Towards Ideal Electron‐Transporting Transistor Characteristics in Polymer Semiconductors in Ambient Air

The coexistence of high mobility and ideal current–voltage transistor characteristics is highly desirable for real‐work applications of field‐effect transistors. However, very few high‐mobility polymer transistors can exhibit reliability factors >70%, and even rarer for electron‐transporting devices. In this work, we report a coexistence of a reliability factor of 90% and high mobility of 0.6 cm 2 V −1 s −1 in FBDPPV‐based transistors and, more importantly, systematically investigate the origin by combining optical and microstructural characterizations and transport physics study. We found that in this rigid, coplanar, distortion‐free polymer FBDPPV, efficient charge transport that induces high mobility and near‐ideal transistor behaviors is supported by efficient intrachain transport and limited by energetic disorder along the interchain transport pathway consisting of disorderly connected very small grains. We also compare the structure‐property relationship of FBDPPV with some benchmark high‐mobility polymers and provide insights into rational design strategies for achieving the coexistence of high mobility and ideal current–voltage transistor characteristics.