https://doi.org/10.1007/s100510050264
Noise-assisted mound coarsening in epitaxial growth
1
The Blackett Laboratory, Imperial College,
London SW7 2BZ, UK
2
Department of Physics and Center for Nonlinear Studies,
Hong Kong Baptist University, Kowloon Tong, Hong Kong
3
Institute of Physics, Cukrovarnická 10, 162 00 Praha 6,
Czech Republic
Corresponding author: a lhtang@hkbu.edu.hk
Received:
11
November
1997
Accepted:
28
November
1997
Published online: 15 April 1998
Two types of mechanisms are proposed for mound coarsening during unstable
epitaxial growth: stochastic, due to deposition noise, and deterministic,
due to mass currents driven by surface energy differences. Both yield the
relation between the typical mound height W,
mound size L, and the film thickness H.
An analysis of simulations and experimental data shows that
the parameter R saturates to a value which discriminates sharply
between stochastic (
) and deterministic
(
) coarsening.
We derive a scaling relation between the coarsening
exponent 1/z and the mound-height exponent β which, for a saturated
mound slope, yields
.
PACS: 68.55.-a – Thin film structure morphology / 05.70.Ln – Nonequilibrium thermodynamics, irreversible processes / 81.10.Aj – Theory and models of crystal growth; physics of crystal growth, crytal morphology and orientation
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998