NOVELTY - The waste water (11) is stored in a tank (10) with which semiconductor waste (12) is mixed. The metal ion (13) adhering to semiconductor waste is separated from the waste by mixing substance showing acidity to the waste water. The semiconductor waste from which metal ion is separated is picked out and melted to form silicon ingot. The silicon ingot is recycled as solar cell or semiconductor wafer after removing oxygen contained by melting semiconductor waste.    USE - For manufacturing silicon ingot used in semiconductor device and solar cell.    ADVANTAGE - The silicon ingot with high purity can be obtained and semiconductor waste can be recycled easily as a solar cell or semiconductor wafer.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) crystal waste generation method involves preparing crystal waste comprising silicon and making solution to contact metal currently mixed with the waste for ionizing the metal. The ionized metal is removed through filter hole of filter film immersed to the solution and the waste is recycled;    (2) single crystal plate shaped object manufacturing method involves preparing crystal waste comprising silicon and making solution to contact metal currently mixed with the waste for ionizing the metal. The ionized metal is removed through filter hole of filter film immersed to the solution. The crystal waste is recycled and made into plate-shaped ingot; and    (3) solar cell or semiconductor device manufacturing method involves collecting processing waste generated at the time of machining. The metal mixed in the processing waste is ionized with a chemical solution and removed through filter hole of filter film immersed to the solution. The processing waste is recycled and made into plate-shaped ingot. The semiconductor processing of plate-shape object is carried out.    DESCRIPTION OF DRAWING(S) - The figure illustrates the manufacturing method of silicon ingot. (Drawing includes non-English language text)    Tank (10)    Waste water (11)    Semiconductor waste (12)    Metal ion (13)