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Acidhood/Acidhood2 - Procedures and Rules
- Engage the acidhood in CORAL
- Understand and follow the MTL
color coding scheme
- Black & Brown (Diffusion-
RCA Station)
- Green (Standard non-metal CMOS
processing)
- Blue (Standard CMOS compatible
metal processing)
- Red (Au contaminated processing,
metals and non-metals)
- Yellow (KOH/TMAH processing
ONLY)
- Purple, and labeled SU-8 only
(SU-8 photo processing ONLY)
- Labware locations:
- Etch-room
- SU-8/gold photo room
- Photo room
- Other wet benches
- Read and follow these TRL Rules & Protocols:
- PPE is to be worn at all times
when you are working directly within the scope of acidhood,
acidhood2, or the acid pass-through. This includes Using the
chemical cart.
- PPE is to be removed anytime
you are not working directly within the scope of Acidhood,
Acidhood2, the acid pass-through and the acid cart.
- PPE gowning order is as follows:
- Apron
- Arm Shields
- Face Shield
- Acid Gloves
- Always maintain strict separation
between Au (Red) and Si (Green) labware, wafers, pieces, carriers,
tweezers, vacuum wands, work spaces….etc.
- Acidhood2 is for green and
blue dot processing ONLY.
- The Acidhood dumprinse is for
green and blue dot ONLY.
- Follow the proper procedures
when performing a post KOH/TMAH cleaning.
- Never allow a fabwipe inside
any wet station, at anytime, for any reason.
- Anytime a chemical is to be
left in a wet station unattended it’s container must
be labeled with your name, the name of the chemical(s) contained,
your phone extension, the date, and the approximate time you
will be back to attend the chemical(s).
- Never leave any solution, in
any container, in any wet station without proper labeling……EVER.
- Use opened bottles of acid
first.
- When you use the last bottle
of a chemical, always call the chemical cell phone, and make
the person responsible for chemical stock aware of this, so
that empty bottles can be removed, and fresh chemical can be
added.
- Always use the chemical cart
to transport acids and corrosives.
- Never store any chemical on
the chemical cart.
- Never leave the chemical cart
in any aisle.
- Always return the chemical
cart to the pass-through area.
- Rinse your labware properly,
and return it to its proper place of storage as soon as you
are though Using it.
- Always return tweezers and
scribes back to their appropriate place of storage.
- Thoroughly clean the acidhood
deck and utility sink when you are done.
- Thoroughly rinse off your acid
gloves before returning them to the rack.
- Always store your wafers properly.
- Always return your notebook
to the notebook rack.
- Review the standard recipes,
and use them whenever possible.
- Quartz labware is used for non-HF
chemistries, those chemistries that require the use of a hotplate,
and any chemistry that is heat producing (Piranha).
- Always be aware of the nearest
safety shower & eyewash.
- Always use the proper staging
area, and always follow protocol.
- The hazards of HF:
- Hydrofluoric
acid is a solution of hydrogen fluoride in water. It is
corrosive, and highly poisonous. Skin contact with concentrated
hydrofluoric acid or inhalation of its vapor has caused
many serious injuries, even death. Concentrated solutions
of hydrofluoric acid pass quickly through the skin and
cause deep, painful burns. Dilute solutions also penetrate
the skin, but it does not give the immediate burning sensation
caused by the concentrated form of the acid, a user may
tend to be less aware of the contact with the acid.
- Concentrated
hydrofluoric acid in contact with the skin will penetrate
the skin to damage deeper tissues. This can lead to full-thickness
skin burns. As well as this, fluoride entering the bloodstream
will trap calcium and magnesium ions with rapid harmful
effects on the heart, muscles and nervous system. Because
of this, skin absorption is the main route of exposure
for fatalities. Even dilute solutions will penetrate the
skin although the effect is usually delayed. Once the dilute
solution has penetrated, its destructive action will continue
even after surface solution has been washed off.
- Always be certain the HF Gel
is available. If it isn’t notify someone ASAP.
- Obtain the correct labware for
your process.
- Transfer your wafers, or pieces
at the correct staging area.
- Review step 4a and 4b concerning
lab protocol on PPE
- Review the PPE gowning procedure,
and gown up.
- Obtain the correct beakers/containers
for your process.
- Setup the beakers/containers
in the acidhood.
- Obtain the required chemicals
for your process from the acid pass-through.
- Never open any bottle of acid
or corrosive on the chemical cart, or outside of the acidhood.
Always inside the acidhood.
- Always add acid to water, and
sulfuric acid is to be added to hydrogen peroxide.
- Place the chemical bottle inside
the acidhood, and open it.
- If you are Using a graduated
cylinder, carefully pour a little bit more than you actually
need into a suitably sized beaker, and from this beaker pour
the chemical into the graduated cylinder, measuring the correct
amount required.
- NEVER pour a chemical
directly from the gallon bottle into a tall, narrow graduated
cylinder.
- Slowly and with care, pour the
chemical accordingly.
- Recap the bottle inside the acidhood.
- Place the chemical bottle back
on the chemical cart.
- Repeat as necessary.
- Return the chemicals to the acid
pass-through.
- Process your wafers/pieces.
- When processing is complete move
the wafers/pieces to the rinse container or dumprinse.
- Aspirate all of the chemicals
Using the correct aspirator.
- Fill and aspirate each container
three times.
- Rinse all of the labware thoroughly.
- Rinse the sink deck thoroughly.
- Rinse your acid gloves accordingly.
- Remove your PPE:
- Acid Gloves
- Face Shield
- Arm Shields
- Apron
- Move your wafers to the correct
SRD.
- Replace labware, tweezers, etc … to
their correct storage location.
- Disengage CORAL
