呼吸訊號是人體重要的生理訊號之一，尤其對於嬰幼兒與老年人。因此本論文實現一個整合感測器與電路的呼吸感測微機電系統，在晶片中實現微尺寸的懸臂樑結構與前端放大和濾波之電路。感測器會因所受的外力及溫度的變化，而產生電阻值的改變，而本系統以兩種方式來將電阻值轉換成電訊號，分別為電流式與電壓式，並設計對應之放大電路，此外，系統中亦包含低頻的低通濾波器，其截止頻率為2.6Hz。
本論文呈現詳細感測器、電路與系統的模擬與量測結果，包含感測器對壓力與溫度變化而產生形變與電阻值變化的模擬，及實際感測器的結構和及溫度的影響、系統對呼吸、流速與溫度的量測結果。比較模擬與量測的結果，則可推導與修正感測器的模型。晶片大小為1.32x2.28mm2，電壓式系統消耗2.87mW，電流式系統消耗10.23mW，另外，此晶片是採用0.35μm2P4M製程以及加上MEMS後製程製作。

Respiration is one of the most important physiological signals of human, especially when taking care of babies and elders. A respiration detection system integrating both sensors and circuits into a single chip has been implemented. This system includes the micro-sized cantilever structure and the sensing circuits that can amplify and filter the sensed signal. When the pressure applied on the cantilever or the temperature changes, the resistance of the sensor changes. Two types of circuits are designed in this work to convert the variation of resistance to either voltage or current signal, which then is amplified. Moreover, a low-pass filter with its cutoff frequency locating at 2.6Hz was designed and implemented into the chip.
Both simulation and measurement results of sensors, sensing circuits, and the overall system are presented in the thesis, including the simulation and measurement of the sensors’ characteristics with respect to the applied pressure and temperature, and the data by measuring respiration, flow speed and different temperatures. By analyzing these data, the accuracy of sensor modeling can be greatly improved, which plays an important role for future design. The voltage-mode system dissipates 2.87 mW and the current-mode system dissipates 10.23 mW. Besides the chip size is 1.32x2.28 mm2 and is fabricated by using 0.35um 2P4M CMOS process and MEMS post-process.

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