STM studies of adsorbates on SI(111)-7x7

Abstract

In this project, Scanning Tunneling Microscopy (STM) was employed to perform atomic-resolved surface studies of adsorbates on a Si(111)-7x7 surface, including: (1) Organic molecules (allyl cyanide). The STM images demonstrate that allyl cyanide bind to the surface by interacting with two adatoms-rest atom pairs and prefer to adsorb with two center-center adatoms. Some molecules may adsorb via vinyl group alone. (2) Metal and semiconductor atoms (Ge and Cu). The ordered nanostruture of Ge and Cu clusters were observed. Semiconducting behavior of Ge clusters and 6-Cu atoms structural model on the surface were discussed. (3) Coadsorption of organic molecules and metal (Cu adsorption on thiophene-saturated Si(111)-7x7 surface. STM data indicate that the reaction of Cu with the thiophene-saturated Si(111)-7x7 surface leads to the formation of S-Cu dative bond. This observation allows us to realize the possible further functionalization of the silicon surface.