Stretchable Organic Photodetectors: From Structural to Intrinsic Design

Stretchable organic photodetectors (OPDs) have emerged as key components for next-generation human-centric optoelectronics, enabling conformal sensing, wearable health monitoring, and soft-machine interfaces. While organic semiconductors offer mechanical compliance and versatile optoelectronic tunability, achieving stable photodetection under mechanical deformation remains a fundamental challenge due to the intrinsic trade-off between molecular ordering and mechanical softness. Early efforts primarily relied on structural strain-relief strategies, such as buckling geometries and island–bridge layouts, which mitigate mechanical stress but introduce limitations in scalability, device density, and design flexibility. Recent advances have shifted the focus toward intrinsically stretchable material systems, where mechanical deformability is embedded at the material level through molecular engineering and elastomer–semiconductor composite strategies. In particular, the integration of elastomer networks with semiconducting pathways has enabled new opportunities to simultaneously maintain charge transport continuity and suppress dark current under strain. This review provides a comprehensive overview of stretchable OPDs, emphasizing the transition from structural to intrinsic design strategies. We first discuss the operating principles of OPDs and the impact of mechanical deformation on key performance metrics, including responsivity and detectivity. We then examine recent advances in molecular design, composite systems, morphology engineering, and device architecture. Finally, we highlight emerging applications and outline critical challenges for future development of intrinsically stretchable photodetection systems.<br /><br />