Abrégé

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.

Classes IPC  ?

• B04B 3/04 - Centrifugeurs à tambours rotatifs dans lesquels les particules ou les corps solides sont séparés par la force centrifuge et simultanément par tamisage ou filtration évacuant du tambour les particules solides par une vis transporteuse coaxiale à l'axe du tambour et tournant par rapport au tambour

Abrégé

There are provided a method for collecting silicon powder from slurry generated during a back lapping process by using a centrifuge, and the centrifuge therefor. The method for collecting silicon powder from slurry generated in a back lapping process by using a centrifuge with a bowl and a screw shaft being both installed horizontally, comprises: a collection step S1 of collecting silicon powder on inner surface of the bowl of the centrifuge in which the slurry is supplied while stopping the screw shaft and rotating the bowl at high speed so that the silicon powder and fluid are separated from the slurry, the separated silicon powder is collected on inner surface of the bowl and the fluid is discharged to a fluid outlet for a time predetermined to collect the silicon powder on inner surface of the bowl; and a discharge step S2 of discharging the silicon powder collected on inner surface of the bowl in which supply of the slurry stops, the bowl rotates at reduced speed to maintain the collected silicon powder on inner surface of the bowl, and the screw shaft which stops in the collection step S1 rotates to discharge the silicon powder collected on inner surface of the bowl for a time predetermined to discharge the silicon powder collected on inner surface of the bowl in the collection step S1.

Classes IPC  ?

• B04B 3/04 - Centrifugeurs à tambours rotatifs dans lesquels les particules ou les corps solides sont séparés par la force centrifuge et simultanément par tamisage ou filtration évacuant du tambour les particules solides par une vis transporteuse coaxiale à l'axe du tambour et tournant par rapport au tambour

Abrégé

There are provided a method and a system for regenerating a waste slurry which is disused after a slurry has been used to raise the cutting efficiency in a process of fabricating various wafers, such as semiconductor wafers, solar wafers and others. The method for regenerating the waste slurry made during various wafer fabrication processes comprises: a waste slurry mixing step (S10) of mixing a waste slurry, to disperse abrasives and chips contained in the waste slurry; a dispersing step (S20) of dispersing the waste slurry mixed in the mixing step, by using ultrasonic waves; a centrifuging step (S30) of extracting abrasive solids from the waste slurry dispersed in the dispersing step, by using a centrifuge; an abrasive solid mixing step (S40) of mixing the abrasive solids extracted in the centrifuging step; an abrasive purifying step (S50) of purifying the abrasives mixed in the mixing step, by using an abrasive purifier; a drying step (S60) of removing moisture of the abrasive solids purified in the abrasive purifying step; and a regenerating step (S70) of processing the abrasives dried in the drying step, to be in a powder state. The system for regenerating a waste slurry made during various wafer fabrication processes comprises: a waste slurry mixer (10) for mixing a waste slurry being put into the mixer (10), to scatter a precipitate composed of abrasives and chips included in the waste slurry; a particle disperser (20) for dispersing the mixed waste slurry flowing from the mixer (10), by using ultrasonic waves; a centrifuge (30) for centrifuging the waste slurry dispersed by the particle disperser (20), to extract the abrasives; a number of sub-tanks (40) for storing the abrasives extracted by the centrifuge (30); a number of mixers (50) for mixing the abrasives of the sub-tanks (40); a number of abrasive purifiers (60), each including a cleaning device installed in the centrifuge, for removing impurities remaining on the abrasives by receiving the abrasives supplied from the mixers (50); a drier (70) for drying the abrasives purified by the abrasive purifiers (60); and an abrasive powder maker (80) for regenerating the abrasives dried by the drier (70).

Classes IPC  ?

• H01L 21/02 - Fabrication ou traitement des dispositifs à semi-conducteurs ou de leurs parties constitutives