本論文使用電磁式微掃描鏡利用羅倫茲力為驅動方式並以雷射作為投影光源，為了能夠感測微掃描鏡的振動行為，運用沉積多晶矽在各扭轉軸上組成壓阻感測器，以利在回授電路做振動控制。
本晶片使用TSMC 2P4M 0.35 um CMOS製程，將電磁式微掃描鏡結構、感測電路與控制電路整合於單一個晶片上，晶片總面積為3.5 mm × 3.6 mm，利用CMOS製程與矽基材來當作結構之質量塊，將快軸與慢軸設計為不同厚度，其中較薄的慢軸可以大幅縮短慢軸長度，降低結構所占面積範圍，另外針對慢軸設計成三根彈簧，可降低應力，避免較大電流驅動時損壞晶片，最後以簡單、低成本的方式開發一套完整的後製程。
完成製程後，微掃描鏡結構之量測結果，快軸共振頻測得為36.6 kHz與慢軸共振頻4.3 kHz，得到與模擬結果一致的模態特性，並且達到SXGA解析度(1280×1024)所需之共振頻。驅動部分採電磁式致動，外部輸入電流至晶片上之線圈與外部磁場交互作用產生勞倫茲力，此方式採用外部磁場與晶片夾45度之架構，驅動雙軸可只需要一組磁場。感測電路部分使用慢軸壓阻感測器，並將輸出的差動訊號經過減法器後，轉為單端訊號，再經過補償電路，確認開迴路增益與相位，符合巴克豪森準則。最後成功的在快軸共振頻達到穩定振盪，投影出一維水平投影，量測其光學角度為3.4度並且此時之驅動電流為6.1 mArms。

An electromagnetic scanning micromirror driven by Lorentz force is studied in this thesis for application in a laser beam scanning projector. In order to produce repetitive scanning at the resonance, polycrystalline silicon deposited on the torsion axis is used to provide piezoresistive sensing of the motion.
The integrated chip containing the mechanical structure, sensing and compensation circuit, is implemented by using the TSMC 2P4M 0.35μm CMOS process. The chip area is 3.5 × 3.6 mm2. By designing torsional beams with different thicknesses for fast and slow scans, the length of the latter can be reduced to minimize the overall scanning mirror size. In addition, the design for the slow axis of three springs can reduce stress and avoid damage to the chip when the larger current driving. We develop a convenient and low-cost post fabrication process and successfully fabricate the scanning micromirror device.
The fabricated micromirror structure designed for SXGA resolution (1280×1024) shows the measured resonant frequencies at 36.6 and 4.3 kHz, respectively, for fast and slow-axis scans. The results are close to the simulated values. Electromagnetic actuation is used for the driving. The Lorentz’s force driving the scanner is created by an external magnet and a current carrying coil. The magnet is placed at 45 degrees relative to the both scan axes. The piezoresistive sensing circuit contains a Wheatstone bridge and a differential-to-single-ended circuit. Through proper gain and phase compensation, sustained oscillation with respect to the fast scan axis is successfully achieved. The optical angle was measured to be 3.4 degrees at 6.1 mArms.

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