Silicon nitride powder for mold releasing agent for casting polycrystalline silicon ingot, slurry containing the silicon nitride powder, mold for casting polycrystalline silicon ingot and manufacturing method thereof, and polycrystalline silicon using the mold Method of manufacturing ingot casting

摘要

Disclosed is a silicon nitride powder for a release agent of a mold for casting a polycrystalline silicon ingot which can prepare a polycrystalline silicon ingot having high photoelectric conversion efficiency at low cost. Specific surface area is 5 to 40 m²/ G, the content ratio of oxygen present in the particle surface layer is FSO (mass%), the content ratio of oxygen present inside the particle is FIO (mass%), the specific surface area is FS (m²/ FSO is 8 to 30, FS / FIO is 22 or more, and the ratio D 10 / D 90 of 10% by volume diameter D 10 and 90% by volume diameter D 90 in the particle size distribution measurement is 0 .05 to 0.20, silicon nitride powder for mold release material of mold for casting polycrystalline silicon ingot, slurry containing the silicon nitride powder, mold for casting polycrystalline silicon ingot and manufacturing method thereof, and And a method for producing a polycrystalline silicon ingot using the mold is provided.