By Kevin Reddig, Team Leader, Fraunhofer IPA
“Handle with care” – this world-renowned warning sign is inherently printed on every wafer until it is safely wrapped into a finished module – and for good reason. Despite the declining price of silicon and the improved manufacturing methods, the raw wafer still has a major share in the overall cost of a module. If we assume an average wafer price of €2.70 for a 156mm multicrystalline wafer, the finished cell will cost about €4.00. Adding in the module manufacturing costs, a cell in a typical module will cost €5.00. Hence, the wafer accounts for more than 50% of the total manufacturing costs, and as such is key to optimizing the costs in the solar value chain for crystalline photovoltaic products. This paper offers some guidelines on the wet wafer separation process that are intended to aid in minimizing the cost associated with wafer breakage.
