Strain-induced aggregate state instability in organic semiconductor (OSC) films is a critical and bottleneck issue in the practicalization process of organic field-effect transistors (OFETs), but this issue lacks deep insight and effective solutions for a long time. Herein, we developed a novel and general strain balance strategy for stabilizing the aggregate state of OSC films and enhancing the robustness of OFETs. The charge transport zone in OSC films located at the OSC/dielectric interface always suffers from the intrinsic tensile strain induced by substrates and tends to dewet. By introducing a compressive strain layer, the tensile strain can be well balanced and OSC films attain a highly stable aggregate state. Consequently, the OFETs based on strain-balanced OSC heterojunction films exhibit excellent operational and storage stability. This work provides an effective and general strategy to stabilize OSC films and gives guidance in constructing highly stable organic heterojunction devices.
Keywords: aggregate state; film strain; organic field-effect transistor; organic semiconductor; stability.