AVS 50th International Symposium
    Contacts to Organic Materials Topical Conference Monday Sessions
       Session OM-MoM

Paper OM-MoM8
Direct Double-Bond Contacts to Metal Carbides: A New Surface Functionalization Reaction

Monday, November 3, 2003, 10:40 am, Room 318/319

Session: Contacts to Molecules and Molecular Films (I)
Presenter: P.H. McBreen, Universite Laval, Canada
Authors: M. Siaj, Universite Laval, Canada
H. Oudghiri Hassani, Universite Laval, Canada
P.H. McBreen, Universite Laval, Canada
Correspondent: Click to Email
Functional nanoelectronics devices require optimal electrical contact between their components as well as adequate protection from the environment. In the context of SWCNT-based field-emission transistor devices, metal carbides can be used as chemically bonded high-transmission source/drain contacts.@footnote 1@ We will present results showing that organic layers can be attached to the surface of molybdenum carbide via a metal-carbon double bond. This new surface reaction involves the insertion of a surface metal atom into the carbonyl bond of ketones or aldehydes, as in the following process; R2C=O + Mo yields R2C=Mo=O. Furthermore, the R2C=Mo surface groups (termed surface alkylidenes) are found to be thermally stable to above 900 K, if the surface is rendered inert though carbon deposition.@footnote 2@ The fact that the contact between the organic layer and the carbide is a double bond points to three advantages. First, a double bond is intuitively a better electrical contact than a sulfur atom. Second, it is possible to form carbides from a wide variety of metals. Third, we have demonstrated that alkylidene functionalized molybdenum carbide is active for metathesis reactions. Thus, ring opening polymerization (ROMP) can be used to grow polymeric layers directly from the carbide surface. Extensive results obtained using RAIRS and XPS will be presented to describe these new methods for the preparation of double bond contacts on a technically relevant substrate. @FootnoteText@@footnote 1@R. Martel, V.Derycke, C. Lavoie, J. Appenzeller, K. K. Chen, J. Tersoff and Ph. Avouris, Phys. Rev. Lett. 87, 256805, 2001. @footnote 2@E. Zahidi, H. Oudghiri Hassani and P. H. McBreen, Nature, 409,1023,2001.