| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for recycling sludge containing silicon, formed at the production process of semiconductor wafer, by heating the sludge at a specific temperature to remove Al, Na and Ca, etc., in the sludge, and making the silicon remain as single substance or oxide. SOLUTION: This method for recycling is to heat the sludge containing silicon at the temperature within the range of ca. 700-1300 deg.C. The heated sludge is mixed with potter's clay to mold and baked to recycle. In another example, the sludge is dried; the heated sludge is mixed with potter's clay to mold into a specified shape, and then baked at a specified temperature to recycle. Recycled products to recycle are tableware, decoration, containers, building material, and paving stone. That is to reclaim silicon in the sludge by removing and evaporating SiO2 , SiC, Al2 O3 , C, Na, Ca, etc., from the sludge, which come from a cutter, a sustaining stand, abrasive grains and washing liquid, etc., by production of semiconductor wafer from an ingot of silicon single crystal. |
