Microstructures and Optical Properties of Silicon Spheres for Solar Cells

Abstract

Silicon (Si) spheres were prepared by a powder melting method, and their microstructures and optical properties were investigated. The lattice constant of the Si spheres increased upon phosphorus (P) diffusion, compared to that before P diffusion. This was attributed to the presence of interstitial P atoms. A fluorine-doped tin oxide (SnO_x:F_y) anti-reflection film was then coated on the surface of the Si spheres. Changes in the lattice constant and bandgap of the SnO_x:F_y film occurred upon subsequent annealing. This was attributed to changes in the composition of the SnO_x:F_y film.