Optimization of the Light Trapping Nano Structures in CdTe Thin Film Solar Cells

The optical absorption and the short circuit current of CdTe thin film solar cells have been improved by incorporating arrays of nanostructures in the gold back contact/reflector layer. In this study, three different nano pillar heights, 100, 200 nm, and 300 nm with two periodicities, were investigated. ANSYS HFSS wave optics simulation software was utilized. An increase of 10% in short circuit current density is achieved comparing to the planar cell of an equivalent thickness. Further enhanced performance of CdTe solar cells is expected by incorporating such optimized nanostructure arrays of different sizes and shapes.