First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

A. van de Walle; M. Asta; P. W. Voorhees

doi:10.1103/physrevb.67.041308

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First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces

A. van de Walle·M. Asta·P. W. Voorhees

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Abstract

First-principles calculations are used to calculate the strain dependencies of the binding and diffusion-activation 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 eV and 0.12 eV per percent compressive strain. For a growth temperature of 600 degrees C, these strain-dependencies give rise to a 16-fold increase in adatom density and a 5-fold decrease in adatom diffusivity in the region of compressive strain surrounding a Ge island with a characteristic size of 10 nm.

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A. van de Walle, M. Asta, P. W. Voorhees. 2003-01-13. First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces. https://doi.org/10.1103/physrevb.67.041308

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