A combined ElectroWetting on Dielectrics superhydrophobic platform based on silicon micro-structured pillars

Abstract

A simple and ready to use approach for combining silicon superhydrophobic surfaces with ElectroWetting On Dielectrics (EWOD) phenomenon is presented. The substrate is fabricated using a two-phases process, where a first optical lithography step is used to define the position of the micro-pillars and a second one exploits the characteristics of reactive ion etch Bosch technique. The fabricated substrate has been then coupled with a micro-manipulator tip to show the local changes mechanism of contact angle by applying very low DC voltages in the range from 5 to 30 V. The device can be of interest for a wide variety of microfluidics applications related to the biomedical field