一般而言，微掃描面鏡通常以靜電方式驅動最為常見，其應用極為廣泛。舉例而言，德州儀器公司（Texas Instruments）所發展的DMD，光纖通訊中的switch及shutter ，乃至於應用在眼科手術或光線對準器上，都需要微掃描面鏡其所需要的功能。一般而言，以表面微加工方式製造的此型致動器，因為結構剛性的限制，多會產生一些鏡面不平整或操作時的鏡面變形等問題，雖然經由一些疊層或結構的設計，可減少這些鏡面的問題，但已有愈來愈多的研究者，直接改以體型微加工方式來增加結構的厚度，以有效地增加此型微掃描面鏡的鏡面剛性。
本研究主要是藉由一種高深寬比的BELST（111）矽晶片製程，製造出高剛性大出力大運動量之厚結構微致動器，再利用製程改進來達到厚度局部調整的結構，進而產生致動器與扭轉軸的不同厚度，如此一來，便可以分別降低扭轉剛性及提高垂直梳狀致動器所需的行程量，另外，再加上藉由商用軟體MEMCAD的模擬結果，所製作出具最佳出力的垂直梳狀致動器，就可製作出符合低頻高掃描角度或高頻高光學解析度的垂直靜電驅動微掃描面鏡。由於BELST製程容易、加上位移量大以及光學品質佳等優點，將可應用於光纖通訊、顯示器、投影系統、以及光掃描器等等。

Angular motion plays a crucial role in optical applications such as switching and scanning. The angular motion is available using electrostatic actuation like parallel plate, lateral comb, and vertical comb. Among them the vertical comb actuator (VCA) is regarded as the most promising approach to provide large angular motion. Recently, the High-Aspect-Ratio micromachining (HARM) process have demonstrated their importance of offering even large angular motion as well as extremely stiffness micro-structures. However, these approaches may suffer from alignment and bonding processes.
A HARM process using (111) silicon wafer is proposed in this study to fabricate a vertical comb drive actuator and a micro scanning mirror. Moreover, a large yet stiff mirror and a thin torsional spring are also available through the Extended BELST process within three masks. Thus the optical performance is improved and the driving voltage is reduced. A high-aspect-ratio micro scanner embedded with vertical comb actuator, 500×500mm2 flat mirror, and trimmed torsional springs is successfully fabricated. The static and dynamic performances of micro scanner are also measured.

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