本論文是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（LTPS）上研製蕭特基MIS二極體式一氧化碳感測器。吾人選擇TiO2, ZnO, 以及SnO2三種材料作為元件的絕緣層。從實驗結果得知，以SnO2對一氧化碳氣體的感測能力最佳。該元件在200℃，逆偏壓3V及3000ppm的CO + air的環境下，其最佳的靈敏度為1560%，並且對於較小濃度(50ppm)的一氧化碳濃度也具有足夠的感測能力。
此外，吾人也研究不同厚度SnO2對於元件感測特性的影響，發現在薄膜厚度為20nm時最好。並針對不同的摻雜類型 LTPS 上所做之元件分析，發現磷摻雜元件之感測性質較佳。另外，吾人探討元件操作溫度對於一氧化碳感測特性的影響。觀察從27℃、100℃,200℃到300℃元件對於一氧化碳氣體的偵測能力，發現溫度越高，感測特性也隨著提升。但到300℃時因MIS元件特性已被破壞，致使元件不再具有感測能力。

In this thesis, we used the excimer laser annealing (ELA) prepared low temperature poly-silicon thin film (LTPS) on glass substrate to fabricate the Schottky diode-type (metal/insulator/semiconductor) carbon monoxide sensors. Three oxides (TiO2, ZnO, and SnO2) were chosen to as the insulator layer. The experimental results show the Schottky diode (Au/ SnO2/c-Si ) has the highest sensitivity (1560%) under 200℃, 3V reverse bias, and 3000ppm CO + air ambient. The sensitivity is higher than that of reported 5.6% of bulk ZnO Schottky diode, and 50% of MO3/TiO2 resistance type under 500ppm CO + ambient. In addition, under the same condition, the sensor showed also an enough sensing ability to 50ppm carbon monoxide.
Furthermore, the effect of various SnO2 thicknesses on the CO sensing ability was investigated, and found the device with 20nm thick SnO2 has the highest sensitivity. Besides, we also improved the property of the LTPS with Phosphorous doping, or Boron doping, and found that the device with the Phosphorous doped LTPS has a better sensing performance. Moreover, a higher operating temperature is better to sense the CO gas, but the sensing function will be lost under 300℃ ,due to the fail of the MIS junction characteristic of the diode.

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