Media Advisory

Producing a material that is harder than natural diamond has been a goal of scientists for decades. Now a group headed by geophysicist Russell Hemley of the Carnegie Institution of Washington (D.C.), has produced gem-sized diamonds that are harder than any other crystals. The scientists made the diamonds at a rate 100 times faster than other methods used to date. The process opens up a new way of producing diamond crystals for electronics, cutting tools and other applications.

Hemley and colleagues developed a special high-growth-rate chemical vapor deposition (CVD) process to grow the diamond crystals. They then subjected the crystals to high-pressure, high-temperature treatment to further harden the material. The method has been used to "grow" diamonds up to 10 millimeters across and 4.5 millimeters thick. The crystals are at least 50 percent harder than conventional diamonds; the diamonds were so hard they broke the scientists' measuring equipment. The researchers were able to grow the gem-sized crystals in a day.

In celebration of Earth Day 2004, Hemley will speak at the National Science Foundation, which funds the team's research, about the CVD process and the resulting super-diamonds.

For more information and to obtain a pass for entrance into the NSF building, please contact:

-NSF-

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering, with an annual budget of nearly $5.58 billion. NSF funds reach all 50 states through grants to nearly 2,000 universities and institutions. Each year, NSF receives about 40,000 competitive requests for funding, and makes about 11,000 new funding awards. The NSF also awards over $200 million in professional and service contracts yearly.

Receive official NSF news electronically through the e-mail delivery system, NSFnews. To subscribe, send an e-mail message to join-nsfnews@lists.nsf.gov. In the body of the message, type "subscribe nsfnews" and then type your name. (Ex.: "subscribe nsfnews John Smith")

Useful NSF Web Sites:
NSF Home Page: http://www.nsf.gov
News Highlights: http://www.nsf.gov/od/lpa
Newsroom: http://www.nsf.gov/od/lpa/news/media/start.htm
Science Statistics: http://www.nsf.gov/sbe/srs/stats.htm
Awards Searches: http://www.fastlane.nsf.gov/a6/A6Start.htm

This photograph shows a synthetic brilliant cut single-crystal diamond grown by chemical vapor deposition, CVD. About 2.5 mm high, this crystal was grown in about 1 day at Carnegie. The very bottom (table) of the crystal is a type 1b seed: hence the yellow tint which is due to internal reflection (the CVD diamond is transparent). [C.S. Yan et al., Physica Status Solidi (a) 201,R25 (2004)(PDF 288KB)]. The researchers have also reported that these CVD diamonds are capable of easily generating ultrahigh pressures to at least 200 GPa.[W.L. Mao et al., Appl. Phys. Lett. 83, 5190 (2003)(PDF 288KB)].
Credit: Image used with permission of Physica Status Solidi.
Select image for larger version
(Size: 227KB)

 Note About Images