Hello All,

Thank you all very much for the replies I got for my previous queries. I
have another one now ;-)

I am trying to clean fused quartz wafers that have been used as substrates
several times for coating photoresist (Shipley S-1800 series). I have tried
solvent clean (Acetone & Methanol) and even Piranha (1:1) but still I see
that the surface has some traces of photoresist on it. I would like to know
the best procedure for removing organic and metallic contaminants (Cr,Al)
from fused quartz wafers without affecting the wafer itself. Please let me
know if you have any suggestions.

Thanks,
Sreemanth