Abstract
Studies of adsorption of organic molecules on metal-induced super-reconstructed silicon surfaces are important for future Si-based organic electronic device. We investigated the adsorption dynamics of L-tyrosine on Si-Au surface by in situ reflection high-energy electron diffraction. Si(111)5×2-Au and Si(111) √3×√3-Au coexisting surface was exposed to L-tyrosine and the intensities of diffraction spots from corresponding domains were monitored. L-tyrosine was found to adsorb onto the Si(111)5×2-Au domains preferentially, while the Si(111) √3×√3-Au domains were found to be less active. Adsorption sites were revealed by using scanning tunneling microscopy. The molecular adsorption site on the √3×√3-Au was found to be on domain boundary suggesting that the adsorption probability is small on this domain. On the other hand, the adsorbates ordering in 2.3 unit cell distance along [-110] rows were found to create the similar structure as the Si(111)5×2-Au surface. These results suggest that the Si(111)5×2-Au superstructure can be used for the control of the molecular adsorption geometry and ordering effectively. [DOI: 10.1380/ejssnt.2010.303]
