Vanoni, Claudio. Electronic transport, field effect and doping in pentacene nanorods and monolayer thin film prepared by combination of nano-fabrication and self-assembly. 2008, PhD Thesis, University of Basel, Faculty of Science.
Official URL: http://edoc.unibas.ch/diss/DissB_8446
of the DOS in doped TFTs shows an additional broad peak
at 0.14 eV above the HOMO edge caused by the dopant molecules.
A second pronounced effect of doping is the reduction of the
Rc by a factor 20 between the gold electrode and pentacene. The
gate field dependent decrease of Rc in undoped TFTs is related to
a lowering of the Schottky barrier at the interface. In doped TFTs,
the opposite effect is observed. This demonstrates the influence of
the dopant molecules on the interface barrier. The injection process
determining Rc is found to change from a thermionic emission
mechanism to a tunneling regime.
For the investigation of the injection properties at the interface,
a new manufacturing method to produce metallic nanojunction is
presented. In combination with a self-assembly process leading to
pentacene rod-like islands connecting the two electrodes right through
their growth, the transport in the 10-nm scale is investigated. At this
scale length, the current-voltage (I-V) characteristics of pentacene is
changing from rectifying Schottky-like behavior to fully linear behavior
upon F4TCNQ doping. Variable temperature investigations show
that the conduction in the doped pentacene nanojunction is thermally
activated, with an activation energy very close to the energy
position of the dopant induced peak in the DOS and to the thermal
activation energy of Rc.
|Committee Members:||Jung, Thomas Andreas and Riess, Walter|
|Faculties and Departments:||05 Faculty of Science > Departement Physik > Physik > Experimentalphysik Nanoeklektronik (Schönenberger)|
|Bibsysno:||Link to catalogue|
|Number of Pages:||169|
|Last Modified:||30 Jun 2016 10:41|
|Deposited On:||13 Feb 2009 16:44|
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