The first solar cells using in-situ doped polysilicon contacts to form both emitter and back surface field (BSF) regions are reported. The use of polysilicon contacts permits extremely low thermal budget processing (maximum 850°C 5 sec for dopant activation), preserving substrate properties. The effectiveness of the BSF is best seen with backside illumination, where the photocurrent under natural sunlight is found to be over 30% of that obtained with frontside illumination, even though the substrate thickness is comparable to the minority carrier diffusion length. The applicability of the structure to bifacial operation is considered.

back surface field, LPCVD, photovoltaic, polysilicon, polysilicon emitter, silicon, solar cell
Photonics North 2010
Department of Electronics

Du, J. (Jiang), Berndt, L.P. (Lyall P.), & Tarr, N.G. (2010). Silicon solar cells with polysilicon emitters and back surface fields. Presented at the Photonics North 2010. doi:10.1117/12.871608