Flexible Field-Effect Transistor Sensors for Next-Generation Health Monitoring: Materials to Advanced Applications

Flexible field-effect transistor (FET) sensors have emerged as a promising technology for human health monitoring, driven by breakthroughs in materials, device design, and fabrication processes. Their unique advantages, including multi-parametric detection, intrinsic signal amplification, low power consumption, and scalable production, position them at the forefront of wearable and implantable biosensing systems. This review outlines the structural design and operational principles of flexible FET sensors, systematically summarizing material innovations for critical components (substrates, dielectrics, semiconductor channels, and electrodes) and strategies to harmonize electrical performance with mechanical robustness. It analyzes evaluation methods and optimization strategies for enhancing mechanical stability under repetitive strain, a pivotal challenge for practical deployment. Additionally, it highlights cutting-edge applications in physiological signal monitoring and biological fluid analysis, demonstrating their potential for real-time diagnostics. Finally, the review discusses the current limitations of flexible FET sensors and provides an outlook on their future opportunities in personalized health management, intelligent diagnostic systems, and next-generation medical technologies.