Work Function Independent Hole-Injection Barriers Between Pentacene and Conducting Polymers


  • The authors thank Dr. K. Reuter (H. C. Starck, Leverkusen) for kindly providing PEDT-S and helpful discussions. The synchrotron work was supported by the IHP-Contract HPRI-CT-1999-00040 of the European Commission. We thank Prof. J.-J. Pireaux and Dr. J. Ghijsen for providing experimental equipment.


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The energy level alignment (see Figure) at interfaces between pentacene and thin films of conducting polymers (made from ethylenedioxythiophene and sulfonate moieties) is found to be independent of initial polymer work function or morphology. Interfacial chemical reactions control the energy level alignment, rather than just the pristine substrate work function.