Department of Materials Science and Engineering, National Taiwan University , Taipei 10617, Taiwan.
Nano Lett. 2015 Mar 11;15(3):1654-9. doi: 10.1021/nl504241g. Epub 2015 Feb 12.
The formation of abrupt Si/Ge heterointerfaces in nanowires presents useful possibilities for bandgap engineering. We grow Si nanowires containing thick Ge layers and sub-1 nm thick Ge "quantum wells" and measure the interfacial strain fields using geometric phase analysis. Narrow Ge layers show radial compressive strains of several percent, while stress at the Si/Ge interface causes lattice rotation. High strains can be achieved in these heterostructures, but we show that they are unstable to interdiffusion.
纳米线中突然出现的 Si/Ge 异质界面为能带工程提供了有用的可能性。我们生长出含有厚 Ge 层和亚 1nm 厚 Ge“量子阱”的 Si 纳米线，并使用几何相分析测量界面应变场。窄 Ge 层显示出数%的径向压缩应变，而 Si/Ge 界面处的应力导致晶格旋转。在这些异质结构中可以实现高应变，但我们表明它们对于互扩散是不稳定的。
