COPETM

Motorola

Selectfluor®

NF3

Penn State

PITA

Development of the COPE^TM Process

In 1985, Air Products and Chemicals, Inc. and Goar, Allison & Associates Engineered Systems, Inc. jointly developed the Claus oxygen-based process expansion (COPE) process. This proprietary technology uses pure oxygen to expand the capacity of an existing Claus sulfur recovery plant up to twice its nameplate capacity.

This collaboration was initiated when Conoco contacted Goar, Allison & Associates, experts in sulfur plant design, for options to increase the capacity of existing Claus plants. Goar, Allison & Associates called upon Air Products, a leading supplier of oxygen, to help develop a process. LD Duiker, a burner company was also contacted to assist in that aspect of the technology. The first unit was brought onstream at the Conoco Lake Charles refinery within 18 months of the initial discussions between Goar, Allison & Associates and Conoco.

Today, as environmental standards on sulfur dioxide emissions continue to become more stringent, sulfur recovery plants are often fully loaded, sometimes overloaded. Incorporation of the COPE process eliminates the need to build expensive new sulfur plants. Recently, a new enhancement to the process has been developed and is currently being implemented on two Claus plants at the Conoco, Lake Charles refinery.

Reducing Process Emissions Associated With Semiconductor Manufacturing

Air Products has worked with Motorola, Inc. (Austin, TX ) to reduce process emissions during chemical vapor deposition (CVD).¹ After thin film deposition, CVD chambers must be cleaned using a plasma etch process. Presently, perfluorocarbons (e.g., C₂F₆) are used as etchant for installed equipment. Since perfluorocarbons are strong infrared absorbers and have long atmospheric lifetimes (e.g., 10,000 years for C₂F₆), they have a high global warming potential (GWP). Furthermore, perfluorocarbon plasmas generate additional perfluorocarbons byproducts (e.g., CF₄) during the chamber clean.

An alternative plasma source using NF₃ was evaluated for CVD chamber cleaning: remote plasma clean. Motorola installed the plasma source on CVD chambers at MOS11 and MOS13 and optimized the process through a design of experiments (DOE). Clean times were 65% faster than the baseline C₂F₆-based process. Air Products has developed analytical methods for monitoring semiconductor processes. Quadrupole mass spectrometry (QMS) and Fourier transform infrared (FTIR) spectroscopy measurements at Motorola determined process emissions during CVD chamber cleaning. The NF₃ utilization of the remote plasma clean was better than 99% and, unlike fluorocarbons, no additional high-GWP byproducts were generated. Marathon testing by Motorola showed no impact on the CVD film as many wafers were processed.

Remote plasma cleaning has been implemented in production, helping Motorola to achieve their targets for emissions reduction. This solution is applicable to the Electronics industry's installed base of CVD equipment. Besides reducing environmental impact, remote plasma cleaning using NF₃ improves the productivity of the CVD equipment by reducing the clean time.

¹ "Reduced Clean Time and PFC Emissions Reduction Through Remote Plasma Clean for Lamp Heated CVD Chambers," L. Mendicino, Electrochem. Soc. Meeting (2001).

Development and Commercialization of Selectfluor®

In 1989, a new family of electrophilic fluorination agents was invented that simplified the production of fluorinated pharmaceuticals. The discovery of the Selectfluor® fluorination agent family and the subsequent development of a commercial product evolved through interactions between scientists at Air Products, a British chemistry professor, and pharmaceutical researchers around the world.

For decades, synthetic chemists have added fluorine to certain pharmaceuticals to dramatically improve their biological activity and, hence, effectiveness as medicines. However, due to the difficulties in synthesizing selectively fluorinated compounds, the pharmaceutical industry has long sought for an easier, more economical way to manufacture fluorine-containing drugs.

In the late 1980s, Air Products, an experienced manufacturer of fluorine, sought to expand its fluorine business by developing new fluorine products for the pharmaceutical industry. They recruited the help of Professor Eric Banks of the University of Manchester Institute of Science and Technology, an international expert in fluorine chemistry. Professor Banks synthesized the family of compounds later marketed under the Selectfluor® name. Following the discovery of these promising fluorinating agents, chemists and engineers at Air Products developed a process for large-scale production.

Today, Selectfluor® is produced at the company's facility in Hometown, Pennsylvania and is used by several major pharmaceutical companies, primarily for the selective fluorination of steroidal pharmaceuticals.

Development of Microelectronic Applications for NF₃

Air Products and Chemicals, Inc. and Pennsylvania State University have been long-time collaborative partners in technology initiatives. One of the earliest successful collaborations was the development of applications for NF₃ in the microelectronics industry.

In the early 1980s, the microelectronics industry began to look at switching from conventional wet etching with liquid acid to dry etching with gases, to enable the manufacture of more sophisticated silicon chips. At the same time, Air Products was looking for microelectronic applications for its products. Air Products undertook a joint research project with Penn State engineers because of their understanding of electronics processing technology. One of the gases studied by Penn State was nitrogen trifluoride (NF₃). Air Products produced NF₃, but it had never been used in the electronics industry. Penn State demonstrated that NF₃ is a very effective etchant.

Today, NF₃ is used extensively for etching and chamber cleaning in the microelectronics industry. Air Products is the largest producer of NF₃ globally.

The benefits of this relationship to Air Products have been significant. An assessment in 2002, based on 33 projects, estimated that on average each project saved one-to-two years of internal R&D time and several hundred thousand dollars of net R&D funds. Over 30 percent of the projects resulted in the development of new research options and initiatives with potential annual sales in the millions of dollars. Air Products also identifies, through the unique Directed Fellowship Program, the best graduate candidates conducting research in fields aligned with our strategic needs. The program has supplied Air Products with three fellows so far.

• Combining physical and informational infrastructure technology development expertise in Pennsylvania
• Leveraging complementary technology development in design, manufacturing, and environmental issues.
• Focusing research and educational capabilities of two world-class universities on technology solutions to economic issues in the Commonwealth.
• Creating an environment linking Pennsylvania companies with students to create high paying jobs and retain highly educated students.