Thermionic Emission and Tunneling at Carbon Nanotube-Organic Semiconductor Interface

    Authors

    B. K. Sarker;S. I. Khondaker

    Comments

    Authors: contact us about adding a copy of your work at [email protected]

    Abbreviated Journal Title

    ACS Nano

    Keywords

    carbon nanotube electrodes; organic semiconductor; charge injection; barrier height; thermionic emission; Fowler-Nordheim tunneling; direct; tunneling; FIELD-EFFECT TRANSISTORS; ENERGY-LEVEL ALIGNMENT; THIN-FILM TRANSISTORS; CHARGE INJECTION; ELECTRODES; METAL; POLYMER; NANOWIRES; MOLECULES; DEVICES; Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience &; Nanotechnology; Materials Science, Multidisciplinary

    Abstract

    We study the charge carrier injection mechanism across the carbon nanotube (CNT)-organic semiconductor interface using a densely aligned carbon nanotube array as electrode and pentacene as organic semiconductor. The current density-voltage (J-V) characteristics measured at different temperatures show a transition from a thermal emission mechanism at high temperature (above 200 K) to a tunneling mechanism at low temperature (below 200 K). A barrier height of similar to 0.16 eV is calculated from the thermal emission regime, which is much lower compared to the metal/pentacene devices. At low temperatures, the J-V curves exhibit a direct tunneling mechanism at low bias, corresponding to a trapezoidal barrier, while at high bias the mechanism is well described by Fowler-Nordheim tunneling, which corresponds to a triangular barrier. A transition from direct tunneling to Fowler-Nordheim tunneling further signifies a small injection barrier at the CNT/pentacene interface. Our results presented here are the first direct experimental evidence of low charge carrier injection barrier between CNT electrodes and an organic semiconductor and are a significant step forward in realizing the overall goal of using CNT electrodes in organic electronics.

    Journal Title

    Acs Nano

    Volume

    6

    Issue/Number

    6

    Publication Date

    1-1-2012

    Document Type

    Article

    Language

    English

    First Page

    4993

    Last Page

    4999

    WOS Identifier

    WOS:000305661300047

    ISSN

    1936-0851

    Share

    COinS
     

    Accessibility Statement

    This item was created or digitized prior to April 24, 2027, or is a reproduction of legacy media created before that date. It is preserved in its original, unmodified state specifically for research, reference, or historical recordkeeping. In accordance with the ADA Title II Final Rule, the University Libraries provides accessible versions of archival materials upon request. To request an accommodation for this item, please submit an accessibility request form.