Cu(In,Ga)(S,Se)_2 thin film photovoltaic cells show excellent potential for high cell efficiencies. Especially film deposition by sputtering technologies enables superior absorber film properties. Hence the availability of high quality sputtering targets which allow stable high rate deposition becomes a key requirement. We report on the latest developments of rotatable targets of pure In, CuGa, and CuInGa alloys. For all relevant target compositions special tubular fine-grain materials have been developed with the additional requirement to be operated at power densities well above 10 kW/m. We present sputter data from our thin film application center such as sputter rates, possible power densities and observed arcing levels. We also discuss the importance of a proper design of target microstructures for this alloy family to achieve stable sputter performance and, especially in the case of CIG alloys, a uniform film composition.
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