Bayer AG / Bayer Solar is the largest commercial producer of multicrystalline silicon
wafers (Baysix) for photovoltaic applications. For fabrication of the wafers mainly the blockcasting
technology is employed. Baysix represents a material with outstanding quality
properties; several research groups already have achieved efficiencies well above 16 %. In
addition to the block-casting production facility a smaller casting unit is used for research
purposes concerning e.g. novel feedstock sources or improved processing sequences. A large
variety of characterisation techniques is used in the Bayer research labs at the Uerdingen site.
The characterisation tools are applicable to as-grown wafers (e.g. high resolution resistivity
and lifetime maps) as well as solar cells (e.g. electrical characterisation, locally resolved
measurements of all relevant solar cell parameters) and include a Bayer-own test solar cell
process as well.
In this paper we describe shortly the techniques used in the production of
multicrystallin Silicon (mc-Si) solar cells and the experimental techniques used in the solar
cell characterisation who will be used during the project.
Solar cell processes are designed for our wafers at independent research institutes
(FhG, ISE, Freiburg and UKN, Konstanz) and some results will be shown.
