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Semiconductor Manufacturing: National Emission Standards for Hazardous Air Pollutants (NESHAP)

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Rule Summary

The Semiconductor Manufacturing source category includes operations used to manufacture p-type and n-type semiconductors and active solid-state devices from a wafer substrate. Research and development activities located at a site manufacturing p-type and n-type semiconductors and active solid-state devices are included in the definition of semiconductor manufacturing.  Examples of semiconductor or related solid-state devices include semiconductor diodes, semiconductor stacks, rectifiers, integrated circuits, and transistors.

The source category includes all manufacturing from crystal growth through wafer fabrication, and test and assembly.  The primary hazardous air pollutants that are controlled by this rule include but are not limited to, five chemicals that comprise over 90 percent of the total HAP emissions: hydrochloric acid (HCl), hydrogen fluoride (HF), glycol ethers, methanol, and xylene.

Rule History

07/22/2008 – Final Rule

10/19/2006 – Proposed Rule

05/22/2003 – Final Rule

05/08/2002 – Proposed Rule

Additional Resources

Semiconductor Manufacturing Final Air Toxics Rules Fact Sheets

Manufacture of Semiconductors - Background Information for Proposed Standards