METHOD OF RECLAIMING SILICON POWDER FROM SLURRY GENERATED DURING BACK LAPPING PROCESS

摘要

There is provided a method for reclaiming silicon powder by collecting and refining the silicon powder from slurry generated during a back lapping process, a post-process step for semiconductors, and, more particularly, a method for reclaiming silicon powder through collecting a low-purity silicon powder from slurry generated during a back lapping process by using a collecting centrifuge; mixing the collected silicon powder from the collecting centrifuge with a chemical solution to dissolve impurities; and refining the silicon powder mixed with the chemical solution into a high-purity silicon powder by using a refining centrifuge. The method for reclaiming silicon powder from slurry generated during a back lapping process comprises: a collecting step S100 of collecting silicon powder from the slurry, wherein the collecting step S100 supplies the slurry to a collecting centrifuge (100) in which a bowl and a screw shaft are installed horizontally and a bowl motor M1 and a screw shaft motor M2 are installed to individually control rotation of the bowl and screw shaft, and collects silicon powder from the slurry by a centrifugal separation method; a refining step S200 of refining the silicon powder collected from the slurry, wherein the refining step S200 comprises: a stirring step S210 of mixing the silicon powder collected in the collecting step S100 with a chemical solution having an acid as a main component and dissolving impurities; and a separating step S220 of supplying the mixture mixed in the stirring step S210 to a refining centrifuge 300 and separating the silicon powder; a drying step S300 of drying the silicon powder refined in the refining step S200 in a vacuum drier; and a packaging step S400 of packaging the silicon powder dried in the drying step S300.