) prepare low temperature poly-silicon thin film on glass substrate to fabricate the MIS Schottky diode-type low cost and high sensitivity hydrogen sensors. The experimental results show the Pd/TiO2/Si MIS Schottky diode has the highest sensitivity (2500%), fast response time τr (36sec), good reliability, and selectivity under 1V reverse bias and 100ppm hydrogen.
Besides, we improved the property of poly-silicon thin film with Phosphorous doping, Boron doping, and nitrogen plasma treatment, and find the Phosphorous doping gains the best improvement. Moreover, a rough surface in poly-Si thin film can enhances the sensitivity.
Furthermore, we find the sensor operated in a high temperature got fast time response, but lowers sensitivity at the same time.

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