Fabrication of high-mobility organic single-crystal field-effect transistors with amorphous fluoropolymer gate insulators

doi:10.1016/j.orgel.2008.05.008

Organic Electronics

Volume 9, Issue 5, October 2008, Pages 753-756

https://doi.org/10.1016/j.orgel.2008.05.008 Get rights and content

Abstract

High-mobility rubrene single-crystal field-effect transistors are built on highly water- and oil-repellent fluoropolymer gate insulators. Roughness is introduced at the surface once to provide good adhesion to metal films and photoresist polymers for stable electrodes. Before constructing interfaces to crystals, smoothness of the fluoropolymer surface is recovered by annealing at a moderate temperature to maximize carrier mobility. Mobility values estimated in the saturation region reproducibly exceeded 15 cm²/V s for all the 10 devices, reaching 30 cm²/V s for the best two devices. The results demonstrate that the water-repellency and smoothness of the dielectric polymers are favorable for the excellent transistor performance.

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Acknowledgements

The authors acknowledge Asahi Glass Company for technical information on Cytop^TM. This work was financially supported by the Industrial Technology Research Grant Program in 2006 of NEDO, Japan, and a Grant-in-Aid for Scientific Research (Nos. 17069003, 18028029, and 19360009) from MEXT, Japan.

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Fabrication of high-mobility organic single-crystal field-effect transistors with amorphous fluoropolymer gate insulators

Abstract

Section snippets

Acknowledgements

Org. Electr.

J. Cryst. Growth

Adv. Mater. (Weinheim, Germany)

Appl. Phys. Lett.

J. Appl. Phys.

Appl. Phys. Lett.

Phys. Rev. Lett.

Jpn. J. Appl. Phys.

Phys. Rev. Lett.