However, while performing work at the University of Wisconsin-Madison, Sumant developed a system for depositing diamond thin films. The technique, called hot filament chemical vapor deposition, involves the heating of a tungsten filament (like those found in incandescent light bulbs) to over 2000 degrees Celsius.
If the diamond film is exposed to a flow of molecular hydrogen while sitting within a centimeter of the hot filament, the heat will cause the molecular hydrogen to break down into atomic hydrogen, which will react with the film's surface to create a perfectly smooth layer. Since this method does not require the use of plasma, there is no danger of ion-induced etching.
"We've proved that this is a gentler method of terminating a diamond surface," Sumant said.
Sumant said that he hopes to use the knowledge gained from the experiment to eventually discover a way to manipulate the friction of surfaces on the atomic level. Such a result would prove immensely valuable to the development of nanoelectromechanical systems, or NEMS, based on diamonds, one of Sumant's primary research interests at Argonne's Center for Nanoscale Materials.
|Contact: Steve McGregor|
DOE/Argonne National Laboratory