NOVELTY - The silicon raw materials are fed to crucible. The solid silicon raw materials are melt into liquid silicon. The crystallization region slot is communicated to the crucible drain mouth and slot is filled up with liquid tin metal or other alloys as carriers. When liquid silicon shifts to the end of the molding region, liquid silicon is solidified to solid state. The buffer arranged at the top of corresponding silicon surface in the crystallization region, is used to regulate thickness of silicon wafers. Thus, float method for producing silicon wafers is carried out.    USE - Float method for producing silicon wafers for semiconductor, and solar cell.    DETAILED DESCRIPTION - The silicon raw materials are fed to the crucible through a feeding unit and the temperature inside the crucible is set above the melting point (1421 degrees C) of silicon. The solid silicon raw materials are melt into liquid silicon, when the temperature is above 1421 degrees C and argon gases or other inert gases are discharged continuously through a feeding inlet over the liquid silicon. The crystallization region slot is communicated to the crucible drain mouth and the slot is filled up with liquid tin metal or other alloys as carriers whose melting point are lower than that of silicon. The temperature near the discharge port is higher than the melting point (1421 degrees C) of silicon and temperature at the other end is between 1421 degrees C and 400 degrees C. When liquid silicon shifts to the end of the float method molding region, liquid silicon is solidified to solid state. The buffer arranged at the top of corresponding silicon surface in the crystallization region, which is adjacent to the crucible drain mouth, is used to regulate the thickness of silicon wafers. The molding crystallized silicon wafer is cut into wafers in the wafer cutting region according to the requirements after being subjected to the cooling section, and burnishing and polishing portion. Thus, float method for producing silicon wafers is carried out. An INDEPENDENT CLAIM is included for apparatus adopting float method for producing silicon wafers.