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The aim of this thesis was to improve a kinetic Monte Carlo simulation of electron movement in a dielectric by including the movement of oxygen vacancies. Starting from the code implemented by G. Jegert during his PhD study, new features has been added and a few adaptions to the new point of interest were made. New defect types, tunneling assisted Poole-Frenkel effect, two interface layers and the movement of oxygen vacancies were added among various smaller changes. The final time depending simulation with a constant bias electric field dealt with the question on the influence of the conduction band offset on the spatial distribution and the types of the defects. It was shown that for a low offset the defects are mainly neutral, while a higher offset led to a higher positive charge, where the majority of the defects were charged double positive. These positive charged vacancies moved to the cathode where there was an accumulation of defects, while the bulk of the dielectric remains almost defect free. Since the charged defects inhibit the changing of the polarization of the dielectric the offset can be adjusted rather low, so that the majority of the defects is neutral. At the same time a lower offset leads to a higher leakage current, since the energetic barrier for Schottky emission is lowered.
CIS (Cu(In,Ga)(S,Se)2) thin film solar cells show a high potential to achieve the efficiencies of Si wafer-based solar cells. The commonly applied patterning processes for the integrated interconnects are based on nanosecond laser ablation and mechanical scribing. Both methods introduce damages on the thin films by thermal effects and mechanical forces. By picosecond laser processing we realized all three patterning steps to the monolithic thin films CIS modules, namely the separation of the molybdenum back electrode, the absorber and the ZnO font electrode (P1, P2 and P3 respectively). We achieved an efficiency of 14.7% for 300 x 300 mm² modules.
Diese Vorlesung entstand aus dem Wunsch der Studenten heraus, einzelne Gebiete der Physik nach dem Absolvieren des Grundkurses Quantenphysik genauer zu durchleuchten. Dabei konnten die Studenten aus einem Gebietskanon auswählen. So ist zu erklären, dass nicht nur Themen der Quantenmechanik enthalten sind, sondern auch elementare Abschnitte über Schwingungen und Wellen sowie Dipole und die elektromagnetische Masse.