AVS 51st International Symposium
    Surface Science Monday Sessions
       Session SS2-MoM

Paper SS2-MoM9
Self Assembly on Si(114)-(2x1): Molecular Attachment Via Alkene Functional Groups

Monday, November 15, 2004, 11:00 am, Room 210C

Session: Functionalization of Semiconductor Surfaces
Presenter: D.E. Barlow, Naval Research Laboratory
Authors: D.E. Barlow, Naval Research Laboratory
A.R. Laracuente, Naval Research Laboratory
L.A. Baker, Naval Research Laboratory
L.J. Whitman, Naval Research Laboratory
J.N. Russell, Jr., Naval Research Laboratory
Correspondent: Click to Email
Si(114)-(2x1) is a stable high-index surface oriented 19.5@degree@ between (001) and (111). Because the equilibrium surface reconstruction consists of a single domain of oriented, periodic rows of dimers, rebonded (001) steps, and non-rebonded steps, it is an ideal substrate for examining whether structure-specific reactivity can be used to create organic 1-D nanostructures on Si. We used STM and FTIR spectroscopy to study ethylene and cyclopentene chemisorption on Si(114)-(2x1) in ultra-high vacuum and to characterize the resulting degree of order at the organic-Si interface. Specifically, we examined the orientation, structure, and bonding arrangements of the adsorbates at the various sites on the Si(114) surface. STM and LEED show that well-ordered monolayers can be formed even on this heterogeneous surface. STM images show that the initial adsorption occurs preferentially along a single structural row, rather than by random occupation of multiple binding sites. Polarized transmission FTIR results are consistent with chemisorption of both ethylene and cyclopentene on Si(114)-(2x1) via [2+2] cycloaddition with preferential adsorbate orientation along the rows on the surface. The results clearly demonstrate that Si(114)-(2x1) is a suitable high index surface for organic self assembly using alkene cycloaddition chemistry.