METHOD AND APPARATUS FOR RECOVERY OF WATER AND SLURRY ABRASIVES USED FOR CHEMICAL AND MECHANICAL PLANARIZATION

摘要

Abrasive components and water are recovered from an aqueous chemical mechanical slurry used for planarization of semiconductor materials. The slurry effluent is preferably brought to a neutral pH, and cooled to a temperature between about 0 ~C and about 15 ~C. An electrical potential can be applied to the slurry effluent to facilitate agglomeration and separation of particles of abrasive material in the slurry effluent. In one embodiment, the slurry effluent is introduced into a process chamber at ambient temperature and pressure, and supernatant liquid separated from the process chamber is then subjected to a reduction of pressure in a vacuum chamber to cause gas entrapped in the supernatant liquid to bubble to the surface of the supernatant liquid for further separation and collection of water and abrasive particles from the slurry effluent. In another embodiment, slurry effluent is filtered through one or more self-cleaning reversible gross particle filter assemblies.