本研究期望設計一個應用於光達系統的電磁式驅動微機電掃描鏡，相較於其
他應用，此研究希望製作出擁有較大鏡面尺寸及轉動角度的掃描鏡，為了感測結構轉動時的角度，所以利用多晶矽及N-well製作壓阻轉角感測器，透過掃描鏡轉動帶動壓阻產生形變，使壓阻阻值變化，進而產生電壓訊號以進行轉角感測。
本研究使用TSMC 2P4M 0.35 μm製程，將電磁式驅動掃描鏡結構及轉角感測電路整合於單一晶片上，晶片面積12 mm × 10 mm，另外針對後製程進行優化，以精準、低成本的方式開發一套完整的後製程流程，經量測後得到快軸同相位擺動模態的共振頻率為1205 Hz、慢軸扭轉模態的共振頻率為418 Hz，藉由掃描鏡反射在屏幕上的雷射掃描軌跡量測光學轉角，在快軸同相位擺動模態下，驅動電流為24.85 mApp時，快軸光學轉角可達37.65°、在慢軸扭轉模態下，驅動電流為3.728 mApp時，慢軸光學轉角約為19.06°，規格符合地面機器人的光達系統應用。感測電路部分則完成以壓阻感測器感測結構轉動角度並驗證以N-well作為壓阻材料的感測器其感測度較多晶矽壓阻感測器的感測度高。

關鍵字：微機電光達、電磁式、掃描鏡、壓阻感測。

An electromagnetically driven scanning mirror is studied in this thesis for application in a LiDAR system. The scanning mirror is desired to have a larger mirror plate size and a larger rotation angle than those for other applications. In order to sense the rotation angle, piezoresistive sensors made of polysilicon and N-well are deposited on the structure. The piezoresistives change associated with the rotation angle is converted to a voltage signal by on-chip circuits.
In this study, the TSMC 2P4M 0.35 μm process was used to integrate the electromagnetically driven scanning mirror and the sensing circuit on a chip, with a chip area of 12 mm × 10 mm. In addition, for post-process optimization, a precise and low-cost method is used to develop a complete set of post-production process. The measured fast- and slow-axis resonant frequencies are 1205 Hz and 418 Hz, respectively. The optical rotation angle is measured by the laser trajectory reflected by the mirror plate on the screen. The fast- and slow-axis optical angle are 37.65° and 19.06° at the driving currents of 24.85 mApp, and 3.728 mApp, respectively. The design meets the LiDAR specifications for the ground robotics application. As for the sensing performance, the sensitivity of N-well piezoresistor is higher than that of polysilicon piezoresistor.

Keywords: MEMS LiDAR, Electromagnetic, Scanning Mirror, Piezoresistive Sensing.

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