Ultra-large-scale active-matrix digital microfluidic system integrated with droplet position sensing and AI automatic path planning

This paper presents an ultra-large-scale low temperature poly-silicon (LTPS)-based active-matrix digital microfluidic (AM-DMF) chip, featuring 900 × 1200 pixels, marking the first-ever reported million-scale AM-DMF chip. Novel channel thin-film transistors (TFT) are used in pixel circuits to suppress leakage current, thereby improving droplet actuation efficiency and enabling the minimum controllable droplet volume of 1.2 nL. A capacitance-based droplet position sensing module is co-integrated within each pixel and a priority-based A-star (PBA*) path-planning algorithm is employed to support real-time routing of large-scale droplets, establishing a robust closed-loop control framework. This work not only demonstrates the feasibility of extending TFT to non-display applications but also opens new avenues for high-throughput on-chip liquid biological samples processing.