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Gases affected
(reduced, recovered, destroyed, replaced, avoided)
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HFC-23; CF4; C2F6; C3F8; SF6 and NF3*
*The Semiconductor industry uses NF3 which has been identified as a greenhouse gas with a 100-year GWP =
8,000 and atmospheric life of 740 years (Molina et al, Geophysical Research Letters, Vol. 22, 1873-6
(1995)) but is not yet listed by the IPCC.
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General description
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In 1996, the U.S. Environmental Protection Agency (EPA) joined with semiconductor manufacturers to form the
PFC Emission Reduction Partnership for the Semiconductor Industry. The voluntary partnership aims to reduce
emissions of atmospherically long-lived perfluorocompounds from semiconductor manufacturing. Companies
joining the Partnership have agreed to work to reduce their emissions by considering the viability of
pollution prevention techniques such as process optimization, source reduction, substitute chemicals,
recovery/recycling, and abatement. This Partnership is an important step in the U.S. effort to control
emissions of long-lived, greenhouse gas emissions.
The semiconductor industry uses HFC-23, CF4, C2F6, C3F8, SF6, and NF3 in two important production
processes-- plasma etching thin films and plasma cleaning chemical vapor deposition (CVD) tool chambers.
These chemicals are critical to current manufacturing methods because they possess unique characteristics
when used in a plasma that currently cannot be duplicated by alternatives. There are no known zero-GWP
substitutes for these chemical in these applications. The industry’s technical reliance on high GWP
gases has increased significantly in the past several years. This reliance is expected to increase due to
rapid industry expansion to meet growing demand for semiconductor devices, and ever increasing complexity
of semiconductor devices which require increased PFC use. However, voluntary action through the U.S.
semiconductor partnership and global industry collaboration through the World Semiconductor Council is
expected to result in significant reductions in emissions by 2010.
The U.S. voluntary partnership is implemented through a Memorandum of Understanding (MOU) which details the
roles of both EPA and the Partner to reduce emissions. The MOU was developed in collaboration with the U.S.
Semiconductor Industry Association (SIA). Partners agree to estimate PFC emissions beginning in 1995;
estimate annual emissions using an emissions inventory protocol; submit annual progress reports; and set
technically feasible, cost-effective emission reduction targets. EPA acts as a clearinghouse for technical
information on successful strategies to reduce PFC emissions; provides partners with recognition for their
achievements in reducing PFC emissions; serves as a repository for data on the emissions reduction
achievements of the partners; and pursues commitments from all manufacturers operating in the U.S. to join
the partnership. The tracking and reporting scheme implemented under the Semiconductor Partnership enables
participants to document their early contribution to the prevention of global climate change.
In 1998 Japan became the first country to establish PFC emission reduction goals for the semiconductor
industry. In that same year, IBM became the first U.S. semiconductor manufacturer to publically announce a
comprehensive climate goal including a target for PFC emissions reduction. These actions energized industry
to think globally and to use goals to motivate suppliers and customers to support climate protection.
Generally, process tools consume from 15-60% of influent PFCs depending on the chemical used and the
process application (etch or CVD). PFC emissions vary depending on a number of factors: gas used,
type/brand of equipment used, company-specific process parameters, number of PFC-using steps in a
production process, generation of PFC by-product chemicals, and whether abatement equipment has been
implemented. Product manufacture and production processes and, consequently, emissions vary widely from fab
to fab. To further reduce emission levels, process optimization, alternative chemicals, capture/recycling
and effluent abatement are all being considered. The size of wafers being processed in a semiconductor
fabrication facility (fab) and the fab’s design and age also have a major impact on PFC emissions
reduction technology applicability. Existing fabs may have insufficient infrastructure and space to
implement some emission reduction technologies. For new and planned fabs, purchasing state of the art
process equipment that optimizes PFC use and employs alternative chemistries is expected to be the best
option.
The U.S. Semiconductor Partnership is complemented by global action by the semiconductor industry to reduce
PFC emissions. The World Semiconductor Council is coordinating a global initiative to reduce emissions
which includes participation of companies in Europe, Japan, Korea, Taiwan and the United States. At their
third meeting in Fuiggi, Italy in April 1999, the World Semiconductor Council (WSC) agreed to reduce PFC
emissions by at least 10 percent below 1995 levels (1997 for Korea) by 2010. The WSC emission reduction
goal will result in significant benefits to the climate and demonstrates the effectiveness of voluntary
action by industry and governments. The WSC was formed in 1996 to address market access issues and promote
industry cooperation on economic, trade and environmental concerns that face the global semiconductor
industry. Through the WSC, the semiconductor industry is working together to develop, evaluate and share
information on emission reduction techniques, provide a common message to equipment and chemical suppliers
on the need to minimize emissions, and to set measurable emission reduction goals. The WSC includes the
Semiconductor Industry Association (SIA) of the United States, the European Electronic Component
Manufacturers Association (EECA), the Electronic Industries Association of Japan (EIAJ), the Korea
Semiconductor Industry Association (KSIA), and the Taiwan Semiconductor Industry Association (TSIA). WSC
members produce over 90 percent of the world’s semiconductors. EPA and the Japan Ministry of
International Trade and Industry (MITI) have actively supported and encouraged the WSC agreement.
Semiconductor industry actions to reduce emissions are outlined as follows:
1980s PFCs identified as effective etch and plasma cleaning chemicals
1990s PFCs identified as potent greenhouse gases
1996 U.S. EPA forms voluntary PFC emission reduction partnership
EPA and MITI organize Japan PFC Pathfinder Meeting
Voluntary partnerships organized in Japan and Europe
1998 Japan announces PFC emission reduction goals for electronics industry
Voluntary partnership organized in Korea
1st International PFC Emission Reduction Conference, Monterey, California
World Semiconductor Council cites PFCs as top environmental challenge
1999 World Semiconductor Council commits to global emission reduction goal
Voluntary partnership organized in Taiwan
U.S. Voluntary Partners
Advanced Micro Devices
American Microsystems (AMI)
Burr-Brown
Cherry Semiconductor
Digital Equipment
Dominion Semiconductor
Eastman Kodak
Hewlett-Packard
Hitachi Semiconductor
IBM
Intel
LSI Logic
Lucent Technologies
Micron Technology
Motorola
National Security Agency
National Semiconductor
NEC Electronics
Philips electronics
Rockwell Semiconductor Systems
Sony Semiconductor
ST Microelectronics
Texas Instruments
VLSI Technology
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