Modulating Charge Transport from Thermally Activated to Band-Like Through Interfacial Bottom-Up Binding Capability of Bilayer Polymer Dielectrics

The disordered chain arrangement of polymer dielectrics has complex both internal and external effects on system performance, which generally stimulates the weak acquisition and grain boundaries of vapor-deposited organic small molecule films (VDOSMFs) with thermally activated charge transport. As a result, achieving band-like transmission of VDOSMs on polymer dielectrics is attempting to prove to be a major challenge. Three types of bi-polymer dielectrics are developed to modulate charge transport from thermally activated mode to band-like transport at the interfacial level. The bottom consisting of a polyimide layer is critical to interfacial modulation, which shows the selectively binding capability with up-dielectric layers to realize the modulation of charge transport, as corroborated by interface characterization and density functional-based tight-binding calculation. The findings provide an effective strategy for modulating the charge transport through polymer dielectric engineering and also recommend a podium to further comprehend the electrical characteristics of small molecules in organic thin-film transistors.

Automated summary

The disordered chain arrangement of polymer dielectrics affects the system performance, making it difficult to achieve band-like transmission of vapor-deposited organic small molecule films (VDOSMFs). In this study, three types of bi-polymer dielectrics were developed to modulate charge transport from thermally activated mode to band-like transport at the interfacial level. The polyimide layer in the bottom plays a crucial role in interfacial modulation, selectively binding with the up-dielectric layers to control charge transport.