Author:
Terebinska M. I., ,Tkachuk O. I.,Datsyuk A. M.,Filonenko O. V.,Lobanov V. V., , , ,
Abstract
By the method of density functional theory (B3LYP, 6-31G **) three types of displacements are calculated, namely oscillations as a whole, rotation and diffusion of dimers > Ge = Ge <, > Ge = Si < and > Si = Si <, which are formed on the crystalline surface of Si (001) (4×2) during the deposition of germanium atoms under conditions of molecular beam epitaxy. Calculations of angles of buckling of addimers are carried out. It is shown that when the addimers as a whole oscillate around the equilibrium position, the energy barriers are quite low, the highest of them occurs for a mixed addimer > Si = Ge <. Pure adders > Ge = Ge < and > Si = Si < oscillate between two degenerate states with an energy barrier of 0.042 and 0.014 eV, respectively. The structures of the transition state and the intermediate when the addimer > Ge = Ge < is moved between adjacent cells in the approximation of the constant bond length > Ge = Ge < are obtained. As calculations have shown, all transformations of surface dimers occur with relatively small activation energies, the numerical values of which agree satisfactorily with the results of STM experiments available in the literature.
Publisher
National Academy of Sciences of Ukraine (Co. LTD Ukrinformnauka) (Publications)
Reference9 articles.
1. 1. Tkachuk O.I., Terebinska M.I., Lobanov V.V. 3d core-level binding-energy shifts of Ge adatoms penetrating through Si(001) surface: a DFT study. In: 16th International conference on density functional theory and its applications (Debrecen, Hungary, 2015.) P. 138.
2. 2. Tkachuk O.I. Dependence of the position of the 3d energy levels of Ge atoms on their localization in the surface layer of the crystalline substrate Si (001). In: XXVII International Scientific Conference "Disperse Systems" (Odessa, September 19 - 23, - 2016.) P. 199. [in Ukrainian]
3. 3. Shklyaev A.A. , Ichikava M. Creation of nanostructures of germanium and silicon using a scanning tunneling microscope probe. Uspekhi fiz. Sciences. 2006. 176(9). 913. [in Russian]
4. 4. Tkachuk O.I., Terebinskaya M.I., Lobanov V.V. The structure and properties of primary surface formations of germanium on the Si (001) face: quantum chemical studies. Chemistry, physics and technology of surface. 2014. 5(3). 256.
5. 5. Afanasieva T. V., Greenchuck A. A., Koval I., P and Nakhodkin M. G. Structure of Pure Si-Si, Ge-Ge, and Mixed Si-Ge Addimers on Si(001) Surface. Ukr. J. Phys. 2011. 56. 240.