The authors study temperature dependent electrical transport in pristine and tetrafluorotetracyanoquinodimethane -doped pentacene to explore the physical mechanism of the doping-induced reduction in the contact resistance at the metal-organic semiconductor interface. It was found that the -doping induces an apparent lowering of the hole injection barrier at gold-pentacene interfaces. In addition, characteristic changes in the density of states (DOS) induced by the -doping in a thin-film transistor geometry have been observed. The correlation between the doping-induced DOS and the carrier injection process is discussed.
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2009
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