Crystal Characterization of Spherical Silicon Solar Cell by X-ray Diffraction

Abstract

We have investigated the crystal quality of spherical Si solar cells by X-ray diffraction. A Si sphere with a diameter of 1 mm was fabricated by a dropping method. X-ray pole figure measurements confirmed that the Si sphere includes twin crystals. The spherical Si solar cells were fabricated using Si spheres. The spherical Si solar cells consisting of almost the same number of crystal grains exhibited various performance characteristics, because no clear correlation between the X-ray pole figure measurements indicating the grain number and the solar cell performance characteristics was confirmed. An X-ray rocking curve and a Dash etching method for the spherical Si solar cells indicated that the short-circuit current density and open-circuit voltage of the solar cells depend on the crystallinity of intragrains.