Wolfgang Tress was born in Münsingen, Germany on August 15th, 1981.
He studied electrical engineering at Ulm university focusing on semiconductor technology and renewable energies. A stay abroad in Bologna, Italy (2005) and an experimental student thesis in the field of microsystems technology accompanied his studies. He made an internship at the Zentrum für Sonnenenergie- und Wasserstoffforschung Baden-Württemberg (2004) and in an industry research department of Bosch in Stuttgart (2006). During his studies he was scholarship holder at the German national academic foundation (Studienstiftung des deutschen Volkes). In his diploma thesis 2007 he started working on organic materials, focusing on the electrical modelling of organic solar cells. Since 2008 he is working on the same topic in his PhD thesis at the Institut für angewandte Photophysik (IAPP) at the university of Dresden.
Modelling of organic solar cells
In a renewable energy mix photovoltaics gets more and more important. Organic solar cells, still in the state of fundamental research, provide a high potential due to expected low cost production processes (role-to-role) and low material consumption. Furthermore they open a new field of application as mobile and flexible low-cost products. Current issues are the increase in efficiency and stability of these devices.
As physical processes in organic materials are not well understood, fundamental research including modelling and simulation is necessary.
The models and simulations developed in this thesis are supposed to contribute to the understanding
of the working principle of organic solar cells, to propose optimizations to the experimental physicist, and to estimate the potential of material systems.
In particular, solar cells based on small molecules are examined, which are developed at the IAPP. The work focuses on electrical simulations. As result of the calculations one obtains current-voltage characteristics, which allow a detailed analysis of the solar cell performance. Main issues are the proper choice, modification, and improvement of the models and the determination of material parameters, which are difficult to measure experimentally (like band structure, charge carrier mobilities, barriers, influence of spatial disorder etc.) Goal of the simulation tool is a description of organic multilayer solar cells, which is as realistic as possible and considers several physical effects.
The thesis is supervised by Prof. Dr. Karl Leo.
