First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge„001... surfaces
نویسندگان
چکیده
First-principles calculations are used to calculate the strain dependencies of the binding and diffusionactivation energies for Ge adatoms on both Si~001! and Ge~001! surfaces. Our calculations reveal that the binding and activation energies on a strained Ge~001! surface increase and decrease, respectively, by 0.21 and 0.12 eV per percent compressive strain. For a growth temperature of 600 °C, these strain-dependencies give rise to a 16-fold increase in adatom density and a fivefold decrease in adatom diffusivity in the region of compressive strain surrounding a Ge island with a characteristic size of 10 nm.
منابع مشابه
First - principles study of adsorption and diffusion on Ge / Si ( 001 ) - ( 2 · 8 ) and Ge / Si ( 105 ) - ( 1 · 2 ) surfaces
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