Dresden 2017 – wissenschaftliches Programm
CPP 21: Organic Electronics and Photovoltaics III: Mobile and Trapped Charges (joint session CPP/DS/HL, organized by CPP)
CPP 21.6: Vortrag
Dienstag, 21. März 2017, 10:45–11:00, ZEU 260
Controlling the transport in organic electronics via self-assembled Monolayers — •Anja Förster1, Sibylle Gemming2,3, and Gotthard Seifert1 — 1TU Dresden, Center for Advancing Electronics Dresden (cfaed), 01062 Dresden, Germany — 2Institute of Ion Beam Physics and Material Research, Helmholtz-Zentrum Dresden Rossendorf, Center for Advancing Electronics Dresden (cfaed), Bautzner Landstr. 400, 01328 Dresden, Germany — 3Insitute of Physics, TU Chemnitz, 09107 Chemnitz, Germany
Self-assembled monolayers (SAM) can be used to control the transport in organic field-effect transistors. The SAM creates a dipole moment induced electric field that is able to change the major transport type in organic materials.
In the case of fluoroalkyl SAMs, their strong dipole moment induces electric fields up to 109 V/m. These fields are strong enough to affect the underlying organic material up to a distance of 10-20 Å from the SAM. Due to the orientation of the dipole moments this leads to a hole dominated transport.
Amine-based SAMs, on the other hand, enhance the electron transport as their dipole moment is counter-directional to the one from fluoroalkyl SAMs. Due to their lower absolute dipole moment, their effect is not as strong as for fluoroalkyl SAMs.
Finally, we exemplarily show for pentacene how the SAM molecules connect to the organic material. The resulting distance of the SAM layer to the organic material determines the maximum strength of the dipole moment induced electric field.