Side-chain engineering as a powerful tool to tune the properties of polymeric field-effect transistors

During the past ten years, the performance of polymeric field-effect transistors has been largely improved, not only in mobility but also in durability. Among the factors contributed to such improvements, side-chain engineering plays an important role. Various techniques, such as branch point adjustment, hydrogen-bonding introduction and the incorporation of other functional groups in the side-chain were developed, which greatly altered the crystallinity, alignment and morphology of the conjugated polymers hence their charge transport behavior. In this review, the side-chain engineering strategies that have been employed in polymeric field-effect transistors are summarized and discussed in detail, which we hope could provide an insight into further development in this area.