Spherical silica micro-lenses for enhanced light absorption in thin crystalline silicon solar cell

Enhancing the light absorption in ultra-thin crystalline silicon wafer based solar cell is a challenge to be met. Among several approaches and techniques to do so, the very simple yet effective technique of lensing the light into the substrate is investigated in this work. Spherical silica micro-lenses have been designed and studied. The effect of the micro-lenses has been observed for varying substrate thickness and an absorption enhancement of 65% is noted for a substrate thickness of 3μm. Also, an improvement in wide angle light trapping is observed, which can act as an efficiency enhancer for solar photovoltaic application.