Photomultiplication‐Type Organic Photodetectors: Mechanisms, Integration Toward Next‐Generation Sensing Platforms

Abstract Photomultiplication‐type organic photodetectors (PM‐OPDs) have garnered considerable attention for their ability to provide high sensitivity and tunable spectral response, positioning them as promising candidates for next‐generation optoelectronic applications. These detectors leverage internal gain mechanisms, enabling external quantum efficiencies (EQE) surpassing the traditional limit of 100%. This review systematically explores the operational principles of PM‐OPDs, focusing on charge carrier dynamics, with an emphasis on trapping mechanisms, and highlights the latest advancements in materials and device architectures. Key areas of exploration include bulk heterojunction traps, interface‐induced carrier trapping, and the role of carrier‐blocking layers in enhancing device performance. Functionalized PM‐OPDs, including narrowband, dual‐band, and dual‐mode, are discussed, emphasizing their innovative designs for spectral selectivity and operational versatility. Moreover, the application potential of PM‐OPDs is explored across various domains, including bio‐sensing, low‐light imaging, optical communication, and miniaturized spectroscopy. Despite their promise, challenges related to noise performance, response speed, operating voltage, and long‐term stability are remaining barriers. The outlook suggests continued advancements in material engineering, device optimization, and integration with flexible platforms. This review serves as a comprehensive guide to the current state of PM‐OPDs and identifies future research directions to address the existing limitations and unlock new opportunities for their application scenarios.