CMOS MEMS製程是直接從一般IC製造中的CMOS製程加上微加工技術，使其具有機械功能，所以使用CMOS MEMS製程來製作微機電系統元件，不僅具有一般微機電加工技術的優點，也因為與一般IC製程完全相容的特性，十分容易與現有的IC電路整合，形成一個完整的微機電系統。

本研究提出一個可同時致動與感測之元件設計與製作，透過標準CMOS製程，輔以兩道後製程蝕刻，完成元件之製作。元件由一個中心平板與四根懸吊的支撐臂所組成，支撐臂在中心平板的對角線上分別定義一對熱致動臂及感測臂之設計，熱致動臂將帶動中心平板產生出平面位移，平板的位移將連同牽引壓阻感測臂產生形變，可得到感測之回授訊號。本研究提供一個完整之設計流程，包含了元件之設計模擬、CMOS後段製程與量測結果等，並對未來在類似之延伸應用，提供完善參考依據。

Nowadays, mature CMOS standard process is not restricted itself in IC fabrication but steadily integrates MEMS on a monolithic single chip called CMOS MEMS. IC and MEMS fabricated under CMOS process could eliminate processing steps and their complexity. The merit of monolithic integration reveals SoC achievability. Most developing or production MEMS devices fabricated under CMOS process are integrating sensors and ICs. Nevertheless, integration of micro transducers including actuator, sensor and IC will make system multi-function and precision controllability.

This study demonstrates an integration of actuating and sensing mechanism which consisted of one plate structure, two thermal actuators, and two piezoresistive sensors. Thus, the mechanism of the plate is sensed and controlled by the sensors and actuators, respectively. This micromachined mechanism was realized using a standard UMC 0.5 µm 2 poly and 2 metal CMOS process. After conventional CMOS process, post CMOS process is necessary to release MEMS device, which adopts RIE treatment and TMAH wet etching. By external measurement, we have characterized the device’s performances by static operation, dynamic performance, and actuating temperature distribution under steady state. This study proposes a complete design flow for similar CMOS MEMS applications including simulation, post CMOS process, and measured results.

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