Investigation of anti-stiction coating using π-conjugated hydrophobic self-assembled monolayer for ohmic contact MEMS switch

This article discusses anti-stiction coating with conductive self-assembled monolayer (SAM) for ohmic contact microelectromechanical system (MEMS) switches. As we reported in the previous study, capillary force is a dominant factor of stiction in the air, and a hydrophobic SAM and Au coating can reduce the capillary force by preventing the formation of the liquid meniscus. In this study, we measured adhesion force and contact resistance for π-conjugated hydrophobic SAM deposited on Au, and compared it with that of σ-bonds formed hydrophobic SAM and Au sample surfaces. Our measurements indicate that π-conjugated hydrophobic SAM is effective in preventing stiction for ohmic contact MEMS switches with low-load contact.

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