Work

For my diploma in Physics I worked for one year in the department of surface chemistry and catalysis (University of Ulm). My investigations were aimed at studying the initial processes of layer growth in Si-epitaxy. I prepared clean Si-surfaces and exposed them to small amounts of gaseous SiH2Cl2. This gas decomposes on the Si-surface and leaves back Si and, depending on temperature, H and Cl. I used Scanning Tunneling Microscopy in order to investigate how the first few atoms will stick on the surface, how they form larger islands, and eventually whole layers.

After my study I signed up for some 50% jobs to finance my job serarch. The first of these was in the department of Microwave Technology at the University. My job was to accompany a lecture and visualize mathematical phenomena with little movies. The second of these jobs turned me around to solar energy. Between April and August 1997 I walked the roofs of Ulm, installing some 60 or 70 kW of photovoltaic power.

Finally I was lucky to find a nice PhD position at the Swiss Federal Institue of Technology in Zurich (ETH). My work there dealt with photovoltaic solar energy conversion. I prepared solar cells in a special configuration and studied their electrical properties. Here you can find more information on the thesis and also some pictures of the defence party.

After finishing my PhD thesis I stayed another year at ETH and followed up some ideas that emerged during writing up my thesis.

After that I went for a PostDoc position to the Swiss Federal Laboratories for Materials Testing and Research (EMPA). I investiagted reactive plasma deposition processes for hard coatings based on TiN. This material is a widely used hard coating material and, because of its nice golden colour, also often applied as decorative faux gold on all sorts of appliances. I investigated how the properties of TiN can be improved by the addition of silicon nitride, because this makes TiN harder and more oxidation resistant.

Having spent two years in hard coatings I felt it was time to return to renewable energies. It turned out to be a decision which kept me busy for some months. It started by leaving behind the compound semiconductors and moving into thin film silicon at the research centre in Jülich. My task was related to the development of light scattering ZnO front contacts. The next step happened after a relatively short time and brought me to the university of Neuchâtel. My work here is within a European Union Project and is devoted to the development of flexible solar cells. The idea is to transfer process steps that have been developed on glass to flexible PET substrates. There are all sorts of problems, like a more difficult handling, limitated process temperatures, outgassing in the vacuum vessels, curling due to stress in the films and whatever unforseeable thing that is going to happen tomorrow or the day after...

Update 2009:
Finally there were not too many unforseeable things in the project. Changes did take place, but they came form an completely different angle; end of 2008 the Swiss Confederation (or whoever) decided that the PV-Lab should be incorporated into one of the two Federeal Universities. So, now I am affilitated to the Ecole Polytechnique Federale de Lausanne.


Home Back