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Noise-assisted Mound Coarsening in Epitaxial Growth

L. -H. Tang·P. Smilauer·D. D. Vvedensky
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Abstract

We propose deposition noise to be an important factor in unstable epitaxial growth of thin films. Our analysis yields a geometrical relation H=(RWL)^2 between the typical mound height W, mound size L, and the film thickness H. Simulations of realistic systems show that the parameter R is a characteristic of the growth conditions, and generally lies in the range 0.2-0.7. The constancy of R in late-stage coarsening yields a scaling relation between the coarsening exponent 1/z and the mound height exponent βwhich, in the case of saturated mound slope, gives β= 1/z = 1/4.

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L. -H. Tang, P. Smilauer, D. D. Vvedensky. 1997-03-06. Noise-assisted Mound Coarsening in Epitaxial Growth. https://doi.org/10.1007/s100510050264

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