本研究以標準CMOS製程製作了一個紅外線焦平面熱感測陣列，並以PMOS電晶體作為感熱元件，其感測原理為將吸收紅外線熱輻射所產生之溫度差轉換為MOS電晶體的電流變化。有別於其他熱感測較為常見的感測原理，本研究期望透過MOS電晶體作為主動元件的特性，做出一個高響應度的感測陣列，以此驗證MOS電晶體作為感熱元件的高度發展性。
本研究使用 TSMC 2P4M 0.35 μm 製程，製作了8 × 8紅外線感測器陣列，透過讀取電路的設計將PMOS電晶體電流對溫度的變化轉換為電壓。另外設計了兩種不同的電晶體偏壓點，藉此比較電晶體在不同的操作區域下對於紅外線熱感測的效能優劣。在結構方面設計了一套後製程流程以增進感熱元件的溫度變化，其中利用金屬濕蝕刻定義了感熱元件結構形狀，並以矽蝕刻使元件底層的矽基質變薄。經量測後得到電晶體的電流溫度係數在飽和區域與次臨界區域分別為1.78%/K以及4.03%/K，感測器的熱時間常數10.6 ms，而響應度與雜訊等效功率(NEP)在飽和區域下則分別為1.72 x 10^7 V/W以及0.44 pW/Hz^1/2。

In this study, an infrared focal plane array was fabricated with a standard CMOS process, and the thermally isolated PMOS transistors were used as sensing elements. As a temperature sensitive element, a MOS transistor is able to convert the temperature difference generated by the absorption of infrared radiation into the current change of itself. Different from other common sensing principles for infrared thermal detection, the characteristic of MOS transistors as active components would be a great advantage for reaching high responsivity. Thus, this research aims to design and fabricate a PMOS transistors IR focal plane array with high performance, and verify the potential of MOS transistors in infrared sensing.
In this study, the TSMC 2P4M 0.35 μm process was used to fabricate an 8 × 8 infrared sensors array. The change of PMOS transistor current caused by infrared radiation is converted into output voltage through a readout circuit. In addition, two bias points are designed, so we can compare the performance in different operating regions of MOSFETs. A post-process is also designed to improve the thermal isolation of sensors. The structure was defined by metals and would be released by wet etching, while silicon etching was performed in order to decrease the thickness of silicon substrate under sensors. The measured temperature coefficient of current (TCC) in saturation region and subthreshold region are 1.78 %/K and 4.03 %/K respectively. The thermal time constant is 10.6 ms, and responsivity and noise equivalent power (NEP) can reach 1.72 x 10^7 V/W and 0.44 pW/Hz^1/2 respectively in saturation region.

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