Idaho Microfabrication Laboratory
CLEANROOM SAFETY TRAINING
ET105 & ET107
Peter Miranda
Director, Idaho Microfabrication Laboratory
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Idaho Microfabrication Laboratory
Agenda
General equipment information
General cleanroom safety rules
Gowning procedures
Hazardous chemicals
Hazardous gases
Hazardous chemical spill containment
IML Website
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Idaho Microfabrication Laboratory
General Cleanroom
Class 1000 clean
room
- < 1000 particles greater
than 0.5µm in size for
a given cubic foot of
air.
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Idaho Microfabrication Laboratory
Cleanroom Equipment Capabilities
 Materials Science Research
 Scanning Electron Microscopes
(SEM)
• Thermoionic
o Electron Backscatter
Defraction (EBSD)
o Energy Dispersive
Spectroscopy (EDS)
• Field Emmision – NEW!
 IC Processing
 Oxide/Diffusion Furnace
 Photolithography
• Spin coater
• Contact aligner
 Wet bench processing
 Thin Film Deposition
 PVD
• Thermal Evaporator
• Magnetron Sputter - 2 tools
 Thin Film metrology
 Ellipsometer
 Nanospec
 Four point probe
 Optical profilometer
 Dry Etch
 Bosch etcher - DRIE
 Plasma Asher
 Ion Mill – coming soon!
 Chemical-Mechanical Polisher
 Wire Bonder
 Rapid Thermal Processor
 Various high powered
microscopes
 Single wafer cleaner
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Idaho Microfabrication Laboratory
General Cleanroom Safety Rules
 Rules and Guidelines for Personal Lab Behavior
 Drinking, eating and gum-chewing are not allowed in any part of the lab.
 Full cleanroom attire must always be worn while in the cleanroom.
 Be discrete in coughing, sneezing, or blowing your nose. At the very least, turn away
from the processing area and change your gloves before commencing processing.
 Minimize the amount of materials stored in the lab. All personal items must be labeled
with your full name, and contact phone number.
 Acceptable Materials in the Cleanroom
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Cleanroom notebooks and cleanroom paper
Wafers and tweezers (put away when not in use).
Pens (preferably ball-point).
Materials with smooth, hard surfaces which can be cleaned with alcohol wipes.
 The following materials are not considered cleanroom-compatible:
 Wood pulp-based paper products, which includes regular paper, tissues, cardboard,
books, and magazines.
 Styrofoam products.
 Any powders.
 Erasers, pencils, felt-tipped pens (other than Sharpie markers).
 Anything that can easily shred or aerosolizes; i.e., anything that may serve as a source of
particles.
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Idaho Microfabrication Laboratory
General Cleanroom Safety Rules
 Never work alone in cleanroom when working on the wet bench. Use the buddy
system.
 Unlabeled chemicals are significant environmental and health hazards. When you
make up a solution, remember to label it. When labeling a solution, you should
include the following:
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Name of the material contained
Primary hazard of the material
Person responsible for the material
Date of filling or preparation
 If your name, the substance, and a date are not present on any chemicals left out on
the counters (specifically those in glassware), the chemicals will be disposed of. If
any chemicals need to be left out on the counters for longer than 48 hours, the label
should include the date prepared and the date the solution will be cleaned up. Be
courteous and clean up you own chemicals in reasonable time frames.
 Leaving the lab
 Clean up after yourself. Leave stations neat and ready for the next person to use. Remove
personal items from general-use areas after you are done processing. Label your work.
 Any materials you plan on taking out of the lab with you should be bagged to prevent
contamination.
 In the gowning room: remove your bunnysuit from the bottom up:
•
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Booties - Put booties in the appropriate bin.
Suit - Keep the sleeves, main body, and as much of the suit as possible off the floor.
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Idaho Microfabrication Laboratory
General Cleanroom Safety Rules
 No shorts or open toed shoes
in ET105 or ET107.
 No shorts or skirts allowed in
labs.
 Know your safety exits.
 Turn off the lights if you are
the last one out.
 Report any safety concerns to
the IML director.
Exits
Fire Extinguisher
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Idaho Microfabrication Laboratory
Cleanroom Gowning Procedures
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Cleanroom bunnysuits are intended to keep the cleanroom clean, not the wearer
safe. They do provide an extra layer of protection that may protect against minor
spills and splashes, however, when using dangerous materials, a plastic or rubber
apron should be used.
Do not enter gowning room with dirty shoes ie. mud, sand, etc.
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Put on hood (all facial hair must be covered with hood, mask, etc.)
Put on bunny suit
Put on shoe covers
Put on gloves, safety glasses
•
Blue (Nitrile) gloves are used ONLY for non-chemical operations
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Yellow (Latex) gloves are to be used for all chemical operations.
o
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o
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Typical uses include working on vacuum systems, protecting substrates from contamination, operating
microscopes, operating equipment.
Because these gloves don't get contaminated with chemicals, you are permitted to operated door
handles and lab equipment with these gloves.
Latex gloves do NOT protect against all chemicals so additional gloves might need to be worn over the
latex gloves for protection.
Typical chemical operations are mixing acid solutions (except HF), using KOH, using etchants, using
organic solvents or chemicals, etc.
NEVER operate door handles or equipment while wearing yellow gloves. Residual chemicals on the
gloves can contaminate surfaces and cause serious injury to future users.
Sign-in to cleanroom logbook
Place single-use gowning gear in hamper, if you are a frequent user of the IML,
you can hang up your gear for the next time. A storage rack is located in the
clean gowning are to enable limited (10 uses, or until shoe covers show particles)8
re-use for economic reasons.
Idaho Microfabrication Laboratory
GENERAL EQUIPMENT SAFETY
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Idaho Microfabrication Laboratory
General Equipment Safety
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Dangerous Light Sources: Plasma, Ultraviolet lamps
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Thermal Evaporator
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Moving parts - pinch points
Dry Etch
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Clean up area when you are done.
Never leave unlabeled chemicals laying around.
Wear chemical apron, face shield, gloves in addition to bunnysuit.
SEM
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Smocks, gloves, face mask, eyewear.
Wipe down all working surfaces when your done working on tool.
Wet Bench Processing – Hazardous chemicals!
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UV Source on Mask Aligners, Pattern Generators
Light from an Ar plasma in sputter deposition and ion etch tools
Plasma, N2 asphyxiation
CMP
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Smock, gloves, eyewear
Moving parts – pinch points
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Idaho Microfabrication Laboratory
HAZARDOUS CHEMICALS
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Acids
Are typically soluble in water.
Are corrosive.
Form salts when mixed with bases.
Turn litmus paper red. Litmus paper located above
wet bench and inside toolbox.
Burn organic tissues and/or inorganic materials.
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Acids
 Acetic - CH3COOH
 Liquid and vapors cause severe burns to skin. Reacts vigorously with oxidizing agents and other acids
(particularly nitric). Odor similar to that of strong vinegar. Incompatible with most other acids. Store
alone!
 Chromic - H2CRO4
 Liquid and vapors cause severe burns to skin. Corrosive to nasal passages. Contains a suspected
carcinogen.
 Hydrochloric - HCL
 Highly corrosive to skin and mucous membranes. Repeated exposure causes erosion of teeth.
 Hydrofluoric - HF
 Liquid and vapors cause burns that may not be immediately painful or visible. HF attacks glass. HF
looks like water and can kill in small amounts. Found in Buffered Oxide Etch (BOE). Use only in
plastic containers.
 Nitric - HNO3
 Highly corrosive to skin, mucous membranes and teeth. Highly reactive with acetic acid. Reacts
explosively with combustible organic or other oxidizers. Use only in glass containers.
 Phosphoric - H3PO4
 Liquid is highly irritating to skin. Vapors are highly toxic. Contact with most metals causes formation
of flammable and explosive hydrogen gas.
 Sulfuric - H2SO4
 Liquid and vapors are extremely corrosive to skin and mucous membranes. Generates heat upon
contact with water. Reacts with acetic acid. Keep away from water.
 Citric - C6H8O7
 Skin and eye irritation
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Idaho Microfabrication Laboratory
Special Precaution on HF

Hydrofluoric Acid
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Hydrofluoric acid (HF) is EXTREMELY dangerous. Be extra attentive when working with HF. HF
is colorless and odorless; it looks and smells like water. HF is an ingredient in many oxide etches
which are used to etch glass. Because of the danger, only trained personnel should pour HF.
According to DuPont’s MSDS.
HF will:
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HF may:
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Kill if more than 5% of the body is exposed.
Kill if ingested or inhaled.
Depending on concentration, not cause pain for up to 24 hours after contact.
Some of the symptoms of HF exposure are:
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Penetrate skin.
Attack (decalcify) bones.
React with your body’s chemicals to make poisonous salts.
Itching.
Red or white discoloration of the skin.
Pain within 24 hours after contact.
Discoloration under fingernails or toenails.
Treatment with Calcium Gluconate Gel

Calcium gluconate gel is a topical antidote for HF skin exposure. Calcium gluconate works by
combining with HF to form insoluble calcium fluoride, thus preventing the extraction of calcium
from tissues and bones. Keep calcium gluconate gel nearby whenever you’re working with HF.
Calcium gluconate can be ordered through Life Safety Associates www.lifesafety.com. Calcium
gluconate has a limited shelf life and should be stored in a refrigerator if possible and replaced with
a fresh supply after its expiration date has passed. Use disposable gloves to apply calcium gluconate
gel. Even after applying calcium gluconate, it is essential that a medical evaluation be made.
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Acids – Waste Disposal
Acids (including piranha), must be aspirated from
their containers. An aspirator has a Teflon® tube
through which it sucks a liquid from a container. Our
Microfab wet bench has an aspirator. The fresh water
plenum flush is automatically activated when an
aspirator is turned on. The plenum flush adds water to
aspirated waste, further diluting it. NEVER POUR
ACIDS, BASES directly down a drain: Always use
the aspirator. Never mix solvents with acids when
aspirating – This is a potentially explosive
combination! And remember AAA-always add
acid to water!
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Bases
Are typically water soluble.
Are slippery.
Taste bitter.
Form salts when mixed with acids.
Turn litmus paper blue.
Are corrosive.
Burn organic tissues.
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Bases
Ammonium Hydroxide - NH4OH
 Irritating to skin and mucous membranes. Emits highly
toxic vapors when heated.
Potassium Hydroxide - KOH
Sodium Hydroxide – NaOH
Photoresist developers
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Bases – Waste Disposal
 Aspirate chemical waste same as acids.
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Solvents
 A solvent is a chemical substance which dissolves another substance. The most
common solvent is water.
 Solvents are used extensively in the electronics industry. Compounds such as
Isopropyl Alcohol (IPA) and acetone are used to clean and dry wafers, glassware,
equipment, and most working surfaces in the lab. In addition, solvents are the
principle components of many process chemicals such as photoresist.
 Organic solvents react chemically with acids, producing a violent reaction. As a byproduct of the chemical reaction, gases are released, as well as a great amount of
heat. Therefore, acids and solvents and their vapors should never come into contact
with one another.
 Organic solvents should never come in contact with oxidizers such as hydrogen
peroxide and chromic etch. Oxidizers are a class of their own and will also react
violently with organic solvents and acids.
 Major solvents and their abbreviations used in the IML:
 Acetone - ACE
 Isopropyl Alcohol - IPA
 Propylene Glycol Monomethyl Ether Acetate - PGMEA
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Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Solvents
 Acetone-ACE
 Irritates eyes, nose and throat; headaches; skin dryness
 Isopropyl Alcohol-IPA
 Dries skin; irritates eyes, nose and throat; drowsiness
 Methyl Isobutylketone-MIBK
 Irritates eyes, nose and throat; may cause weakness, dizziness,
lightheadedness, nausea, vomiting, or kidney damage.
 Propylene Glycol Monomethyl Ether Acetate-PGMEA
 Irritant; may cause itching, redness and burns to skin; ingestion may
cause diarrhea, kidney and liver damage
 Ethyl Lactate-Positive Photo Resist
 Combustible liquid; skin, eye, respiratory irritant; nervous system toxin20
Idaho Microfabrication Laboratory
Cleanroom Hazardous Chemicals
Solvents – Waste Disposal

Organic solvents such as chlorobenzene or TCA (trichloroethane) and photoresist, should never be
aspirated or poured down the drain. Solvents must be poured into solvent disposal bottles. Never pour
acid for disposal into a solvent waster bottle because an explosion may result. Make sure chemical
disposal bottles are not overfilled. When a chemical disposal bottle is approximately 75% full:
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Loosely cap the bottle. DO NOT TIGHTEN THE CAP. This prevents accidental pressure buildup from breaking the
bottle.
Remove the label from the chemical disposal bottle. Enter the summary of contents to the peel-off label and place
on the bottle.
Chemicals for disposal placed in the Waste Chemical Cabinet must be labeled with contents and the
name of the lab member. Placing unlabeled chemicals for disposal in this cabinet is a violation of lab
policy, which may result in suspension from the Microfab. You must fill out the Chemical Disposal
Manifest Sheet located on top of the disposal cabinet. The bottles are picked up by the BSU
Environment, Health and Safety Department. Notify the Microfab office if the storage area is full.
Use a safety carrier if the bottle is glass. Rinse bottles thoroughly 3 times under the fumehood. This will
prevent exposure to volatile compounds while rinsing bottles. Wear a face shield and chemical resistant
gloves while doing so. Once the bottle has been rinsed 3 times, black out the label with a marker. The
scratched label indicates that the bottle has been properly rinsed.
Collected in containers for pick up by Environmental Safety Services. Small incidental quantities should
be rinsed down the drain with copious amounts of water. For questions about waste solvents, contact the
lab manager. Do not dump solvents down the drains.
It is very important to clean up solvent spills in order to minimize the fire hazard and the amount of
vapors present in the lab. If you find a spill and can not identify it, contact the lab manager. The spilled
chemical needs to be identified before it can be cleaned up.
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Idaho Microfabrication Laboratory
ACCIDENTAL SPILL CONTAINMENT
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Idaho Microfabrication Laboratory
Chemical Spill Clean-up
 Small chemical spill (4L or less)
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Test spill pH with litmus paper if chemical is unknown before
proceeding.
Clean up spill with chemical spill pillows or blankets.
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Spill pillows & blankets are designed to be very absorbent and neutralize
acid spills.
Dispose of waste in appropriate bin.
 Large chemical spill
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New policy – CALL 911!
Notify lab manager at once!
Leave lab immediately.
For VERY large chemical spills, pull emergency fire alarm on your
way out the door.
Use your best judgment; if the spill is going to put anyone else in
the room and/or building in danger, act accordingly.
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Idaho Microfabrication Laboratory
What to do when you notice or smell
trouble in the cleanroom
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If there is a strong chemical odor coming from the cleanroom
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Do…….
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Do Not…….
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Dial 911 first then contact the cleanroom manager and others on the emergency
contact list.
exit the cleanroom and post a “DO NOT ENTER” sign on the door.
Enter the cleanroom in a attempt to determine what the source of the odor is.
Try and clean-up the spill.
If there is a large amount of unidentified liquid on the cleanroom floor
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Do………
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Call 911!
Contact the cleanroom manager and others on the emergency contact list.
Do Not………..
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Enter the cleanroom in an attempt to locate the source of the liquid.
Try and cleanup the spill.
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Idaho Microfabrication Laboratory
HAZARDOUS GASES
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Idaho Microfabrication Laboratory
Cleanroom Process Gases
 Cylinders of both toxic and non-toxic compressed gases are
in use throughout the lab.
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Only well trained students or staff may not install or disconnect these
cylinders.
Some gases in these cylinders are at high pressures (1500psi).
Improper installation or purging will contaminate a full bottle of gas.
Some of our etching gases cost hundreds of dollars and their loss or
contamination is very costly.
 Gas cylinders must be chained and strapped down at all
times.
 Precautions

The large volume of gas produced from evaporation of a liquid can
displace sufficient oxygen in a closed room to be dangerous (nitrogen
asphyxiation). Ensure you have adequate ventilation for any operation
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consuming or transferring liquid nitrogen or helium.
Idaho Microfabrication Laboratory
Cleanroom Hazardous Gases
Compressed Gases
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Handle cylinders of compressed gases as high-energy sources and therefore as potential
explosives.
Cylinders must not be dragged or rolled. Cylinders should not lean on one another.
Restrain cylinders of all sizes, empty or full, individually by straps, chains, or a suitable
stand to prevent them from falling.
Do not expose cylinders to temperatures higher than approximately 50C. Some small
cylinders, such as lecture bottles, are not fitted with rupture devices and may explode if
exposed to high temperatures.
Cylinders should be stored in appropriately ventilated closets or in an open storage area.
Store gases according to chemical compatibility .
Never store a cylinder next to a heat or flame source.
Do not place gas cylinders such that there is contact with electrical circuitry.
Never use cylinders that cannot be identified positively.
Inspect cylinder valves for damage or corrosion prior to use. If unsuitable for use, return to
supplier
Never lubricate or modify the cylinder valves.
Do not put oil or grease on the high pressure side of any oxygen, chlorine or other oxidizing
agent cylinder valve. A fire or explosion can result
Use the appropriate regulator on each gas cylinder. The threads on the regulators are
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designed to avoid improper use. Do not use any adapter between the gas cylinder and the
regulator.
Idaho Microfabrication Laboratory
Cleanroom Hazardous Gases
Compressed Gases
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Use toxic, flammable, corrosive, or reactive gases in fume hoods only. Post signs in the
laboratory area when using any of these type gases.
Never bleed cylinders completely empty. Leave a slightly positive pressure (30 psi) to keep
contaminants out. (Never heat a compressed gas cylinder to "milk" out the last bit of gas.
The base plug softens and it becomes a missile.)
Remove the regulator from an empty cylinder and replace the protective cap. Mark the
cylinder "empty" and place it in the appropriate location for pickup. Notify Microfab Staff.
Do not mix gases within a cylinder. If a mixture is required, order it that way from the
supplier.
Never open a cylinder more than 1/2 to 3/4 of 1 turn. This way the cylinder can be turned
off quickly in the event of an emergency.
Review the MSDS sheets for the gasses that you are using. Many of the gasses are toxic.
All high pressure gasses, regardless of toxicity, should be treated with respect.
Before using any gas on any piece of equipment, verify that the gas that you think is
connected is the one that actually is connected.
Always wear safety glasses when handling compressed gases.
Make sure all cylinders are properly labeled.
Never direct high pressure gases at a person
Regulators, gauges, and hoses should not be interchanged among gases.
Do not place any item on top of a cylinder that could damage a safety device or interfere
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with quick closing of a valve.
Idaho Microfabrication Laboratory
Cleanroom Information Tools
 IML Website
http://coen.boisestate.edu/IMFL/index.html
 designed to be used as a reference guide for cleanroom
operations.
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•
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Safety procedures – coming soon!
Equipment operating procedures
General semiconductor processes - WIP
Chemical inventory
Cleanroom chemical data sheets
 Lab manual – coming soon!
 Comprehensive manual for cleanroom users.
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Idaho Microfabrication Laboratory
Emergency Contacts
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Peter Miranda, Lab Director x65713 or 447-6636
Rex Oxford, interim COEN Facilities Manager, x65744
Dr. Amy Moll, COEN/MSE Faculty x65719
Dr. Bill Knowlton, COEN/MSE Faculty x65705
Jim Stevenson, Staff Engineer x65757
Cal Gillis, BSU Environmental Health Officer, x63999
All MAJOR spills must be reported to the Boise Department
of Public Works.

Boise Department of Public Works Contact List
•
•
Walt Baumgartner, Senior Environmental Specialist 343-3991
Mike Hunter, Pretreatment Program Director 384-3993
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Idaho Microfabrication Laboratory
THE END
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