Polishing is the next step in the wafer manufacturing process. Most Prime wafers go through 2-3 polishing steps using progressively finer slurry (slurry is the polishing compound). The polishing is normally done on the frontside of the wafer, but sometimes it is done on both sides. Polishing is done on huge precision machines that are capable of extraordinary tolerances. The systems at the RIGHT have 59" wheels and are made by Speedfam Inc. Prior to final polishing some wafers may receive what is called backside damage, two examples would be bead blast and brush damage. The wafers may also receive a backside coating of Polysilicon, all these treatments are done to the backsides of the wafer for the purpose of Gettering defects (later in the device manufacturing process these backside treatments will draw defects in the Silicon towards the backside of the wafer and away from the frontside where the devices are being built, this is called Gettering). After polishing the wafers are rinsed in DI water and scrubbed to remove any residual slurry compounds from the wafer.