Method of supplying slurry and a slurry supply apparatus having a mixing unit at a point of use

摘要

A computer-controlled slurry supplying apparatus for providing abrasive slurry to a chemical mechanical polishing (CMP) machine in a semiconductor manufacturing process preferably comprises a storage portion for accepting and storing a quantity of undiluted slurry, a mixing portion for accepting undiluted slurry from the storage portion and mixing with a diluting solution to created a diluted slurry, a supply portion for holding the diluted slurry, and at least one point-of-use mixing unit for mixing at least one chemical additive to the diluted slurry at or near a dispensing nozzle at the point of application. Each of the above portions of the slurry supplying apparatus further includes a re-circulation means for keep solutions in a mixed and agitated state. A method for using the slurry supplying apparatus comprises steps of controllably operating various valves, pumps, and sensors to maintain a desired slurry composition and flow rate.