The master’s thesis presents the design, fabrication, and analysis of a digital microfluidic device for droplet manipulation based on electrowetting, featuring single-layer electrode architecture with contact lines. The focus is on the experimental work, which includes automated droplet movement experiments conducted using an algorithm. The theoretical foundations required to understand the phenomenon of electrowetting and the applications of electrowetting-on-dielectric (EWOD) technology are described at the beginning. The experimental section details the design and fabrication of electrodes using laser photolithography and the surface preparation process, where dielectric and hydrophobic layers were applied using spin-coating techniques. Measurements of static contact angles and droplet movements were performed, with the results presented subsequently. The functionality of the proposed concept with operational central electrodes was confirmed. The fabricated device exhibits a saturation voltage threshold of 230 V, enables high droplet contact angles above 120°, and allows for a contact angle variation of 24.5°. On a 15 µm dielectric layer, a droplet speed of approximately 68 mm/s was achieved at 140 V. The thesis also includes proposals for further work and suggested improvements to the manifacturing process or conceptual design.
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