Annealing, Passivation and Contacting of Ion Implanted Phosphorus Emitter Solar Cells

Adeline Lanterne (1, 2) , Samuel Gall (1, 2) , Sylvain Manuel (1, 2) , Remi Monna (1, 2) , D. Ramappa , M. Yuan , Pierrette Rivalin (3) , Aurélie Tauzin (3)

1 LITEN - Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux
2 INES - Institut National de L'Energie Solaire
3 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information

Recently, ion implantation doping technique has shown potential to improve silicon solar cell efficiency while reducing the number of process steps. In this context, we developed and studied a p-type silicon solar cells fabrication process with a phosphorus implanted emitter. The process is similar to the POCl 3 homogeneous diffusion process however replaces the high temperature gaseous diffusion and associated steps by an implantation step followed by an annealing to activate phosphorus dopants. We employed simulation results and advanced characterization to optimize the annealing temperature. The influence of this annealing temperature on the activated dopant profiles and on the crystal damage was highlighted. By adding an O 2 flow during the annealing step, a SiO 2 layer was grown and an optimum SiO 2 /SiNx stack was used to improve passivation. Its benefits were quantified by comparison with the standard SiNx passivation. The influence of the implantation dopant density on the passivation quality was also studied. By using an adapted front screen-printed silver paste to contact this new implanted emitter profile we demonstrated an 18,73% certified solar cell efficiency on industrial 156x156 mm 2 pseudo square substrate.

Keywords: solar cells; ion implantation; phosphorus; passivation; thermal annealing; screen-printing

Domains: Engineering Sciences [physics]; Engineering Sciences [physics]; Electric power; Engineering Sciences [physics]; Optics / Photonic; Engineering Sciences [physics]; Materials; Engineering Sciences [physics]; Micro and nanotechnologies/Microelectronics

Adeline Lanterne, Samuel Gall, Sylvain Manuel, Remi Monna, D. Ramappa, et al.. Annealing, Passivation and Contacting of Ion Implanted Phosphorus Emitter Solar Cells. Energy Procedia, 2012, 27, pp.580 - 585. ⟨10.1016/j.egypro.2012.07.113⟩. ⟨cea-02570730⟩