Microlens Array Light Trapping in Cdte/cds Solar Cells

In light of the continued rise in fossil fuel costs, alternative energy sources, such as solar technology, are increasingly important. Concentrating photovoltaic systems are promising for future efficient and cost effective competition with fossil fuels. We employ a microlens array to a CdTe/CdS semiconducting solar cell to increase efficiency via light trapping. Since the microlens array will cause a local increase in incident light intensity, it should cause a corresponding increase in efficiency. The solar cell is deposited layer by layer. The CdS layer is chemically deposited. The CdTe layer is deposited using an additive manufacture technique of laser melting of CdTe powder. It is a novel approach to apply CdTe laser melting to a solar cell application. A CdCl2 thermal treatment is implemented following CdTe deposition to compensate for CdTe/CdS lattice mismatch. I present a novel approach to scalable microlens array manufacture. A microlens array mold is etched out of foturan glass that has been treated with femtosecond laser exposure. PDMS (polydimethylsiloxane) microlens arrays are cast from this foturan glass mold to greatly decrease manufacture costs of the microlens array. Preliminary results look promising.