Modeling charge transport in organic semiconductors and simulation of organic resistive memories

This PhD work has been performed as a part of the HYMEC project within the FP7-NMP Work Programme (project number 263073). The objectives of the project (now concluded) was to resolve fundamental issues of materials science and to realize new hybrid inorganic/organic non-volatile memory devices. Specifically, we performed research towards understanding and controlling all relevant properties of systems comprising inorganic metal nanoparticles embedded in matrices of conjugated organic materials, and we demonstrated the function of such materials as non-volatile memory elements. Using the model of charge injection and transport developed in this work, we were able to model and simulate two kinds of memory devices. In Chapter 7 we will study memory elements based on charge trapping; nanoparticles can in fact act as trapping sites where charges can be trapped and de-trapped controlling the applied voltage, thus switching the device. In Chapter 8 we will study memory elements based of filaments, i. e. devices where the formation of highly conductive and localized pathways controls the conductivity of the device.