Birth and morphological evolution of step bunches under electromigration.
We analyze the dynamics of electromigration-induced step bunching in the absence of desorption. We show that, even when the instability occurs at long wavelength, hinting to a smooth morphology, the surface suddenly splits into bunches escorted with wide terraces, in agreement with several observations. As the size of the bunches increases, a nonstandard regime is exhibited, namely, the bunches do not match tangentially to the facet, as would the classical Pokrosvky-Talapov shape dictate. This Letter presents a complete scenario of evolution of bunches from their birth up to their ultimate stage.
Chang
J
J
Spectro, UJF-Grenoble 1, Saint Martin d'Hères, France.
Pierre-Louis
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O
Misbah
C
C