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Researchers from the Laboratoire de Physique
des Solides et de Cristallogenèse (Laboratory of Crystallogenesis
and Solid-State Physics, CNRS – Université de Versailles,
Meudon, France) have recently demonstrated for the first time that it
is possible to obtain a diamond with high electric conductivity provided
by electrons. These results have direct applications in the area of microelectronics.
They are published in the July issue of Nature Materials.
As a result of their exceptional physical
and chemical properties, diamonds are an invaluable semiconductor for
the manufacturing of electronic and optoelectronic* devices. However,
the fact that a type n** diamond with satisfactory electrical properties
does not exist has been a serious handicap in the production of such devices.
Researchers at the Laboratoire de Physique des Solides et de Cristallogenèse
have demonstrated for the first time that it is possible to obtain a type
n diamond with high electrical conductivity at room temperature. The operation
consists of diffusing hydrogen into the boron-doped diamond. A reversible
conversion from type p to type n is thus obtained. The type n electrical
conductivity values obtained are 10,000 times greater than those obtained
using the standard process (direct incorporation of phosphorus).
These results will contribute to greatly extending the scope of both basic
and applied research. Applications mainly concern high-temperature diamond-based
electronics (transistors, diodes, etc.) that will be necessary in the
future in the field of space exploration and the automobile industry,
as well as in the telecommunications and energy distribution sectors.
The CNRS has filed a patent application (Dec. 6, 2002) following these
findings.
Reference:
"Shallow donors with high n-type electrical conductivity in homoepitaxial
deuterated boron doped diamond layers." Zéphirin Teukam, Jacques
Chevallier, Cécile Saguy, Rafi Kalish, Dominique Ballutaud, Michel
Barbé, François Jomard, Annie Tromson-Carli, Catherine Cytermann,
James E. Butler, Mathieu Bernard, Céline Baron, Alain Deneuville.
Nature Materials, Volume 2, Issue 7 p482-486, July 2003.
* Optoelectronics is the area of physics that deals with relationships
between electronics and light radiation.
** A diamond is said to be of the n type if the electrical conduction
is mainly provided by electrons. The other type of conduction obtained
by incorporating boron atoms is known as type p.
Researcher
contacts:
Jacques Chevallier
Tel: +33 1 45 07 53 40/53 70
E-mail: jacques.chevallier@cnrs-bellevue.fr
Mathematics and Physical Sciences Department
contact:
Frédérique Laubenheimer
Tel: +33 1 44 96 46 23
E-mail: frédérique.laubenheimer@cnrs-dir.fr
Press Contact
CNRS:
Muriel Ilous
Tel: +33 1 44 96 43 09
E-mail: muriel.ilous@cnrs-dir.fr
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