Optimized back Reflectors for Rear Diffused c-Si Solar Cells

At present, research in c-Si solar cells is focused on increasing the efficiency while reducing the amount of used materials. Since silicon wafer and metal contribute up to 50% to the cost of a module, it is crucial to reduce the amount of these materials to fabricate cost-effective modules. In particular, for reducing the consumption of metal, the rear back contact can be patterned leaving ample metal-free regions that are well passivated. This is the concept of open-rear-metallization, typically found in solar cell concepts such as n-Pasha. In this contribution we compare a Distributed Bragg Reflector (DBR), white paint and white foil as cost-effective back reflectors for rear diffused c-Si solar cells.