Regensburg 2010 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 27: Poster: Organic Electronics and Photovoltaics

CPP 27.11: Poster

Wednesday, March 24, 2010, 17:30–19:00, Poster C

Mobility Measurements of aza-BODIPY for Organic Solar Cells — •Moritz Hein, Roland Gresser, Torben Menke, Karl Leo, and Moritz Riede — Inst. f. Angewandte Photophysik, Dresden, Deutschland

For organic electronics applications, e.g. organic solar cells, new appropriate materials, in particular with high charge carrier mobilities are crucial. This contribution focuses on the promising absorber material class of aza-BODIPY. A series of this new donor material, with four different substituents and increased molecular rigidity has been analyzed in respect of mobility. Depending on the electron donor strength of the substituents, the HOMO (highest occupied molecular orbital) energy of the materials can be tuned from 5.1 eV to 5.7 eV. Structural modification, increasing the rigidity of the molecule and extending the planar pi-conjugated system lead to a better molecular orbital overlap of two adjacent molecules in the crystal structure. We investigate the influence of this structure variation on the mobility. Two different methods are used: field effect transistor (OFET) and space charge limited current (SCLC) measurements. A comparison of the mobilities of the different materials and techniques is presented. Furthermore, the film morphology has a huge influence on the mobility. To study this, the effect of heating the substrate during evaporation is used.