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26th European Photovoltaic Solar Energy Conference and Exhibition; 2947-2950, For monolithic thin film CIGSSe modules we performed all three patterning steps, namely for the molybdenum back electrode, the absorber layer and the ZnO front electrode (P1, P2 and P3 respectively) by picosecond laser processing. In the R&D pilot line we thus achieved a new record efficiency for an all-laser-patterned CIGSSe solar module: 14.7% as best value for the aperture area efficiency of a 30 x 30 cm² sized CIGSSe module based on the AVANCIS SEL-RTP process (stacked elemental layer – rapid thermal processing) was achieved. Optimization of the patterning processes was based on trench analysis e.g. confocal and light optical microscope, stylus profiler measurements, test structure analysis and IR characterization techniques.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 3458-3462, We report on the optimization of the picosecond laser ablation for the selective structuring of CIS (Cu(In,Ga)(S,Se)2 ) thin film solar cells to perform a monolithic serial interconnection. We introduce a relative value for the efficiency of the laser processes, the energy per ablated volume. In that respect we are examining the energy per ablated volume for induced laser ablation processes, modifications of the beam profile (elliptical and flat top beam shaping) and the application of different laser wavelengths (1064 nm and 532 nm). We show that induced laser processes (often referred as “lift-off”) are decreasing the necessary energy per ablated volume dramatically by approximately one order of magnitude. Modifications of the beam profile such as elliptical and flat top beam shaping are lowering the energy per ablated volume relative to a circular beam. The application of laser light at 532 nm decreases the energy per ablated volume compared to 1064 nm. We demonstrate that with a picosecond laser power of only 2 W the molybdenum back contact (P1 back side) and the ZnO front contact (P3 ZnO on CIS) can be structured with a speed of up to 4 m/s. A ~2 µm thick CIS layer is structured by standard direct laser ablation at higher energy densities with 200 mm/s.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3066-3071, The production of CIS (Cu(In,Ga)(S,Se)2 ) thin film solar cells is still employing some mechanical steps of structuring, where thin layers with a thickness of approximately 1 μm are selectively separated by so called pattern 1, 2 and 3 (P1, P2 and P3) for the monolithic serial interconnection. In this paper we report on selective structuring by direct and indirect induced picosecond laser ablation, both non thermodynamic ablation methods occurring at lower applied fluences than needed for heating melting and evaporation. We demonstrate that the Mo back electrode layer can be structured with a P1 process speed of more than 4000 mm/s without detectable residues and damages by direct induced laser ablation exhibiting a nonthermodynamic nature. The ZnO front electrode film can be line separated with P3 speeds up to several 1000 mm/s by indirect induced laser ablation, also a non thermodynamic process. The CIS absorber layer is structured by standard direct laser ablation at higher energy densities up to 200 mm/s indicating thermodynamic behavior. The validation of the processes P1 and P2 for the functionality within a CIS solar cell; as well as the first validation results for the P3 process will be presented. Our results indicate that ps-laser ablation processes are compatible to the module manufacturing process, reduction of pattern area by application of ps laser processing should increase the overall CIS solar module efficiency.

A clinical experience of tuberculosis (TB) in 104 pediatric patients observed at the Hospital Regional de Valdivia (southern Chile), along a sixteen year period (1986 - 2001) is presented. Pulmonary TB was diagnosed in 88 cases, extrapulmonary TB in 19 cases and both localizations in three cases. Pulmonary TB was bacteriologically confirmed in 62.5% of cases, through either gastric aspirate or sputum samples. Gastric aspirate yielded 42.8% of positive cultures; two infants who presented central nervous system involvement, died. A case of congenital TB was observed in a 30 day old infant. There were no cases of AIDS in this experience. Pediatric TB has progressively decreased its incidence in our region, particularly the extrapulmonary localization, but still represents a challenging disease to clinicians