Surface stress-induced island shape transition in Si„001... homoepitaxy
نویسندگان
چکیده
A low-energy electron microscopy study of two-dimensional Si~001! island shapes near thermal equilibrium on 10315 mm large single-domain terraces reveals a continuous increase of island aspect ratio and a shape transition from elliptical to ‘‘American-football’’-like with increasing island size. The size-dependent island shapes are driven by elastic relaxation caused by the intrinsic surface stress anisotropy present on Si~001!. Analysis of the measured elliptical island shapes based on an elastic-model calculation allows a quantitative determination of step energies and of the surface stress anisotropy as a function of temperature.
منابع مشابه
Equilibrium shape of two-dimensional islands under stress
We show that the equilibrium shape anisotropy of two-dimensional islands in heteroepitaxial growth depends on island size, a consequence of the presence of strain. Even in homoepitaxy, in which the island shape has conventionally been equated with the ratio of step energies, a substrate surface stress anisotropy can influence island shape.
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