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Morphological regions and oblique incidence dot formation in a model of surface sputtering

Emmanuel O. Yewande·Reiner Kree·Alexander K. Hartmann
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Abstract

We study solid surface morphology created by off-normal ion-beam sputtering with an atomistic, solid-on-solid model of sputter erosion. With respect to an earlier version of the model, we extend this model with the inclusion of lateral erosion. Using the 2-dimensional structure factor, we found an upper bound $μ\simeq 2$, in the lateral straggle $μ$, for clear ripple formation. Above this upper bound, for longitudinal straggle $σ\gtrsim 1.7$, we found the possibility of dot formation (without sample rotation). Moreover, a temporal crossover from a hole topography to ripple topography with the same value of collision cascade parameters was found. Finally, a scaling analysis of the roughness, using the consecutive gradient approach, yields the growth exponents $β=0.33$ and 0.67 for two different topographic regimes.

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Emmanuel O. Yewande, Reiner Kree, Alexander K. Hartmann. 2005-12-22. Morphological regions and oblique incidence dot formation in a model of surface sputtering. https://doi.org/10.1103/physrevb.73.115434

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