Development and characterization of a novel configurable MEMS inertial switch using a microscale liquid-metal droplet in a microstructured channel

Abstract This paper presents the development and characterization of a novel microelectromechanical systems (MEMS) inertial switch that uses a microscale liquid-metal (LM) droplet in a microstructured channel as the active component. Our inertial switch made use of the advantageous properties of the LM droplet ( i.e. , high surface tension, high density, and electrical conduction) and the microstructured surface. The channel surface was selectively modified to form microstructures that enhanced the non-wetting behavior while minimizing the contact angle hysteresis (CAH) of the LM droplet on the surface. Integrating the LM droplet, which was used as an inertial-proof mass, inside the configured channel containing microstructures on the surface, an inertial switch with a dramatically simplified, yet effective, mechanism was realized. Various channel configurations can be designed for different threshold levels of acceleration.

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