積體電路設計與矽晶片製造在現今半導體產業成熟發展下，可做相當程度地整合，跨領域的研究也因此而更加興起，使得微機電系統能夠結合電路整合於晶片上。具感測度的微掃描鏡晶片就是其中之一，利用電磁式驅動結構運動，藉由在轉軸上沉積多晶矽與N-型井的壓阻當作感測器，將訊號透過電路傳遞，可以感測當微掃描鏡的運動時，轉軸上的壓阻形變所產生的訊號，再配合光學量測轉角進行投影應用。
鏡面在振動時在其表面會產生形變，此值不能大於入射光波長的1/10，否則會造成成像位置不正確，故降低了振頻與增加了厚度，然而當增加厚度時振頻會隨之提升，故需要增加彈簧長度及減少彈簧寬度以有效地降低振頻，換來的結果是晶片面積的提升，而降低振頻也會使掃描鏡的成像規格下降，因此在本論文先經由Ansys有限元素分析軟體模擬結構模態的振頻以及彈簧常數等，透過來回設計的trade-offs考量，得到一個最適當的微掃描鏡架構。
本研究使用TSMC 2P4M 0.35μm CMOS製程，將電磁式微掃描鏡結構、感測電路整合於單一個晶片上，晶片面積6.54 mm × 4.7 mm，另外針對後製程優化，以精準、低成本的方式開發一套完整的後製程流程，經量測過後得到快軸振頻16.389 kHz及慢軸共振頻838 Hz，並驗證壓阻為N-型井的感測度較壓阻為多晶矽的感測度高，動態形變量模擬值(50 nm)也小於1/10的入射光源波長(65 nm)。

關鍵字：電磁式驅動、微掃描鏡、壓阻感測、動態形變量。

Integrated circuit design and silicon chip manufacturing can be integrated considerably under the mature development of the semiconductor industry today. With interdisciplinary research advanced, MEMS integrated circuits are able to integrate on the chip. The micro-scanning mirror chip with sensing is one of the examples. For the desired application in projection display, the motion of the electromagnetically actuated scanning mirror can be detected by piezoresistive polysilicon and N-well sensors deposited on the rotating axis through on-chip readout circuitry.
The deformation of a mirror increases with the rotation speed. This deformation cannot be greater than 1/10 of the wavelength of its incident light, otherwise the imaging position will be incorrect. Therefore the vibration frequency is reduced and the thickness is increased in our design. However, the vibration frequency will also be increased when the thickness is increased. Therefore, it is necessary to increase the length and reduce the width of the spring to effectively reduce the vibration frequency. The result is an increase in the area of the chip. Reducing the vibration frequency also reduces the imaging specifications of the scanning mirror. The strcture modes, spring constant and dynamic deformation are simulated by Ansys finite element analysis software first. The most appropriate micro-scanning mirror structure is obtained by considering the trade-offs of the design.
In this research, the TSMC 2P4M 0.35 μm CMOS process is used to integrate the electromagnetic micro-scanning mirror structure and the sensing circuit on a single chip, with a chip area of 6.54 mm × 4.7 mm. In addition, for post-process optimization, a precise and low-cost method is used to develop a complete set of post-production process. After measurement, the fast-axis resonance frequency is 16.389 kHz and the slow-axis resonance frequency is 838 Hz. It is verified that the sensitivity of piezoresistive N-type well is higher than that of piezoresistive polysilicon, and the dynamic deformation (simulated value = 50 nm) is also less than 1/10 of the incident light source wavelength (65 nm).

Keywords: Electromagnetic Actuation, Micro-scanning mirror, Piezoresistive Sensing, Dynamic Deformation.

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