| AVS 54th International Symposium | |
| Surface Science | Monday Sessions |
| Session SS2-MoM |
| Session: | Surface Structure, Growth, and Etching of Silicon and Germanium |
| Presenter: | H. Li, Chonbuk National University, Korea |
| Authors: | H. Li, Chonbuk National University, Korea H. Kim, Chonbuk National University, Korea J.M. Seo, Chonbuk National University, Korea |
| Correspondent: | Click to Email |
Initial stages of antimony (Sb) adsorption on the Si(5 5 12)-2x1 surface have been studied by STM/STS in order to understand interfacial reaction between adsorbed Sb atoms and the Si template with one-dimensional (1-D) symmetry. It has been found that there are two distinct steps, Sb indiffusion and preferential adsorption, at the initial Sb adsorption on Si(5 5 12)-2x1 held at 600 C. Initially, deposited Sb atoms (up to 0.15 ML) diffuse into the subsurface and cause indirect Si deposition. As a result a π-bonded Si chain is firstly formed on dimer/adatom row like homoepitaxy, and the surface reconstruction gradually changes from a (5 5 12) terrace to (337) terraces with (113) steps. The band is flattened by 0.2 eV by subsurface doping with indiffused Sb atoms. As soon as the subsurface Sb sites are saturated by indiffused Sb atoms, additionally deposited Sb atoms are preferentially adsorbed along the upper (113)-step edges and form 1-D Sb wires with a spacing of about 10 nm which corresponds to two periodic lengths of the original (5 5 12) surface. Once Sb-adsorption sites, (113) steps, are saturated, deposited Sb atoms cluster for themselves and do not contribute to nanowire fabrication. From the present studies, it has been found that both Sb indiffusion and preferential adsorption stabilize the high-index surface through relieving surface strain by way of either inserting or attaching Sb atoms, but once such surface strain is relieved, the 1-D growth mode also terminates.