The research in semiconducting polymers for use as transistors is focused on the charge transport physics of organic semiconductors, and their application in field-effect transistor devices fabricated by solution-processing and direct printing techniques.
Many properties of polymer semiconductor depend on the transport of charges along the polymer backbone and from one polymer chain to another polymer chain. Field-effect transistors are a convenient tool for studying these charge transport processes in conjugated polymers. Charges in polymers experience a strong electron-phonon coupling and tend to form so-called polarons. The transport of these polarons is in many respects similar to the electron transfer processes that occur in biological processes such as photosynthesis, and we have developed a number of experimental techniques to study these processes on a molecular scale.
Major areas of current research include:
- Charge transport and device physics of organic semiconductors
- Scanning probe characterization of nanoscale charge transport
- High resolution and self-aligned printing for micro- and nanofabrication
- Study of n-type and ambipolar transport in organic semiconductors and recombination in light-emitting field-effect transistors
The devices constructed using the printing technology have resulted in high performance organic transistors on a length scale of 100 nm. These innovations are being exploited by the successful spin-off company Plastic Logic.