Utilizing the Diffusion of Fluorinated Polymers to Modify the Semiconductor/Dielectric Interface in Solution-Processed Conjugated Polymer Field-Effect Transistors

It has been demonstrated that tailoring the properties of semiconductor/dielectric interfaces with fluorinated polymers yields better performance for organic field-effect transistors (OFETs). However, it remains a challenge to fabricate bottom-gate OFET devices on fluorinated dielectrics using solution-processed methods due to the poor wettability of fluorinated dielectrics. Here, we utilized the diffusion of fluorinated poly(methyl methacrylate) (PMMA) to construct the fluorine-rich semiconductor/dielectric interface to achieve the fabrication of bottom-gate OFETs with a solution-processed poly(3-hexylthiophene) (P3HT) semiconductor layer. The consequences indicate that the fluorinated dielectrics can effectively decrease the charge traps density at the semiconductor/dielectric interface and promote the edge-on orientation of P3HT on the dielectric surface. Thus, the devices based on fluorinated PMMA modified dielectrics exhibit higher carrier mobility and electrical stability than those of the fluorine-free devices. Our investigation affords a new strategy for the design and interface optimization of devices, which may further advance the performance of OFET devices.