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Packaging of In-Plane Micro-Actuators for BioMEMS Applications



Hrishikesh V. Panchawagh, David Serrell, Faheem F. Faheem, Cari F. Herrmann, Dudley Finch, Roop L. Mahajan


Two issues related to actuation of in-plane, electro-thermal actuators for BioMEMS applications are addressed. First, a packaging solution to protect the actuator from biological debris and particulates by encapsulating the actuator with a cap using flip-chip bonding is demonstrated. The motion was transferred from encapsulated actuator to the outside via a piston, which moved through a small clearance. The other issue we addressed is the reduction in thermal actuator efficiency in liquids. By coating the encapsulation with a thin hydrophobic layer via atomic layer deposition (ALD), the liquid was prevented from entering inside the encapsulation. This avoided a direct contact of the liquid with the thermal actuator and therefore improved its efficiency. A water-resistant epoxy was applied on the packaged actuators using micro-manipulator to cover the etch-holes in the cap and provide good bonding. Un-packaged and packaged thermal actuators were submerged in de-ionized water and tested. Although, the thermal actuator performance was slightly affected by the package in air, the actuator efficiency in water was improved due to isolation of the thermal actuator hot arms from water. This encapsulation is also applicable to protect electrostatic comb drive actuators, although there is no need of liquid sealing in this case.
Proceedings Title
Microtechnologies inb Medicine and Biology
Conference Location
Oahu, HI, USA
Conference Title
IEEE - EMBS - MMB 2005


hydrophobic coating, atomic layer deposition, encapsulation, flip-chip, PolyMUMPs, sealing, thermal actuator


Panchawagh, H. , Serrell, D. , Faheem, F. , Herrmann, C. , Finch, D. and Mahajan, R. (2005), Packaging of In-Plane Micro-Actuators for BioMEMS Applications, Microtechnologies inb Medicine and Biology, Oahu, HI, USA, [online], (Accessed April 18, 2024)
Created November 4, 2005, Updated October 12, 2021