High electron mobility in nano-composite thin film transistors

Researchers from the London Centre for Nanotechnology (Professor Arokia Nathan & al.) and Cambridge University demonstrate extremely high electron mobility in nano-composite thin film transistors using zinc oxide and organic semiconductors.

Organic semiconductors can offer an alternative to amorphous silicon for many large area and flexible electronics applications by virtue of their solution processability. However, they are often limited by their significantly lower field-effect mobility, with high-performance n-type devices proving a particular challenge. This work uses a technique for combining zinc oxide (ZnO) nanostructures synthesized using vapor phase deposition with organic semiconductors to create nano-composite thin film transistors with the highest reported electron field-effect mobility in solution processed devices.

A dispersion of ZnO nanorods in an n-type organic semiconductor ([6, 6]-phenyl-C61-butyric acid methyl ester, PCBM) are shown to enhance the electron field effect mobility by as much as a factor or 40 from the pristine state. The results although preliminary, show a highly promising enhancement for realization of high-performance solution-processable n-type organic TFTs.

Journal Link:  IEEE Trans. Electron Devices, 55 (2008) 3001