Influence of surface passivation techniques towards the realization of high-responsivity organic phototransistors

Abstract

Organic phototransistors (OPTs) have gained significant attention as next-generation light sensing devices because of their low-cost fabrication, mechanical flexibility, lightweight structure, and compatibility with large-area solution processing techniques. These advantages make them attractive for applications such as wearable sensors, flexible imaging systems, smart electronics, environmental monitoring, and biomedical devices. However, despite their potential, the practical use of OPT is still limited by its relatively lower charge carrier mobility and stability. Developing highly e!cient OPT requires a deeper understanding of the relationship between material properties, thin film morphology, charge transport, and interface engineering. Molecular ordering, charge carrier mobility, dielectric surface passivation, exciton separation, and electrode contact are the crucial factors determining device performance. In this work, we fabricated polymer thin films using a cost- effect solution processable method called unidirectional-floating film transfer method (U-FTM), as unidirectional alignment of CP macromolecules is extremely desired for the facile in-plane charge transport along the orientation direction to improve the performance of the OPTs.