Digital microfluidics (DMF) enables programmable manipulation of discrete liquid droplets using electrowetting-on-dielectric (EWOD), with applications ranging from lab-on-a-chip systems to adaptive thermal management. Further miniaturization of EWOD platforms requires both high-resolution electrode fabrication and scalable control electronics capable of independently actuating an increasing number of electrodes. This master’s thesis investigates the development of a miniaturized EWOD platform together with compact and scalable droplet-control systems. A 4 × 4 gold electrode array with 1 × 1 mm electrodes, 40 μm inter-electrode gaps and 5 μm interconnects was fabricated using maskless photolithography, followed by deposition of a 15 μm SU-8 dielectric layer and a FluoroPel hydrophobic coating. Single- and multi-electrode actuation was evaluated using transistor-based control circuits and an integrated 32-output control board, while a dedicated AC switching system was developed for droplet splitting. Under DC actuation, droplet splitting was limited to incomplete necking and pronounced surface pinning even at 235 V. In contrast, a symmetric 3 kHz AC square-wave signal enabled repeatable droplet splitting in a closed EWOD configuration at an applied voltage of 142 V. During droplet transport, the maximum measured velocity reached approximately 145 mm/s at 190 V and showed a plateau at higher actuation voltages. The integrated 32-output board eliminated the need for an external high-voltage power supply and amplifier, although serial communication introduced an inter-electrode switching delay of approximately 120 ms. The developed platform provides a compact experimental basis for further development of miniaturized and scalable EWOD systems for lab-on-a-chip and adaptive thermal-management applications.
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