Kinetically suppressed ostwald ripening of Ge/Si(100) hut clusters.

Phys Rev Lett

Science and Engineering of Materials, Arizona State University, Tempe, Arizona 85287, USA.

Published: November 2008

Low area density Ge/Si(100) hut cluster ensembles are stable during days-long growth temperature anneals. Real-time scanning tunneling microscopy shows that all islands grow slowly at a decreasing rate throughout the anneal. Island growth depletes the Ge supersaturation that, in turn, reduces the island growth rate. A mean-field facet nucleation and growth model quantitatively predicts the observed growth rate. It shows that Ostwald ripening is kinetically suppressed for Ge supersaturations high enough to support a critical nucleus size less than the smallest facet.

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http://dx.doi.org/10.1103/PhysRevLett.101.216104DOI Listing

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