Dresden 2017 – wissenschaftliches Programm
CPP 55.3: Vortrag
Donnerstag, 23. März 2017, 11:30–11:45, ZEU 222
Construction of Polycrystalline Morphologies: A Case Study for C60 and Pentacene — •Sebastian Schellhammer1,2,3, Frank Ortmann1,2, and Gianaurelio Cuniberti1,2,3 — 1Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden — 2Dresden Center for Computational Materials Science, TU Dresden — 3Center for Advancing Electronics Dresden, TU Dresden
Based on the processing conditions, the morphology of small-molecule organic semiconducting materials can be varied from highly ordered single crystals to polycrystalline and amorphous. Also grain shapes vary from spherical, platelets, or rod-like. Differences in the morphology affect the energy landscape and, thus, the macroscopic charge transport behavior of the film. We present a nucleation-equilibration approach for the construction of morphologies with gradually varying degree of structural ordering. Based on geometrical considerations, the computational requirements are low enabling the construction of systems of experimentally relevant sizes. Application is demonstrated for C60 and pentacene structures varying from almost amorphous to highly ordered phases. We will also discuss the impact of morphologies on charge transport.