我們用互補式金氧半微機電（CMOS MEMS）製程來設計一個整合式的壓力感測器，預期會用在心血管手術中的血壓量測上。由於需要很小尺寸的元件，所以預期上感測度不會太高。我們使用一個電容式感測電路把壓力引起的電容值變化轉換成震盪器的頻率變化。完成互補式金氧半製程後，接著的後製程會把生醫相容的高分子聚合物沉積在薄膜的上方，而利用犧牲層金屬蝕刻可以釋放在高分子聚合物下的微機械結構薄膜，在某些設計上震盪器感測電路可以直接放在結構薄膜的下面，如此一來又可以節省面積。我們目前的設計量測出來可達到421 kHz/fF的感測度。

We propose the use of CMOS-MEMS technology to fabricate a monolithically integrated pressure sensor intended for blood pressure monitoring during balloon angioplasty. Due to the small device size, a low sensitivity is expected. We employ a capacitive sensing circuit to convert the pressure-induced capacitive change to a shift of the oscillation frequency. The post-fabrication steps after completion of the CMOS include the use of a bio-compatible Parylene coating on top of the membrane, and a sacrificial metal etch to release the micromechanical membrane underneath the Parylene. In some design the readout circuit is a CMOS oscillator which can be placed directly underneath the membrane to save chip area. Our current design shows a sensitivity of 421 kHz/fF.

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