聚雙甲基矽氧烷(PDMS)為彈簧之異質整合靜電式垂直梳狀致動器

A hybrid vertical comb-drive actuator supported by flexible poly-dimethylsiloxane (PDMS) suspensions

李玥瑩(Lee, Moonwin)

指導教授 ： 陳榮順

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2011年)

https://doi.org/10.6843/NTHU.2011.00031

摘要

本論文主要在發展高分子異質整合技術。希望提供一個採用現有製程技術，將低楊氏係數之高分子元件做為彈簧，搭載於高剛性之矽基致動結構，無需額外高分子製程再對準或接合於矽基結構，達到最大異質整合之目的。本研究以靜電式垂直梳狀致動器為例，展現此異質整合技術的可行性。在SOI晶圓正面，深蝕刻做好高分子PDMS彈簧母模；待PDMS填入母模後，再深蝕刻完成矽基梳狀致動器；最後於SOI晶圓背面，以深蝕刻做懸浮腔體。當移除犧牲氧化層，完成懸浮後，動子因自身重量而自然下墜。當動子重量與支撐動子的PDMS彈簧達到力平衡後，梳狀致動器自然達成初始垂直斷差。此製程能使異質整合同步完成，自我對準，亦無後續機制加工或是特殊元件設計造成段差。此元件將展現異質整合優點，因柔軟的PDMS連結矽基致動器後，有機械性質增益；矽基致動器因低剛性高分子做為彈簧，有大初始垂直斷差與低驅動電壓的增益。此外，PDMS較不利於水平作動，所以在垂直方向上，更能發揮特性，使致動器在低電壓輸入下得到高效能的垂直作動。製作之400/20 μm彈簧元件在45 Vdc下為2.985 μm的位移量(0.066 μm/Vdc)，在25 Vac 3532.5 Hz為3.731 μm的位移量；200/25 μm彈簧元件在50 Vdc下為0.8741 μm的位移量(0.0174 μm/Vdc)，在35 Vac 3537.5 Hz為2.116 μm的位移量。

關鍵字

垂直梳狀致動器 ； 異質整合 ； PDMS ； 高分子

並列摘要

We introduced a hybrid PDMS-silicon electrostatic actuator with a large stroke under low driving voltages. The device features a staggered vertical comb-drive suspended by PDMS springs. Because of the flexibility of PDMS, an initial staggered displacement was naturally formed due to the self-weight of the device. Experimental results showed the combination of polymeric springs and silicon structures enabled the large stroke of 3.73 μm at 3.5 kHz. The presented heterogeneous integration technology improves the performance and may bring new functionalities to micro-systems.

並列關鍵字

vertical comb drive ； hybrid ； PDMS ； polymer

參考文獻

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