Author(s)

Joseph Edward O’Connor, Sherif Michael

Department of Electrical and Computer Engineering/Space Systems Academic Group, Naval Postgraduate School, Monterey, USA.

The record efficiency for a thin-film, single-junction solar cell has remained static at 28.8% since 2012. This research presents a unique design that demonstrates potential to exceed record efficiency and approach the theoretical efficiency limit of ~33.5%. The findings of this study are significant, from an efficiency standpoint, and also because the cell design can be realized using existing fabrication methods that do not require complex, post-processing steps. In this study, a benchmark simulation is developed that closely resembles a high-efficiency, front-and-back contact cell. Intrinsic performance limiters are overcome by moving the emitter and front-contact to the back of the cell to eliminate electrical grid shading and improve optical performance. To further improve performance, the P-N junction formed by the emitter layer is removed from the model to allow selective Ohmic contacts to accept (reject) minority (majority) carriers as required. The design modifications improve open-circuit voltage, short-circuit current, and fill-factor which collectively boost efficiency above 30%-primarily due to a 2% gain of incident irradiance and improved optical performance.

Solar Cell, Back-Contacts, Gallium-Arsenide, Thin-Film

O’Connor, J. and Michael, S. (2016) A Novel Thin-Film, Single-Junction Solar Cell Design¹ to Achieve Power Conversion Efficiency above 30 Percent. Materials Sciences and Applications, 7, 823-835. doi: 10.4236/msa.2016.712063.