S. Sarbada, Y.C. Shin
Keywords: femtosecond laser, nanostructures, superhydrophobic surfaces, microfluidics
Summary:A process to fabricate superhydrophobic surfaces on metals and polymers is presented. Using high speed femtosecond laser pulse irradiation, surface structures have been created on metal surfaces and transferred onto Polydimethylsiloxane (PDMS) to achieve superhydrophobic surfaces. Various surface micro and nano structures are presented and their wetting properties are discussed. Water contact angles of over 150° and contact angle hysteresis of less than 5° were achieved on the textured copper and PDMS surfaces. A fast and inexpensive method to create microfluidic devices with textured superhydrophobic inner channel walls is also presented. These channels allow a controllable fluid flow rate through microfluidic devices. A 186 % increase in fluid flow rate though PDMS microchannels was achieved through the fabrication of hydrophobic structures on the inner channel walls.