Regardless of whether the silicon is purified in the Czochralski process, in a direct casting process for multicrystalline silicon or in special ribbon growth processes, polycrystalline silicon must first be melted. For optimal crystal growing, the silicon melt must be processed within narrow temperature tolerances. The required precise power control of the heating elements can be done with a power controller from POWERTECH Industrial Corporations Tesla-Family. These units can be found around the world wherever heating or melting must be done precisely and reliably and to the very highest of production standards.