Nano Research

, Volume 1, Issue 4, pp 341–350 | Cite as

Interfacial charge transfer in nanoscale polymer transistors

  • Jeffrey H. Worne
  • Rajiv Giridharagopal
  • Kevin F. Kelly
  • Douglas Natelson
Open Access
Research Article

Abstract

Interfacial charge transfer plays an essential role in establishing the relative alignment of the metal Fermi level and the energy bands of organic semiconductors. While the details remain elusive in many systems, this charge transfer has been inferred in a number of photoemission experiments. We present electronic transport measurements in very short channel (L < 100 nm) transistors made from poly(3-hexylthiophene) (P3HT). As channel length is reduced, the evolution of the contact resistance and the zero gate voltage conductance are consistent with such charge transfer. Short channel conduction in devices with Pt contacts is greatly enhanced compared to analogous devices with Au contacts, consistent with charge transfer expectations. Alternating current scanning tunneling microscopy (ACSTM) provides further evidence that holes are transferred from Pt into P3HT, while much less charge transfer takes place at the Au/P3HT interface.

Keywords

Organic semiconductors band alignment charge transfer organic field-effect transistor scanning tunneling microscopy 

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Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Jeffrey H. Worne
    • 1
  • Rajiv Giridharagopal
    • 1
  • Kevin F. Kelly
    • 1
  • Douglas Natelson
    • 1
    • 2
  1. 1.Department of Electrical and Computer EngineeringRice UniversityHoustonUSA
  2. 2.Department of Physics and AstronomyRice UniversityHoustonUSA

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