紅外線感測器可應用於各種遠距溫度量測、熱點偵測以及紅外線熱影像等，特別是受到目前全球疫情的影響，使得體溫量測以及熱影像的需求量大為增加，一年內的年均複合成長率高達百分之二十，顯示紅外線感測器的市場價值。因此本次研究中，使用商用的標準CMOS製程平台(TSMC 0.18 μm 1P6M CMOS platform)來設計熱電型紅外線感測元件，而利用製程平台內的二氧化矽層作為紅外線的吸收材料，於8至14微米的波段中具有較高的吸收率，並依照不同的產品應用需求提出兩種尺寸的感測結構設計，同時也因為摻雜後的多晶矽之熱電偶於感測結構內所佔比例較低的因素，可進行熱電偶鋪設的調整，如鋪設比例以及寬度等，在不改變感測結構設計的前提下進行，且因熱電偶的幾何尺寸會影響元件的電阻值，而電阻值大小會影響感測器主要的雜訊量(熱雜訊)，因此透過熱電偶的調整可提升感測器的檢測比，並且為了解決較小的感測面積電壓輸出不足的問題，也提出了新穎的結構設計，大幅增加結構的熱阻，提升了感測器的輸出。並根據最終的實驗結果得知，透過更改熱電偶鋪設時的寬度，在0.5%的些微響應度損失下，可增加28.7%的檢測比(訊噪比)，而透過新穎的結構設計，則是可同時增加146%的響應度以及檢測比，達成紅外線感測器的性能提升。

Thermal Infrared sensor can be applied to remote temperature measurement, hot spot detection, and thermal imager. Due to the global infectious disease, the IR sensor market is rapidly growing in the demand of body temperature measurement and thermal imager. The 20% CAGR (Compound Annual Growth Rate) shows the market is promising. This study employed the TSMC 0.18 μm 1P6M CMOS platform to implement and enhance the thermoelectric infrared sensor with the benefit of higher absorptance in the range of 8 to 14 μm infrared light. Besides, there are two sensing structure designs presented for different further application. Since the proportion of thermocouple in the sensing structure was relatively low, adjusting the dimension of thermocouple only slightly changed the total thermal conduction with the identical sensing structure. Because the total electrical resistance is dominant by sheet resistance, revising the pattern of thermocouple can enhance the detectivity. Although, shrinking single sensor size can bring to higher spatial resolution for thermal imaging, the sensor output voltage is decreased in line with the sensing area reduction. Thus, this study also attempted to propose a novel structure design for responsivity enhancement. Finally, the results shows that the 28.7% detectivity improvement only sacrificed 0.5% responsivity by thermocouple adjustment, and 146% responsivity and detectivity improved by the novel structure design.

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