Relationship Between Macrostep Height and Surface Velocity for a Reaction-Limited Crystal Growth Process

Noriko Akutsu

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arXiv · 1903.09929

Relationship Between Macrostep Height and Surface Velocity for a Reaction-Limited Crystal Growth Process

Noriko Akutsu

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Abstract

This work examined the effect of macrostep height on the growth velocity of a vicinal surface during reaction- (interface-) limited crystal growth under non-equilibrium steady state conditions. The Monte Carlo method was employed, based on a restricted solid-on-solid (RSOS) model with point-contact-type step-step attraction (termed the p-RSOS model). Although this is a simple lattice model, the model surface shows a variety of distinctive configurations depending on the temperature and the driving force for crystal growth. The results demonstrate that the surface velocity decreases as the height of the faceted macrostep increases. In addition, the significant variation in surface velocity recently reported by Onuma {\it et al.} in a study based on 4H-SiC was reproduced. This work also shows that the terrace slope, elementary step velocity and elementary step kinetic coefficient are all affected by the faceted macrostep height.

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Noriko Akutsu. 2019-03-24. Relationship Between Macrostep Height and Surface Velocity for a Reaction-Limited Crystal Growth Process. https://arxiv.org/abs/1903.09929

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