Low-Power Unipolar TFT Circuits for Flexible Electronics

The growing demand for affordable, flexible, and energy-efficient electronics for displays, wearables, and IoT systems has renewed interest in thin-film transistor (TFT) circuits. However, most TFT technologies are unipolar, posing challenges for complex logic implementation due to restricted output swing and excessive direct-path current. In this work, we present a comprehensive design methodology for low-power digital circuits using unipolar TFTs, addressing both static power dissipation and robustness under mechanical strain. We first demonstrate low-power logic gates and D flip-flops (DFFs) that significantly suppress direct-path current while achieving full-swing outputs. Circuits were fabricated on both glass and flexible substrates, and their performance under tensile and compressive bending was experimentally validated. Results show that the proposed circuits reduce power consumption by more than 55% compared to other designs, with negligible degradation under bending stress. To evaluate system-level applicability, a bit-serial arithmetic logic unit (ALU) was simulated as a benchmark, demonstrating power savings up to 45% compared to state-of-the-art designs. These results establish a practical pathway for integrating low-power logic and sequential circuits directly on flexible backplanes, reducing reliance on off-panel CMOS and enabling future generations of low-power displays, IoT devices, and conformable electronics.