Dresden 2009 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
DS: Fachverband Dünne Schichten
DS 21: Organic Thin Films I
DS 21.6: Talk
Wednesday, March 25, 2009, 10:45–11:00, GER 38
Optimisation of the insulator/organic interface for DIP/sapphire OFETs — •Sönke Sachs1, Matthias Bräuninger1, Achim Schöll1, and Eberhard Umbach1,2 — 1Universität Würzburg, Experimentelle Physik II, Am Hubland, 97074 Würzburg — 2Forschungszentrum Karlsruhe, Weberstraße 5, 76021 Karlsruhe
The quality of the insulator/organic interface, where the charge carrier channel is located in organic field-effect transistors (OFETs), decisively determines the performance, particularly the charge carrier mobility of the devices. A high structural order of the organic film, as well as a small number of defects like grain boundaries are desirable. To optimise the insulator/organic interface diindenoperylene (DIP) microcrystallites were grown by organic molecular beam deposition (OMBD) on highly ordered, atomically flat, and clean sapphire single crystals. The properties of the surface and of the deposited organic films were analysed in situ by means of analytical tools such as LEED, XPS, and NEXAFS, as well as by AFM. The parameters for the OMBD deposition as well as for the substrate preparation were systematically optimised in order to increase the crystalline domain sizes in the organic film. After contacting, first measurements of the charge carrier mobility were performed in order to correlate the device characteristics with the film properties.