Enhanced performance of ferroelectric-based all organic capacitors and transistors through choice of solvent

G. Knotts
A. Bhaumik, MSU Graduate Student
Kartik Ghosh, Missouri State University
S. Guha


We examine the role of solvents in the performance of pentacene devices using the ferroelectric copolymer poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFe) as a gate insulating layer. High dipole moment solvents, such as dimethyl sulfoxide (DMSO), used to dissolve the copolymer for spincasting, increase the charge carrier mobility in field-effect transistors by nearly an order of magnitude as compared to lower dipole moment solvents. The polarization in Al/PVDF-TrFe/Au metal-ferroelectric-metal devices is also investigated. An increase in remnant polarization of ∼20% is observed in the sample using DMSO as the ferroelectric solvent. The DMSO based sample shows a hysteresis in its displacement curve even at the lowest measured voltage, indicating that the dipoles in the copolymer are more ordered initially.