State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China.
Nano Lett. 2011 Sep 14;11(9):3941-5. doi: 10.1021/nl202190n. Epub 2011 Aug 19.
InAs quantum dots (QDs) are grown epitaxially on Au-catalyst-grown GaAs nanowires (NWs) by metal organic chemical vapor deposition (MOCVD). These QDs are about 10-30 nm in diameter and several nanometers high, formed on the {112} side facets of the GaAs NWs. The QDs are very dense at the base of the NW and gradually sparser toward the top until disappearing at a distance of about 2 μm from the base. It can be concluded that these QDs are formed by adatom diffusion from the substrate as well as the sidewalls of the NWs. The critical diameter of the GaAs NW that is enough to form InAs QDs is between 120 and 160 nm according to incomplete statistics. We also find that these QDs exhibit zinc blende (ZB) structure that is consistent with that of the GaAs NW and their edges are faceted along particular surfaces. This hybrid structure may pave the way for the development of future nanowire-based optoelectronic devices.
在砷化镓纳米线（NWs）上通过金属有机化学气相沉积（MOCVD）外延生长砷化铟量子点（QDs）。这些 QDs 的直径约为 10-30nm，高几纳米，形成在 GaAs NW 的 {112} 侧棱上。在 NW 的底部，QDs 非常密集，而在靠近 NW 底部 2μm 处，QDs 逐渐变得稀疏，直至消失。可以得出结论，这些 QDs 是通过衬底以及 NW 侧壁上的原子扩散形成的。根据不完全统计，足以形成 InAs QDs 的 GaAs NW 的临界直径在 120nm 到 160nm 之间。我们还发现，这些 QDs 表现出闪锌矿（ZB）结构，与 GaAs NW 的结构一致，其边缘沿特定表面成面状。这种混合结构可能为未来基于纳米线的光电器件的发展铺平道路。
