Modelo DFT de la interacción de monocapas metálicas en semiconductores: AgGe (111) y PbSi (111)

Abstract

Abstract: The surface energy of the different systems; semiconductors (Ge and Si), metals (Ag and Ge), and the metallic overlayers in the semiconductors (Ag/Ge and Pb/Si), has been calculated using density functional theory (DFT) to study the effect of the metal on the properties of the semiconductor. The Pb(111) and Ag(111) adlayers on the Si(111) and Ge(111) surfaces were modeled using the periodic supercell approximation. Periodic energy calculations for the bulk and surfaces of Ge, Si, Pb and Ag, with 12, 11, 10, 9, 8, 7 and 6 layers and SC12-nMn (where SC is Ge or Si; M is Ag and Pb, respectively, and n is the number of layers), the slab models of the metal adlayer system in semiconductors were calculated using the Perdew Wang functional (PW91) with the projector augmented wave (PAW) method within the GGA approximation . According to the results obtained, the metallic adlayers in the semiconductors modify the surface energy of the semiconductors and vice versa. The values ​​for the SC12-nMn system present a similar trend to the metallic layers. The surface energy values ​​are intermediate between the corresponding semiconductor and the metal. These results indicate that if the number of metal layers in semiconductors can be controlled, then the surface energy can be directed.