Corporate Environmental Report

Emissions to air

Ozone depleting substances (ODS): phase out all remaining Class 1 ODS included also in closed loops of small equipment, before end 2001

All Class 1 Ozone Depleting Substances were eliminated from production processes by 1993; by 1997 from all large refrigeration units (chillers); and since 1998 from fire-fighting systems. These actions required investments of some $20 million. The phase out of all the remaining Class 1 ODS still present in some small equipment was successfully achieved as well as the ODS present in the air conditioning system in an acquired building in Phoenix, Arizona.

Many semiconductor manufacturing process use chemicals and gases that can be harmful to the environment. For example, the wet etch process uses acids such as Hydrochloric Acid, Hydrofluoric Acid, or Sulfuric Acid. Without treatment, emissions could acidify the environment.

Scrubbers are installed at most of our manufacturing facilities to abate emissions, such as as acids, alkalis and solvents. All scrubbers are equipped with variable frequency drives to conserve energy and to maintain the standard exhaust pressure needed by the equipment.

Examples

	At our Carrollton site in Texas, USA, a system was installed in 2000 to segregate acids, VOCs and ammonia exhaust for treatment. Over 95% of all VOCs are removed through absorption and extreme heat - an approach being adopted at other ST sites worldwide.
	At our Agrate site in Italy, a system was installed in 2000 to segregate VOC exhaust and to reduce other air emissions. Inorganics were reduced from 8.2 tonnes/year to 0.79 tonnes/year. Powders were reduced from 1.17 tonnes/year to 0.54 tonnes/year.

PERFLUORINATED COMPOUNDS (PFCs)

PFC: reduce emissions of PFC (tonnes of carbon equivalent per M$) by at least a factor of 10 in 2008 versus 1995

Perfluorinated compounds (PFCs) - widely used in the semiconductor industry - are very stable, non-toxic, ozone-benign substances that have a long life in the atmosphere and contribute to climate change.
Our industry uses several types of PFCs with Global Warming Potentials ranging from 6,500 to 23,900 times the carbon dioxide equivalent.

ST leads the European task force of the World Semiconductor Council (WSC) which has set a challenging goal to reduce the aggregate absolute PFC emissions from the industry to 10% below 1995 levels, by 2010. Twenty four companies have signed a Memorandum of Agreement to share all technical information on PFCs and to report results and progress according to the international standards developed by the Intergovernmental Panel for Climate Change (IPCC).
Experts have suggested three major solutions:

	Process optimization to reduce PFC consumption and emissions
	Use of alternative chemicals
	Abatement systems that destroy most (more than 95%) of the PFC emissions

We will contribute to this program by reducing our PFC emissions by 10% below 1995 levels, by 2008 - at least two years before the WSC deadline. More than 60 PFC abatement systems have already been installed.

Alternative compounds, such as C3F8 (reduces emissions by 40-70%), are being used in several of our locations, in the USA, France and Singapore. New equipment using an alternative called NF3 (can cut emissions by 95%) is operating in our advanced manufacturing sites.

We are working in partnership with universities to research alternative compounds. New solutions, such as plasma abatement technologies, are being tested in Rousset, France, Agrate and Catania in Italy, and Phoenix USA. Catalytic absorption systems are being tested in Catania, Italy.

Although absolute PFC emissions (expressed in carbon-equivalent) have increased due to the growth in manufacturing output, there has been a 35% reduction in PFC emissions per wafer produced between 1995 and 2000. PFC emissions per $million of added value dropped 30% down between 1995 and 2000.