Wen C-Y, Reuter M C, Bruley J, Tersoff J, Kodambaka S, Stach E A, Ross F M
School of Materials Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907, USA.
Science. 2009 Nov 27;326(5957):1247-50. doi: 10.1126/science.1178606.
We have formed compositionally abrupt interfaces in silicon-germanium (Si-Ge) and Si-SiGe heterostructure nanowires by using solid aluminum-gold alloy catalyst particles rather than the conventional liquid semiconductor-metal eutectic droplets. We demonstrated single interfaces that are defect-free and close to atomically abrupt, as well as quantum dots (i.e., Ge layers tens of atomic planes thick) embedded within Si wires. Real-time imaging of growth kinetics reveals that a low solubility of Si and Ge in the solid particle accounts for the interfacial abruptness. Solid catalysts that can form functional group IV nanowire-based structures may yield an extended range of electronic applications.
我们通过使用固态铝金合金催化剂颗粒而非传统的液态半导体 - 金属共晶液滴，在硅锗（Si - Ge）和硅 - 硅锗异质结构纳米线中形成了成分突变界面。我们展示了无缺陷且接近原子级突变的单一界面，以及嵌入硅线中的量子点（即几十原子平面厚的锗层）。生长动力学的实时成像表明，硅和锗在固体颗粒中的低溶解度是界面突变的原因。能够形成基于第IV族纳米线功能结构的固体催化剂可能会带来更广泛的电子应用。
