Corporate Environmental Report

Pollution

Air emissions: phase out all Class 1 ODS by the end of 1996. Contribute where we can to the reduction of greenhouse and acid rain generating gases.

All Class 1 Ozone Depleting Substances were eliminated by 1993 from production processes; by 1997 in all large refrigeration units (chillers) and since February of 1998 from fire-fighting systems.

These actions required an investment of some $20 million. The final step, now in progress, is to phase out all the remaining Class 1 ODS still present in some small equipment as well as in the air conditioning system in a newly acquired building in Phoenix, Arizona.

NEW ODS: phase out all remaining Class 1 ODS included also in closed loops of small equipment before end 2001.

Manufacturing sites emit pollutants such as acids, alkalis and solvents to the air. At most ST manufacturing facilities, site scrubbers have been installed to abate these emissions. All scrubbers are equipped with variable frequency drives to conserve energy and to maintain a standard exhaust pressure for the fab equipment.

In 1999, for the first time, a model for the calculation of the dispersion of pollutant gaseous emissions at ground level was applied at ST's Agrate, Italy site. In cooperation with Milan University, ST evaluated the gaseous emissions' impact on the surrounding environment using the US Environmental Protection Agency's computerized air dispersion model. This methodology goes beyond a simple measurement at the emission point and through modern and sophisticated evaluation criteria, provides a basis for optimizing investments as well as anticipating possible new laws from the regulatory authorities.

The new 8-inch fab now starting up in Rousset, France, will have very advanced methods for treatment of air emissions. Some 80 dedicated abatement systems will be installed at points of emission. In case of accidental toxic gas problems, sudden release systems can store leakage (chlorine, ammonia, hydrides) of complete containers. The general exhaust network in place has four different ducts - acid, ammonia, solvent and heat, and allows for the treatment of different emission types.

The main parameters to be controlled will place the site among the most advanced in this field and are shown below.

	SO2	: less than 0.5 mg/Nm3
	NF	: less than 0.2
	NH3	: less than 0.5
	VOC	: less than 35

NEW PFC: reduce emissions of PFC (tons of carbon equivalent per millions dollars of added value) by at least a factor of 10 in 2008 versus 1995.

The semiconductor industry currently emits fluorocarbons (CF4, C2F6, CHF3, C3F8), nitrogen trifluoride (NF3), and sulphur hexafluoride (SF6) from its manufacturing process. These gases, collectively referred to as perfluorinated compounds (PFC) are used in two important steps of semiconductor manufacture: plasma etching of thin films and cleaning Chemical Vapor Deposition (CVD).

Due to their high global warming potential and long atmospheric lifetimes, PFCs are now included in the Kyoto Protocol framework.

In 1999 the Company established an Emission Reduction Roadmap which includes : various technical solutions such as the process optimization of recipes consuming PFCs; an upgrade of the main Chemical Vapor Deposition (CVD) and etching tolls; retrofitting to bring reduction of PFC emissions; and the installation of abatement systems with high destruction removal efficiency. The global objective for ST is to reduce emissions in tons of carbon equivalent per million dollar of added value by at least a factor of 10 by the year 2008 versus 1995. If this objective is reached, in absolute terms, it will be a reduction of more than 10% in 2008 compared to the 1995 baseline.

With the common goal of reducing PFC emissions, ST is working with many different international organizations:

	EECA (European Electronic Components Manufacturers Association) Semiconductor Environmental Taskforce (Leadership of the Technical Working Group);
	WSC (World Semiconductor Council) Taskforce;
	PFC leadership Working Group (United States);
	Close contact with national authorities in countries where ST operates.

In 1999, the Company's main efforts were concentrated on the conversion from C2F6 to C3F8. Substantial benefits resulted:

	The Singapore Fab 3 at Ang Mo Kio converted five of nine P5000 oxide tools, reducing the consumption of wet cleaning gas by 42% and PFC emissions by 67%. Significant cost reduction through increased tool uptime and reduction of wet clean frequency were also achieved. At the Ang Mo Kio Fab 4, Low Pressure Chemical Vapor Deposition tools were converted to C3F8, bringing a reduction in PFC emissions of 77%.
	At Phoenix, Arizona, the full C3F8 implementation on the P5000 process was completed resulting in significant benefits both in cost savings of $100,000 and PFC emission reduction of 30%.
	Another high priority program dealing with PFC emission is the implementation of the remote plasma clean using NF3 on tools. Some 95% reduction was achieved using this technology.
	In the field of abatement, numerous point-of-use abatement systems with high removal destruction efficiency have demonstrated 99% reduction at fabs such as Crolles in France, Catania and Agrate in Italy and at Rancho Bernardo in the US.
	In partnership with the Univerity of Bari, the search for alternative compounds for Si02 etching is also being investigated by means of a home made reactor. HFCs with low global warming potential (CHF2, HFC134a and HFC 135) have been tested in a mixture with CF4 and 02. The results are promising, for CH2F2 in particular, as an alternative for replacing CHF3 in the conventional mix used for Si02 dry etching.