Advancements in the utilization of screen-printed boron doping paste for high efficiency back-contact back-junction silicon solar cells

Screen printed boron doping paste can be used as a cost-effective and highly flexible dopant source in silicon photovoltaics. In combination with a co-diffusion approach, it can help mitigate some of the increased costs advanced solar cell concepts inherit. Aiming at the fabrication of high efficiency back-contact back-junction solar cells, we investigate the limitations of direct structured application regarding minimal feature sizes. We find minimal feature sizes of 75 and 120 μm for n
⁺⁺
- and p
⁺⁺
-doped regions, respectively. We also demonstrate a fully compatible and homogeneous (ΔR□/R□ = 3%
_rel
) co-diffusion process, creating all dopings at once.