19.4 Efficient Bifacial Solar Cell with Spin-on Boron Diffusion

Up to date most spin-on diffusion sources based on wet chemical created boron-silicate glass (BSG) lead to a strongly degraded carrier lifetime after diffusion. In this study the implication of a spin-on boron diffusion source is applied to the fabrication of large area n-type CZ bifacial solar cell and the performance of the spin-on source is compared to a BBr3 boron diffusion concerning the resulting lifetime and emitter saturation current J0e. Comparable J0e values and a comparable lifetime have been achieved resulting in a top efficiency of 19.38% in comparison to a top efficiency of 19.60% achieved by BBr3 diffusion.