Rapid prototyping of low-cost digital microfluidic devices using laser ablation

Abstract

In this paper, a simple, low-cost, and fast prototyping method is presented for digital microfluidics (DMFs) fabrication. In the proposed method, commercial Polymethyl methacrylate (PMMA) sheets are used as the substrate, and a desktop diode laser engraver has replaced photolithography for electrode patterning. The proposed maskless method is capable of forming the DMF electrodes with ~100µm spacing. Engraved patterns are filled with a conductive paste like Silver paste to form electrodes. A thin layer of Polydimethylsiloxane (PDMS) and Bio-Oil® are exploited as dielectric and hydrophobic layer, respectively. Fabricated devices were successfully tested for droplet manipulation and mixing which shows that this method can be a rapid and low-cost alternative for conventional fabrication techniques.