user problems at wbnonmetal
beckwith at snf.stanford.edu
Wed Jan 24 16:11:02 PST 2001
Over the past two weeks I have noticed the following user problems:
1. Buffered HF drips on the deck (how can I tell it is buffered HF? It is
those white crystals you see on the deck, and all over the two buffered HF
tanks). PLEASE clean up after yourselves! If you need instructions on this
2. At this very moment the 6:1 HF tank has clean room paper in it. Someone
left loose paper sitting on the deck. PLEASE do NOT do this on ANY wet
bench deck. The exhaust will suck the paper to the back of the bench. The
paper will either end up in one of the acid baths (as happened today), or
worse, it will get sucked into the duct work.
3. Cover the HF tanks when you are finished using them. If you drip HF
anywhere clean it up!
4. The H2SO4:H2O2 hot pot has clumps of resist floating around in it. If
you removed your wafers from this hot pot your wafers are NOT clean. I
hope you did NOT take them to wbdiff! If the sulfuric bath does not turn
clear you do not have enough H2O2 in it. Add some. Again, need help? Ask
5. The left dump rinser still does not spray. Please remove your cassette
handles and put them in the bottom of the dump rinser. Then press START.
Don't leave handles with acid on them for someone else to pick up.
6. When you use the DUMP DOOR to empty the dump rinsers make sure you
press the button again to refill the dump rinsers with DI water. I keep
finding the dump rinsers empty. Empty dump rinsers enhance the possiblity
of contamination in the dump rinser.
We all have to work here, some of us need to keep our wafers
uncontaminated, please keep the bench uncontaminated and clean.
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