Transcript Environmental Cost of Integrated Circuit Manufacturing

By: Andrew Dyck, Dilan Pauli
What is an Integrated Circuit(IC)?
An IC is an electronic circuit that is used
in virtually all electronic equipment.
 It has helped revolutionize the world of
electronics.
 The low cost of integrated circuits has
made personal computers, mobile
phones, and any other digital machine
possible.

What is an IC made of?
An IC is made up of trace elements into
the surface of a semiconductor material.
 The other materials will then be
deposited and used in a pattern to form
interconnections between devices.
 Silicon monocrystals are the main
substrate for IC manufacturing.

What is an IC made of?

Some other materials are used for more
specialized applications, such as gallium
arsenide.
How are they manufactured?
Integrated Circuits are developed in
what are known as fab plants, or
semiconductor fabrication plants.
 The most important room in fabrication
is known as the clean room, where the
environment is controlled to eliminate all
dust and outside contaminations.

How are they manufactured?
The people who work in these clean
rooms must be wearing bunny suits,
which completely seal them from the
environment around them.
 Despite this immaculate clean room,
there are health risks and environmental
risks as well.

What are the environmental
risks?
Silicon Valley, where a great portion of
IC fab takes place, have always had
environmental risks associated to them.
 The chemicals that are used in this
process are not very expensive, but the
rising costs of chemical disposal
contribute to environmental impact.

Environmental Risks

According to the information that we
gathered, a typical semiconductor fab
plant can use over a million gallons of
water every day.

These facilities can also use as much as
240,000 KWh(kilowatt hours) of
electricity.
Environmental Risks to Water
A facility producing 6 inch wafers can
use around ~2 million gallons of water a
day.
 A facility producing 8 and 12 inch wafers
can use ~5 million gallons of water a
day.
 While some recycling of water does
occur, to get it back in a re-usable state
there is extensive chemical treatment
required.

Environmental Risks to Water
Considering that most IC fab plants are
in such dry places like New Mexico,
Arizona, and California, this extensive
use of water can drain an already scarce
natural resource.
 From our sources, we learned that the
fabrication off just 1/8th of a wafer can
require 3,787 gallons of water as well as
27 pounds of chemicals and 29 cubic
feet of hazardous gases.

Past Environmental Issues
Contamination of water has always been
an issue in areas surrounding fab plans.
 A past example of contamination was
that in San Jose in 1981. Fairchild
Semiconductor and IBM’s underground
storage tanks leaked thousands of
gallons of toxic solvents into the ground.

Past Environmental Issues
After this incident, drinking water was
found to be contaminated with
trichlorethane and Freon, which are
toxins commonly used in semiconductor
fabrication.
 Now there are a number semiconductorrelated cleanup sites.

Other Environmental Issues?
What is done with these electronic
devices that contain semiconductor
devices when they are out of date or
broken?
 This is a serious issue in IC fabrication.
 More often than not, these devices are
just put into the trash and wind up in the
landfills, posing an environmental risk
because of the semiconductor devices
left inside of them.

Health Risks in the Industry
In the past there have been some
incidents including workers.
 Some employees who had been
exposed to carcinogenic and toxic
materials over the course of time had
died from cancer.
 The chemicals used in IC fab can cause
serious problems.

Health Risks in the industry
Some of the environmental contaminates are:
 Acetone
 Lead
 Arsenic
 Methyl
 Arsine
Chloroform
 Toluene
 Trichloroethylene
 Benzene
 Cadmium
 Hydrochloric Acid
IC manufacturing, concluded
The environmental effect of IC
manufacturing can and is a serious
issue.
 As future Electrical and Computer
engineers, it our job to work towards a
better solution so that we can improve
IC fabrication for future generations.

References
J. Holden,” The Environmental Impact of
the Manufacturing of Semiconductors”
http://cnx.org/content/m14503/latest/
 B. Pimentel, “The Valley’s Toxic History.”
San Francisco Chronicle 30 Jan. 2004,
final ed.: B1
 C. Hayhurst, “Toxic Technology:
Electronics and the Silicon Valley.” E:
the Environmental Magazine May-Jun.
1997: 4
