During SiO2 slurry polishing of sapphire wafers, KOH is introduced to raise
the pH.  The machines used for this process are aluminum.  If the KOH etches
the aluminum, I'm wondering if the free aluminum will have an effect on the
formation of silicates etc.  In other words, will the silicates formed from
the aluminum oxide and silicon dioxide be affected by this aluminum?  If so,
they wouldn't be able to polish very well I'd imagine!
Any comments/suggestions are greaty appreciated......Cheers