Rastelli A, Kummer M, von Känel H
INFM-Università di Pavia, Via Bassi 6, I-27100 Pavia, Italy.
Phys Rev Lett. 2001 Dec 17;87(25):256101. doi: 10.1103/PhysRevLett.87.256101. Epub 2001 Nov 28.
The evolution of strained Ge/Si(001) islands during exposure to a Si flux was investigated by scanning tunneling microscopy. Dome islands display appreciable shape changes at Si coverages as low as 0.5 monolayer. With increasing coverage, they transform into [105]-faceted pyramids, and eventually into stepped mounds with steps parallel to the <110> directions. These morphological changes are induced by alloying and represent a complete reversal of those previously observed during Ge island growth. The results are interpreted with a simple model in which the equilibrium shape of an island mainly depends on its volume and composition.
通过扫描隧道显微镜研究了应变锗/硅（001）岛在暴露于硅通量过程中的演变。穹顶状岛在硅覆盖量低至0.5单层时就显示出明显的形状变化。随着覆盖量增加，它们转变为[105]面的棱锥体，最终转变为台阶平行于<110>方向的阶梯状丘。这些形态变化是由合金化引起的，并且代表了先前在锗岛生长过程中观察到的那些变化的完全逆转。用一个简单的模型对结果进行了解释，在该模型中，岛的平衡形状主要取决于其体积和组成。
