The Influence of a Microstructural Conformation of Oriented Floating Films of Semiconducting Polymers on Organic Device Performance

Abstract

Extended π-conjugation with backbone-planarity-driven π-π stacking dominates charge transport in semiconducting polymers (SCPs). The roles of SCP film morphology and macromolecular conformation concerning the substrate in influencing charge transport and its impact on device performance have been a subject of extensive debate. Face-on SCPs promote out-of-plane charge transport primarily through π-π stacking, with conjugated polymeric chains assisting transport in connecting crystalline domains, whereas edge-on SCPs promote in-plane charge transport primarily through conjugation and π-π stacking. In this work, we fabricated three different types of devices, namely, organic field effect transistors, organic Schottky diodes, and organic bistable memristors, as representatives of planar and vertical devices. We demonstrate that a planar device, i.e., an organic field effect transistor, performs well in an edge-on conformation exhibiting a field-effect mobility of 0.12 cm2V−1s−1 and on/off ratio >104, whereas vertical devices, i.e., organic Schottky diodes and organic memristors, perform well in a face-on conformation, exhibiting exceptionally high on/off ratios of ~107 and 106, respectively.

Photoelectronic synaptic transistors with tuneable synaptic plasticity based on films of P3HT with ordered polymer chains

“…At the present time most organic optoelectronic synaptic transistors are based on the use of amorphous semiconductors films [27][28][29]. However, transistors based on alignment films [30][31][32] and single crystals [33] show higher carrier mobility compared to that of amorphous films. In turn this leads to improvements in the performance of these devices.…”