Organic Heterojunction Transistors Based on DEP‐DTT Isomers and PTCDI‐CH2C3F7

Abstract Organic heterojunction transistors (OHJTs) are fabricated with three isomers, DEP‐ bb ‐DTT, DEP‐ bt ‐DTT, and DEP‐ tt ‐DTT as p‐type semiconductors, and PTCDI‐CH 2 C 3 F 7 as n‐type semiconductor. All the OHJTs present n‐channel and ambipolar operating modes in turn with the thickness ( t ) of the isomers films increasing. The properties of p‐type semiconductors directly affect the performances of OHJTs. The amplitude variation of the highest field‐effect mobilities for holes (μ h ) and electrons (μ e ) in OHJTs is consistent with that of μ uni in their unique OFETs. The μ e in DEP‐ bb ‐DTT/PTCDI‐CH 2 C 3 F 7 OHJTs present flipped V‐shaped behaviors, while they show the upright and inverted V‐shaped combination patterns in DEP‐ bt ‐DTT/PTCDI‐CH 2 C 3 F 7 and DEP‐ tt ‐DTT/PTCDI‐CH 2 C 3 F 7 OHJTs. By analyzing these p‐type isomers pristine and annealed films, a transformation from monolayer to bilayer occurring in the initial growth course of the DEP‐ bt ‐DTT and DEP‐ tt ‐DTT films is discovered and responsible for the variation tendencies of μ e . The layers of the p‐type materials films are responsible for the occasions of the highest μ h and μ e emerging.