Making LCD TV and solar cell production environmentally friendly

Munich, July 16, 2008 – The technology company The Linde Group offers a unique solution to replace the powerful greenhouse gas nitrogen trifluoride (NF3) used in the production of LCDs (Liquid Crystal Display) and solar panels. Based on a proven technology, the innovative process utilizes on-site generation of fluorine gas, making production more efficient and more environmentally friendly.

There is currently a high level of attention on the usage of NF3 by the electronics industry because of the gas’ very high global warming impact. Linde has developed a state-of-the-art process to replace NF3 with pure fluorine, which has a zero global warming potential.

The process is applicable to the manufacturing of flat screen TVs and to the mass production of low cost, thin film photovoltaic cells, which convert sunlight into electricity. Besides fluorine’s environmental advantage, it also improves performance and reduces costs in the chamber cleaning process, a critical step in the manufacturing of semiconductors, flat panels, and solar cells.

Tests carried out at Linde’s Application Development Lab in San Marcos, California, demonstrated that fluorine can significantly improve throughput in plasma activated cleaning, while qualification trials show that fluorine can reduce the cleaning time needed for NF3 on the same tool set. Faster cleaning of the manufacturing equipment eliminates a bottleneck process and gives customers a significant productivity improvement.

“Eliminating NF3 from LCD and solar manufacturing makes environmental and economic sense. Fluorine reduces non-productive cleaning time on the most expensive piece of equipment in the fab and improves customer throughput. It is a very good example of environmentally friendly solutions that also improve cost efficiency,” said Dean O’Connor, head of Solar Business, Linde Gases Division.

Linde is the leading supplier of fluorine, producing it on-site, on-demand and at very low pressures. Developed in the late 1990s, this proven technology has been used by Linde customers for fab-wide semiconductor applications since 2003 and can easily be applied to solar cell manufacturing.

“Linde is committed to delivering new processes that do not harm people or the environment,” said Paul Stockman, technology manager for Linde’s fluorine Business. “Our customers in LCD and solar manufacturing expect Linde, as their supplier, to help them drive down costs. By replacing NF3 with on-site fluorine we achieve both these objectives. This shows how Linde’s investment in engineering and technology solutions can enable mutual benefits for our customers and the environment.”

Linde’s on-site fluorine generators have been installed at more than 20 semiconductor, LCD and solar cell production sites, including Toshiba Matsushita Display, Samsung, and LG. This technology is particularly important for the solar panel industry, because it eliminates the environmental impact and makes the panels and the electricity they generate more cost-competitive.

About NF3
The greenhouse gas NF3 is 17,200 times more potent than carbon dioxide in contributing to global warming, yet it is not covered by the Kyoto protocol because it was only produced in tiny amounts when the protocol was agreed in 1997. Even today, its accumulation in the atmosphere is not being specifically monitored. Estimates from a study carried out by Michael Prather, lead author on the Nobel Peace Prize winning Intergovernmental Panel on Climate Change, predicts 4,000 tons of NF3 will be produced this year, with the amount doubling next year.

The gas is used in the electronics industry to flush out the by-products of chemical vapour deposition. Today’s flat screen TVs and computer monitors mostly use LCD panels made by depositing silicon and other materials in thin layers on large glass sheets. During the deposition process significant quantities of silicon are also deposited on the chamber walls, which can affect the quality of subsequent batches. The deposits are removed by splitting NF3 to release fluorine, which converts the solid silicon to a gaseous compound which is pumped away. Recently the electronic industry has adapted the LCD process for large scale, low cost production of thin film solar cells. With its expected growth, the solar cell industry looks set to be an even larger NF3 consumer. Such growth might lead to a six-fold increase in NF3 use by2020.

About The Linde Group
The Linde Group is a world leading gases and engineering company with more than 50,000 employees working in around 100 countries worldwide. In the 2007 financial year it achieved sales of EUR 12.3 billion. The strategy of The Linde Group is geared towards sustainable earnings-based growth and focuses on the expansion of its international business with forward-looking products and services. Linde acts responsibly towards its shareholders, business partners, employees, society and the environment - in every one of its business areas, regions and locations across the globe. Linde is committed to technologies and products that unite the goals of customer value and sustainable development.

For more information, see The Linde Group web site at www. linde.com

For further information:

Contact:
Steve Pilgrim
Phone: +44 1483 244791
Steve.pilgrim@linde.com

Stefan Metz
Phone: +49.89.35757-1322
stefan.metz@linde.com