By using scanning tunneling microscopy we found that Ni-containing islands grown on an Ag/Ge(111)-√3 × √3 surface adopt hexagonal (isotropic) shapes when the size is smaller than the critical value ~12.7 nm. Above this critical size islands either grow with no change in shape or become elongated (anisotropic). The shape transformation in the latter case indicates that even on an isotropic surface the influence of surface stress anisotropy on the island growth is significant. Besides, we compared the thermo-evolutions of the Ni-containing islands grown on the multiphase Ag/Ge(111) and the single Ag/Ge(111)-√3 × √3 surfaces and found that the formation of hexagonal and elongated islands is a common feature. This observation made us conclude that the surface stress anisotropy also exerts an impact on the island shape on an inhomogeneous surface.

通过使用扫描隧道显微镜，我们发现当尺寸小于临界值〜12.7 nm时，生长在Ag / Ge（111）-√3×√3表面上的含Ni岛呈六边形（各向同性）形状。超过此临界大小，岛要么生长而没有形状变化，要么变长（各向异性）。在后一种情况下的形状变换表明，即使在各向同性的表面上，表面应力各向异性对岛状生长的影响也是显着的。此外，我们比较了在多相Ag / Ge（111）和单个Ag / Ge（111）-√3×√3表面上生长的含Ni岛的热演化，发现形成了六角形和细长的岛是一个共同的特征。该观察结果使我们得出结论，表面应力各向异性也影响非均匀表面上的岛形。