Transcript SeminarPresentations\HandlingOfToxicMaterialsAdamSchmolling

Handling and
Remediation of Toxic
Materials
By Adam Schmolling
April 29, 2016
Abstract: The semiconductor industry uses a number of harmful chemicals.
This presentation covers the handling of these chemicals.
This presentation will:
Introduce the chemicals, and what they do to humans.
Outline how these chemicals are used in the semiconductor
manufacturing process.
Explain how manufacturers are handling these chemicals.
Cover environmental issues in third world countries.
Address what manufacturers are considering to further clean
up the semiconductor manufacturing process.
Some of the harmful chemicals
used:
Acetone
Arsenic
Arsine
Benzene
Cadmium
Methyl Chloroform
Phosphine
Toluene
Trichloroethylene
Acetone
An industrial solvent.
Used in the polishing of silicon wafers.
OHSA PEL: 500 ppm
OSHA STEL: 750 ppm
OSHA CEILING: (immediate danger) 3000 ppm
Arsenic
Used in rat poison.
Used as a dopant in semiconductors.
OSHA PEL: 10 micro grams / m3
Arsine
Gas made with Arsenic
Used for vapor deposition
In route through inhalation
Garlic / fishy smell,
which does not provide enough warning
Flammable and highly toxic
OSHA PEL: 0.05 ppm
Benzene
Used in photo-electrochemical etching
Has the famous Benzene ring
Sweet aromatic odor
Used extensively in assorted industries
Liquid at room temperature, but
evaporates into air quickly.
Cadmium
Used as a dopant
Banned by EU
Causes a number of ailments
Methyl Chloroform
Used in washing of silicon wafers
OSHA PEL: 350 ppm
OSHA STEL: 450 ppm (for 15 minutes)
Immediate danger: 700 ppm
Phosphine
Used in vapor deposition
Flammable, toxic and Pyrophoric
Immediate danger limit: 0.3 ppm
Toluene
Used for chemical vapor deposition
Sweet, pungent odor, which provides
Enough warning.
OSHA PEL: 200 ppm
OSHA ST: 500ppm (for 10 minutes)
Gas at room temperature
Trichloroethylene
Used for wafer washing
Liquid at room temperature
May decay into Dichloroacetylene,
which is explosive and a neurotoxin.
OSHA PEL: 100 ppm
Assorted Acids
Hydrofluoric Acid
Sulfuric Acid
Nitric Acid
Orthophosphoric Acid
Hydrochloric Acid
Hydrobromic Acid
Silane
Used in chemical vapor deposition
Silane leaks can be very dangerous
Spontaneously ignites when mixed
with air (without flame or spark.)
Pyrotechnics
Pyrotechnics
Pyrotechnics
Residue
Leaves a brown residue
which is composed of SiH2O
and a white residue composed
of SiO2
Silane explosions in the
semiconductor industry
1976, Germany
1989, Japan
1990, Japan
1992, United States
1996, Japan
2003, United States
2005, Taiwan
Chemical Handling Concerns
1981: Leaky underground storage tanks in San Jose, CA.
In 1990, 70 female workers in Scotland brought a lawsuit
against National Semiconductors.
1995: The American Journal of Independent Medicine
studied miscarriage among semiconductor industry workers.
1996: IBM employees brought a lawsuit against various
chemical manufacturers.
2014: Samsung publically apologized for worker deaths.
Samsung Worker Deaths and
Illnesses in Korea
Handling of Dangerous Wastes
There is a three part strategy for dealing with the waste
chemicals of semiconductor manufacturing:
1. Waste Elimination
2. Waste Reduction
3. Waste Treatment
Gas Monitoring
PPM detectors in ventilation, gas cabinets, enclosures etc.
Flammable gas monitoring
Containers of hazardous gasses are isolated
State of the Art Gas Monitoring
System
Actually
Plant Exhaust System
Making things “Green”
Fairchild Semiconductors is striving to become more
environmentally friendly.
Texas Instruments is very proud of their LEED certified
fabrication plant in Richardson, Texas.
PPM Limits (Per Product)
PPM Limits Continued
Water Use
Ultra Pure Water (UPW) is used
It takes 1600 gallons of tap water to make 1000 gallons of
UPW
It takes 1500 gallons of UPW to create a single 30cm wafer
A typical fabrication plant can use 4 million gallons of UPW
water per day.
Water Use
This is an environmental, as well as an economic concern.
Especially in China, who is a leader of semiconductor
manufacturing, and also has a growing thirst for clean water.
Sometimes environmental regulations are skirted.
Conclusion
The semiconductor industry uses a number of dangerous
chemicals. These chemicals must be carefully handled, and
care must be taken to avoid contaminating the environment
or endangering workers.
References
[1]
electronicstakeback.com [online]
Available: http://www.electronicstakeback.com/toxicselectronics/wheres-the-harm-component/
[2]
in-
electronicstakeback.com [online]
Available: http://www.electronicstakeback.com/2014/05/27/samsungapologizes-to-semiconductor-workers-who-contracted-cancer-promisescompensation/
[2]
chinawaterrisk.org [online]
Available: http://chinawaterrisk.org/resources/analysis-reviews/8things-you-should-know-about-water-and-semiconductors/
[3]
prevor.com [online]
Available: http://www.prevor.com/en/chemical-risks-insemiconductors-industry
References
[5]
cnx.org [online]
Available: http://cnx.org/contents/7238FjUe@3/The-EnvironmentalImpact-of-th
[6]
semi.org [online]
Available: http://semi.org/en/ti%E2%80%99s%E2%80%9Cgreen-fab
%E2%80%9D-cost-30-less-%E2%80%94- and-will-save-4-million-year-0
[7]
controlinstruments.com [online]
Available: http://www.controlinstruments.com/
documents/hazardousgas-monitoring-throughout-semiconductor-manufacturing-facility
[8]
S. Virgil, “Environmental Management of Wastes in the Semiconductor and
Electronics Industries,” Proceedings of International Symposium on
Advanced Waste and Emission Management. Dec. 4, 2000 pp 2-7
Five Key Points
Silane and Phosphane need no spark to ignite, but can
spontaneously ignite when exposed to the atmosphere.
If safety standards are skirted, workers can end up with Leukemia,
liver problems, and a host of other long term ailments.
The semiconductor industry currently consumes large quantities of
water. Ways to reduce water consumption are continuously being
investigated.
The three level strategy to reducing dangerous waste is
elimination, reduction, and treatment.
Infinitesimally small amounts (0.05 – 0.3 ppm) of Arsine and
Phosphine are lethal.