new process by using 3 % NaOH

Mr Liangliang Li lll2002 at
Thu Sep 8 10:45:19 PDT 2005

Dear Sir/Madam:
   How are you?
   I want to use 3% NaOH solution to strip the resist off from an 8-inch
substrate, I hope I can get your permission. the following is the detailed
process I want to do on the wet bench general:

   1: I will get my own 3% NaOH solution and transfer it into the cleaning room
to the wet bench. I will mix NaOH powder with water or dilute 50% NaOH solution
outside of the cleanining room, to get 3% solution.
   2: I will get a large beaker (9 or 10 inch round size and 6-8 inch tall) and
bring it into the cleaning room.
   3: one 8-inch Printed circuit board substrate with a mask (made of negative
resist) on the top surface will be shipped from Intel. In our own lab, my
magnetic material will be deposited to cover the whole substrate. And then, I
will bring the substrate to the wet bench.
   4: in the wet bench general, I will soak the 8-inch substrate into the 3%
NaOH solution inside the big beaker and heat to 45 degree C for 30 mins. The
resist will be stripped off from the substate.
   5: After stripping, I will clean the wet bench and waste accordding to the
manual, the 8-inch substate will be taked out of the cleaning room immediately
and shipped back to Intel.

   In our own lab, I have tested the stability of the substate in 3% NaOH
solution at 45 C. It is really stable. The hot plate size is 8 inch by 8 inch
and the tank is 11-12 inch size. So we have enough space.

   Dear Sir/Madam, if you think this process is ok in the wet bench general,
please let me know.
   Thank you very much

best regards
liangliang li

More information about the specmat mailing list