Manufacturing method of silicon for n-type solar cell and phosphorus-added silicon

摘要

It is an object of the present invention to provide aluminum-containing silicon for n-type solar cells. It further provides a method of producing phosphorous-doped silicon refined form aluminum-containing silicone from an economical point of view. It provides silicon for n-type solar cells containing aluminum at a mass concentration of from 0.001 to 1.0 ppm and phosphorous at a mass concentration of from 0.0011 to 1.1 ppm, and having a mass concentration ratio of phosphorous to aluminum of 1.1 or greater. It further provides a method of producing phosphorous-doped silicon, including: preparing a melted mixture containing aluminum, phosphorous, and silicon, by heating and melting aluminum-containing silicon to obtain a melted product and adding phosphorous to the obtained melted product, or by adding phosphorous to aluminum-containing silicon to obtain a mixture and heating and melting the obtained mixture; and then solidifying the melted mixture in a mold under a temperature gradient in one direction.