Dear all.

I have a little problem.
I am using a negative pr to make a dot pattern.
However, after removing pr process using RR4(Dimethyl Sulfoxide) and acetone, I
can still see remained pr within 100nm size on a wafer and around dot patterns.
I tried to remove the pr using extra NMP cleaning step, but still I can see the
pr.
Would you recommend how can I remove all of the pr within 100nm size and how can
I make a perfect si wafer after cleaning step? It is very important for me
because this process wafer will be moved to MBE chamber without any defect
including remained pr or particles around dot patterns.
Thank you for your attention.

Best regards,
Gunwoo Kim