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arXiv · cond-mat/0403210

Hole mobility in organic single crystals measured by a "flip-crystal" field-effect technique

Abstract

We report on single crystal high mobility organic field-effect transistors (OFETs) prepared on prefabricated substrates using a "flip-crystal" approach. This method minimizes crystal handling and avoids direct processing of the crystal that may degrade the FET electrical characteristics. A chemical treatment process for the substrate ensures a reproducible device quality. With limited purification of the starting materials, hole mobilities of 10.7, 1.3, and 1.4 cm^2/Vs have been measured on rubrene, tetracene, and pentacene single crystals, respectively. Four-terminal measurements allow for the extraction of the "intrinsic" transistor channel resistance and the parasitic series contact resistances. The technique employed in this study shows potential as a general method for studying charge transport in field-accumulated carrier channels near the surface of organic single crystals.

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BibTeXRIS

C. Goldmann, S. Haas, C. Krellner, K. P. Pernstich, D. J. Gundlach, B. Batlogg. 2004-03-08. Hole mobility in organic single crystals measured by a "flip-crystal" field-effect technique. https://doi.org/10.1063/1.1767292

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