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SECCIÓN A: CIENCIAS EXACTAS

Vol. 4 Núm. 1 (2012)

Estudio DFT del efecto en la energía superficial de sobrecapas metálicas en semiconductores

DOI
https://doi.org/10.18272/aci.v4i1.76
Enviado
agosto 12, 2015

Resumen

Se calculó teóricamente la energía superficial de Ag, Pb, Ge y Si de los sistemas formados por capas metálicas (Ag y Pb) en los semiconductores (Ge y Si), respectivamente para formar los sistemas Ag/Ge y Pb/Si. Para ello, se utilizó el funcional Perdew Wang (PW91) dentro de una aproximación DFT. Para modelar el bulk y las superficies (111) de Ag, Pb, Ge y Si se utilizó el modelo periódico de slab. Los modelos de los semiconductores se construyeron con 12, 11, 10, 9, 8, 7 y 6 capas, los de metales con 1, 2, 3, 4, 5 y 6 capas y para estudiar las monocapas metálicas en los semiconductores se empleó un modelo de 12 capas en total: SC12-nMn (donde SC es Ge o Si; M es Ag y Pb, respectivamente y n es el número de capas). Conforme a los resultados obtenidos, se concluyó que el metal modifica la energía superficial de los semiconductores, y éstos a su vez modifican la energía superficial del metal. Los valores de los sistemas SC12-nMn oscilan en forma similar a la de los semiconductores, aunque con valores intermedios entre el metal y el semiconductor. Estos resultados indican que si el número de monocapas metálicas en un semiconductor se puede controlar, también se puede controlar la energía de superficie del sistema.

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