292 / 2024-10-14 18:57:11

Research on the Feasibility of Microswitches Based on Electrowetting on Dielectric Technology

microswitch,electrowetting on dielectric,Galinstan,contact angle

Traditional mechanical switches suffer from shortcomings such as Holm force, high contact resistance, contact wear, and welding defects, hindering their performance improvement. Galinstan, a non-toxic liquid metal at room temperature, can replace solid contacts in traditional switches, transforming solid-to-solid contact into solid-to-liquid contact, significantly improving the shortcomings of traditional mechanical switches and offering broad application prospects. This paper proposes a concept of a micro switch based on electrowetting on dielectric (EWOD) technology, where applying a driving voltage induces deformation of Galinstan droplets, thereby achieving main circuit conduction. To verify its feasibility, the electrowetting on dielectric of Galinstan droplets was simulated using Comsol Multiphysics^®. Different driving voltages were applied between the droplets and the driving electrodes, obtaining the movement distance of the three-phase line, the droplet motion time and the contact angle. The short motion time and sufficient movement distance meet the conditions for switch fabrication. An experiment on electrowetting on dielectric was designed. The contact angle and three-phase line movement distance of the droplets under different driving voltages were measured on a contact angle measuring instrument. The small deviation between the obtained results and the simulation outcomes validates the rationality of the simulation. The conclusion of this paper provides a theoretical basis for further designing and manufacturing micro switches based on electrowetting on dielectric technology.