Abstract: A method to dice polycrystalline silicon into solar cell wafer by following grain growth direction of crystal so to allow larger grains to present on a surface of the solar cell wafer to reduce the grain number per unit area on the surface of the solar cell wafer and/or photo transfer interface; i.e., to reduce potential barrier and resistance created among grains; whereas extra foreign matters in the boundary will compromise photo transfer efficiency and electronic migration capability of the substrate surrounding the boundary, reduced number of boundary in turn upgrade photo transfer efficiency.