Monocrystalline silicon is a kind of silicon crystal material with fixed crystal orientation, which is generally used as the substrate of semiconductor integrated circuit and also used to make solar cell. Polycrystalline silicon is a kind of silicon crystal material without uniform fixed crystal orientation, which is generally used for solar photovoltaic power generation, or for the raw material of monocrystalline silicon. Monocrystalline silicon is a kind of excellent high-purity semiconductor material.  The purity of IC level is required to be more than 9N (99.999999%), and even 11n (99.9999999%) for zone melting monocrystalline silicon wafer. Generally, CZ and FZ are used to form long crystals, whose orientation is determined by seed crystal. Monocrystalline silicon is the most important semiconductor material, accounting for more than 90% of the semiconductor material market, which is the basic material of information technology and integrated circuit.